assessing the impact of urban expansion...
TRANSCRIPT
ASSESSING THE IMPACT OF URBAN EXPANSION ON
LAND SURFACE TEMPERATURE IN LAHORE USING
REMOTE SENSING TECHNIQUES
By
Muhammad Nasar u Minallah
Thesis Submitted in Partial Fulfillment of
The Requirements for the Degree of
DOCTOR OF PHILOSOPHY
IN
GEOGRAPHY
DEPARTMENT OF GEOGRAPHY
UNIVERSITY OF THE PUNJAB
LAHORE
II
ABSTRACT
Lahore, a metropolis of Pakistan, has been experiencing rapid urban growth over
the past few decades. The growth of urban population and socio-economic development
has resulted in the rapid increase of urban expansion. A major impact of this urban
expansion is being observed in the form of an increase in land surface temperature which
can be determined by using thermal infrared band of Landsat images. In order to
comprehend urban climate, LST is essential to be observed. The present research is an
effort to evaluate urban expansion and its impact on Land Surface Temperature (LST) of
Lahore, Pakistan through remote sensing technique. It reveals LST’s spatial patterns,
explores its relationship with the dynamics of urban expansion relative to the land use
change. Two sets of temperature data are used in this research: satellite image data
utilizing six dates of Landsat 5/TM, 7/ETM+ and 8/OLI_TIRs imagery obtained in 1973,
1980, 1990, 2000, 2010 and 2015, respectively and the ground weather station
atmospheric temperature data, over a long period (1950 to 2015) for the urban and the
nearby rural stations. The observations gathered from the weather stations indicate a
significant climatic change in terms of urban climate of the city through the time series
when compared with the spatial trends of the urban and the rural station (mainly for mean
minimum temperature). The satellite images are also utilized to develop a map of NDBI,
NDVI and LSE of Lahore, which in turn is utilized to estimate the land surface
temperature variations of Lahore. The relationship between NDVI and LST denotes high
negative correlation which reflects that the vegetation cover can significantly reduce the
influence of urban heat island, whereas the relationship between NDBI and LST indicates
high positive correlation suggesting that the urban built-up area strengthens the heat
influence on UHI. The massive scale of hot spots is observed over the densely populated,
and industrial areas where the urban heat islands are likely to develop, whereas the much
colder areas are observed over vegetation and water bodies. The integration of GIS and
satellite remote sensing techniques has proved to be efficient and effective for evaluating
and monitoring urban expansion and making assessments of its impact on land surface
temperature of Lahore.
III
ACKNOWLEDGMENT
I have the pearl of my eyes to admire blessings of the Compassionate and Omnipotent
because the words are less, knowledge is limited and time is short to express His Dignity It is one
of the infinite blessings of Allah that He bestowed me with potential and ability to
complete the present research. I offer my humblest gratitude from the hearts of my heart
to the Holy Prophet Hazrat Muhammad (Peace be upon Him), who is always a paragon
of guidance and knowledge, for humanity.
Foremost, I would like to extend my deepest sense of gratitude to my kind
supervisor Prof. Dr. Abdul Ghaffar, Chairman Department of Geography, University of
the Punjab, Lahore, Pakistan. My Research work is indebted to him for his enthusiastic
guidance, considerate attitude, ever-pouring inspiration and ushering supervision. I offer
full fathom feeling of sheer admiration to my honoured guide for his thankless help, wise
suggestions, patience, motivation, enthusiasm, and immense experience. His unceasing
guidance facilitated me throughout the research and compilation of this thesis. I could
not have imagined having a better advisor and mentor for my PhD study.
I would like to expresses my orisons and indebtedness to my affectionate parents,
who made my studies their prior interest. I am tongue-tied to express my love and
gratitude for my parents, whose prayers still prompt me to attain my objectives. I find it
hard to transcribe my gratitude and profound admiration to my mother (Sajjad Akhtar
Bhalli), I have always been stimulated and encouraged to move forward in delivering my
best by my affectionate father Dr. Muhammad Nawaz Sajjad Bhalli (Late). It is
being without him that I'll never get used to. “Long, long shall I rue thee.” I owe my
gratitude to my dearest sisters, and brothers, especially Dr. Muhammad Waseem Nawaz
Bhalli and Dr. Muhammad Zain-ul-Abbeedin Bhalli for their spiritual and intellectual
inspiration and support to carry out my nobler ideals of life. I can do no more than
reaffirm my timeless devotion to all members of my family.
Muhammad Nasar-u-Minallah
IV
DEDICATED
TO
My Affable Father
Dr. Muhammad Nawaz Sajjad Bhalli (Late)
A symbol of success for me!
Who always behaved like a friend
Whose love, valuable guidance and
Financial assistance enabled me to perceive and pursue higher goals in life
&
My Adorable Mother
The Embodiment of love and Kindness
Who enlightened my spirit of learning
In her lap
V
DECLARATION
The work reported in this thesis was carried out by me under the supervision of
Prof. Dr. Abdul Ghaffar, Chairman, Department of Geography, University of the Punjab,
Lahore, Pakistan.
I hereby declare that the title of thesis is “Assessing the Impact of Urban
Expansion on Land Surface Temperature in Lahore Using Remote Sensing
Techniques” and the contents of thesis are the product of my own research and no part
has been copied from any published source (except the references, standard mathematical
or genetic models /equations /formulas /protocols etc.). I further declare that this work has
not been submitted for award of any other degree/diploma. The University may take
action if the information provided is found inaccurate at any stage.
Signature of the Scholar
Muhammad Nasar u Minallah Registration No. : 2012-GEO-17
VI
LIST OF ABBREVIATIONS
ACGR………………………………………………….…Annual Compound Growth Rate
AOI…………………………………………………….…………………...Area of Interest
ASTER .................Advanced Space borne Thermal Emissions and Reflection Radiometer
ATLAS…………………………………...Advance Thermal and Land Application Sensor
AVHRR ..........................................................Advanced Very high Resolution Radiometer
CA…………………………….…………………………………………Cellular Automata
CBD………………………………………………………………Central Business District
CDGL…………………………………………………………...City District Govt. Lahore
CIR .................................................................................................................Color Infrared
DCR………………………………………………………………...District Census Report
DEM ...............................................................................................Digital Elevation Model
DN………………………………………………………………………….Digital Number
EPA ................................................…………………….Environmental Protection Agency
ESP…………………………………………………………..Economic Survey of Pakistan
ESRI…………………………………………...Environmental Systems Research Institute
ET………………………………………………………………………..Evpotranspiration
ETM+……………………………………………………..Enhance Thematic Mapper Plus
GCPs………………………………………………………………..Ground Control Points
GIS .......................................................................………..Geographic Information System
GLCF…………………………………………………………..Global Land Cover Facility
GOP………………………………………………………………………Govt. of Pakistan
GPS .............................................................................................Global Positioning System
IBI……………………………………………………………...Index based Built-up Index
IPCC…………………………………….…...Intergovernmental Panel on Climate Change
VII
ISA ...............................................................................................Impervious Surface Area
JICA……………………………..……………….Japan International Cooperation Agency
KIA…………………………………………………………….Kappa Index of Agreement
LANDSAT ....................................................……………...Land Remote Sensing Satellite
LDA……………………………………………………….Lahore Development Authority
LDCs…………………………………………………………...Least Developed Countries
LST ....................................................................……………….Land Surface Temperature
LULC .................................................................................................Land Use Land Cover
LULCC..................................................................................Land Use Land Cover Change
MAT……………………………………………………………Mean Annual Temperature
MMiT……………………………………………...Mean Monthly Minimum Temperature
MMxT………………………………………...…..Mean Monthly Maximum Temperature
MLA……………………………………………………..Maximum Likelihood Algorithm
MODIS ....................................................Moderate Resolution Imaging Spectroradiometer
MODTRAN .......................................................Moderate Resolution Transmission Model
MSS………………………………………………………………...Multi Spectral Scanner
MUHI .................................................................………………...Micro Urban Heat Island
NASA………………..……………………..National Aeronautics and Space Administration
NESPAK………………………………………….National Engineering Services Pakistan
NDVI ...................................................................Normalized Difference Vegetation Index
NDBI ........................................................................Normalized Difference Built-up Index
NDBeI .....................................................................Normalized Difference Bareness Index
NDSI ............................................................................Normalized Difference Snow Index
NDWI ..........................................................................Normalized Difference Water Index
NIPS……………………………………………......National Institute of Population Study
NIR…………………………………………………………………………...Near Infrared
VIII
NOAA .......................................National Oceanographic and Atmospheric Administration
OBIA………………………………………………………..Object Based Image Analysis
OLI………………………………………………….…………....Operational Land Imager
PCO…………………………………………………………Pakistan Census Organization
PDS………………………………………………………...Punjab Development Statistics
PMD……………………………………………………Pakistan Metrological Department
RBG………………………………………………………………………..Red Green Blue
RS…………………………………………………………………………Remote Sensing
SAARC……………………………….South Asian Association for Regional Corporation
SAVI……………………………………………………….Soil Adjusted vegetation Index
SD……………………………………………………………………….System Dynamics
SHI……………………………………………………………………..Surface Heat Island
SLC…………………………………………………………………….Scan line Corrector
SRS………………………………………………………………Satellite Remote Sensing
SUHI ...........................................................................................Surface Urban Heat Island
SWIR………………………………………………………………….Short Wave Infrared
TIRs………………………………………………………………Thermal Infrared Sensor
TMAs……………………………………………………Town Municipal Administrations
TM ............................................................................................................Thematic Mapper
TOA………………………………………………………………...Top of the Atmosphere
UCL .....................................................................................................Urban Canopy Layer
UES……………………………………………………………..Urban Expansion Scenario
UHI ...........................................................................................................Urban Heat Island
UHS……………………………………………………………………….Urban Heat Sink
ULU……………………………………………………………………….Urban Land Use
UN…………………………………………………………………………..United Nations
IX
UNFCCC………..……United Nations Framework of the Convention on Climate Change
UNEP……………………………………………United Nations Environment Programme
UNFPA…………………………………………………….United Nation Population Fund
UNO………………………………………………………….United Nations Organization
USCCSP…………………………………………….US Climate Change Science Program
USGS ................................................................................United States Geological Survey
VWI………………………………………………………Vegetation Water Content Index
WGS ................................................................................................World Geodetic System
X
TABLE OF CONTENTS
S. No…………………………………. Contents… …………………………………Page
Title……………………………………………………...…………………………………i
Abstract ……………………………………………………….…………………………..ii
Acknowledgements….........................................................................................................iii
Dedication ……………………………………………………….……………………….iv
Declaration …........................................................................................... ...........................v
List of Abbreviation…........................................................................................................vi
Table of Contents………………………………………………………...………………..x
List of Tables….................................................................................................................xvi
List of Figures…...............................................................................................................xix
CHAPTER 1: INTRODUCTION…………...………………….……...………………01
1.1. Introduction…………………………………………………………..…………..01
1.2. Background of the Study….…………………………………………..……...…..03
1.3. Statement of the Problem…………………….………………………….……….06
1.4. Hypothesis of the Research .…………………………………………..…………10
1.5. Aim of the Study ………………………………………………..…..…...……....10
1.6. Objectives of the Study………………………………..…………………………10
1.7. Research Questions……………………………………….…………………..….11
1.8. Study Area……………...………...………………………………………………11
1.8.1. Physiography………………..………………………………………………..13
1.8.1.1. Topography……………..……………………………………………14
1.8.2. Climatic Conditions…..………..………………………………......................14
XI
1.8.2.1. Temperature…………..………………………………………………14
1.8.2.2. Rainfall…………………………………………………………….....16
1.8.2.3. Humidity………………………………………………………….......16
1.8.2.4. Wind Speed and Direction…………………………………………...17
1.9. Significance of the Study.………………………………………………………..18
1.10. Thesis Organization………………………………………….…………………...20
CHAPTER 2: URBAN EXPANSION AND ITS IMPACT ON LAND SURFACE
TEMEPERATURE: A REVIEW……………………………………………...............23
2.1. Introduction………………………………………………………..……………..23
2.2. Urban Expansion and Land use Changes……………..………………………….24
2.3. Role of Remote Sensing in Assessing Urban Expansion…………….…………..27
2.4. Urban Climate Patterns and Land Surface Temperature……..…………………..31
2.5. Use of Remotely Sensed Data in Land Surface Temperature Estimation………..36
2.6. Relationship between NDVI, NDBI and LST……………………………………41
2.7. Urban Expansion and its Impact on Land Surface Temperature ………………...43
2.8. Urban Heat Island………………………………………………………………...47
CHAPTER 3: MATERIAL AND METHODS……..……………..………………......54
3.1. Introduction ……………………………………………………………..……….54
3.2. Data and its Sources……….……………………………………………...……...54
3.2.1. Primary Data…………………………………..…………………….......55
3.2.1.1. Satellite Images……………………………………………..........55
3.2.2. Secondary Data……………………………………………………...........57
3.2.2.1. In-Situ Atmospheric Temperature Data………….…..…………..58
3.2.2.2. Census Data………………………………..…………..................60
3.2.2.3. Land use Data…………………………………..…….……..........60
XII
3.3. Methodology………………………………………………..……………………61
3.3.1. Image Pre-Processing…………………………..………..……………….63
3.3.1.1. Geometric and Radiometric Correction …..……..………………64
3.3.1.2. Generating Subset Images…..……………………..……………..65
3.3.1.3. Image Enhancement……………………………….……………..66
3.3.1.4. Bands Combination for Visual Interpretation…………..………..66
3.3.2. Image Classification………………………...……………………………68
3.3.2.1. Supervised Classification………………………………………...69
3.3.2.2. Training Stage…………………………………...……………….72
3.3.2.3. Classification Stage………………………...…………………….73
3.3.3. Classification Accuracy Assessment………………………..…...……….74
3.3.4. Post-classification Change Detection………………………...…………..75
3.3.5. Urban Expansion Change Detection ……………………………..……...76
3.3.6. Methods of Retrieving Land Surface Temperature………..…...………...76
3.3.6.1. Brightness Temperature Retrieval………………………...……...78
3.3.6.2. Method of Derivation of NDVI………………..……..…………..80
3.3.6.3. Land Surface Emissivity (LSE)…..………………...…………….81
3.3.6.4. Land Surface Temperature Retrieval………………...…………..81
3.3.6.5. Thermal Map Generation………………………………………...82
3.3.7. Relationship between LST and Land use………………………………...82
3.3.8. Regression Analysis Determining the Relationship between NDVI,
NDBI and LST…………………………………………………………...83
3.3.9. Atmospheric Temperature Trends from 1951 to 2015…………………...85
3.3.10. Software used in Analysis……………………………………………......87
CHAPTER 4: URBAN EXPANSION OF LAHORE, 1951-2015…………................88
XIII
4.1. Introduction……………………………………………………………………....88
4.2. Population Growth of Lahore from 1901 to 2015……………………….....……90
4.2.1. Population Growth of Lahore from 1901-1941………......………………90
4.2.2. Population Growth of Lahore from 1951 to 2015…………...…………...92
4.2.3. Population Growth Rate of Lahore from 1951-2015…………………….94
4.2.4. Population Distribution and Density of Lahore……………..…………...95
4.2.5. Urban and Rural Population of Lahore……………...……….…………102
4.3. Urban Expansion of Lahore from 1951 to 2015……………………...…………105
4.3.1. Historical Expansion of Lahore: Pre-1947………………….…………..106
4.3.2. Urban Expansion of Lahore from 1951 to 1972 ( Pre-Satellite Era)……108
4.3.3. Land use Changes of Lahore from 1972-2015…………………..……...109
4.3.3.1. Nature, Rate and Extent of Land use Change…………...….116
4.3.4. Temporal Urban Expansion of Lahore from 1972-2015…………….….118
4.3.5. Annual Rate of Urban Expansion from 1972 to 2015………...………...121
4.3.6. Urban Expansion Intensity Index…………………………………….…122
4.3.7. Urban Change Detection of Lahore from 1973-2015……………….….123
4.4. Classification Accuracy Assessment……………….………………….………..126
CHAPTER 5: LAND SURFACE TEMPERATURE VARIATIONS….……..……130
5.1. Introduction……………………………………………………………..………130
5.2. Factors Increasing Land Surface Temperature ……………….……..……….....131
5.2.1. Rapid Growth of Population………….……...……………….…………132
5.2.2. Land use Changes………………………………………………….……134
5.2.2.1. Urban Built-up Area………………………………..……….135
5.2.2.2. Reduction in Agricultural Land………………………..…....138
XIV
5.2.3. Increase in Registered Factories...……………...……………………….139
5.2.4. Increase in Registered Vehicles…………….………………….……….141
5.2.5. Increase in Greenhouse Gases…………………………..………..……..143
5.3. Comparison of Contributing Factors of Changing Temperature Trends……....146
5.3.1. Multiple Regression Analysis………………………………………………......147
5.4. Atmospheric Temperature Trends of Lahore from 1950 to 2015……..…..…....148
5.5. Land Surface Temperature Variations of Lahore, 1990-2015………………….150
5.6. Town wise Trends of LST of Lahore Between 1990 and 2015….………..........156
5.7. The Correlation between LST and Urban Land use Patterns………...…………158
5.8. Correlation between LST and Indices………………………………...………...161
5.8.1. Relationship of LST to NDVI………………………………...………...161
5.8.2. Relationship of LST to NDBI………………………………...………...166
5.9. Cross Validation of Satellite and Met Station Data…………………………….171
5.10. Urban Heat Island of Lahore………………………………………...….………172
6. SUMMARY, CONCLUSION AND RECOMMENDATIONS..……………….178
6.1. Summary ………………………………………………………………..……...178
6.2. Conclusion…………………………………………………………...…...……..184
6.3. Recommendations………………………………………………………………189
7. REFERENCES………………………………………………………..…………...192
APPENDICES................................................................................................................232
Appendix 1: Mean Annual Recorded Temperature (°C) 1950-2015...............................232
Appendix 2: Annual Trends of Ambient Air Quality of Lahore …………….….……...233
Appendix 3 Air Quality Parameters vs Population density and Temperature………….234
Appendix 4: Urban Population of Lahore, Punjab, Pakistan …………………………..234
Appendix 5: Number of Registered Vehicles of Lahore………...……………………...235
XV
Appendix 5: Number of Registered Factories in Lahore……………………………….235
Appendix 6: Published Research Paper…………………………………………………236
XVI
LIST OF TABLES
Table Title Page
Table 1.1: Urban Development of Lahore...................................................................08
Table 1.2: Mean Temperature (°C) & Precipitation of Lahore 1950-2015………….15
Table 2.1: Radiative Properties of Several Materials…………………………..........39
Table 2.2: Urban-Rural Contrasts………………………………………………........45
Table 3.1: Metadata of Landsat (5, 7 and 8) Satellite Images……………………….56
Table 3.2: Ground Weather Station of Lahore…………………………………...….59
Table 3.3: Data type used for the Study……………………………………………..61
Table 3.4: Description of Landsat Imagery Spectral Resolution…………………….64
Table 3.5: Band Combinations in RGB Comparisons….............................................67
Table 3.6: Description of the Land use Classification Scheme used in the Study…..71
Table 3.7: The Metadata of Landsat 8-TIR………………………………………….79
Table 3.8: Detail of Calibration Constant………………………………………........80
Table 3.9: Procedure of Applied Statistical Test……………………………….........86
Table 4.1: Population Growth rates and Inter-censual increase of Lahore………….91
Table 4.2: Rank of Lahore among the Major Cities of Pakistan since 1951………...92
Table 4.3: Population Increase in Lahore from 1951-2015….....................................92
Table 4.4: Population Growth Inter-censual increase in Lahore from 1951-2015…..95
Table 4.5: Tehsils of Lahore and Population in 1998………………..........................96
Table 4.6: Population distribution and Density of Lahore from1951-2014…………96
Table 4.7: Town wise Urban & Rural Union Councils of Lahore …………….........98
Table 4.8: Population Densities of Nine Towns of Lahore 1998…………………....99
XVII
Table 4.9: Population Densities of Nine Towns of Lahore (2010 Estimates)….…..100
Table 4.10: Population Densities of Nine Towns of Lahore (2015 Estimates)….......101
Table 4.11: Population of Lahore and its Constituent Administrative Units………..102
Table 4.12: Lahore Urban Population and ACGR 1951-1998 & 2015………….......103
Table 4.13: Urbanization (1951-1998) in Lahore and 2015 Estimated……………...104
Table 4.14: Area Statistics and Percentage of Land use of Lahore from 1973-2015..110
Table 4.15: Overall Amount, rate, nature and Extent of Land use change………….117
Table 4.16: Comparison of Built-up and Non Built-up Area of Lahore...…………..118
Table 4.17: The Urban Area, ARU and Increase urban area of Lahore……..............121
Table 4.18: Indices of urban temporal Expansion of Lahore………………..............122
Table 4.19: Overall classification Accuracy and Kappa (k) Statistics………………128
Table 4.20: User’s and Producer’s Accuracy for each Land use Type……………...128
Table 4.21: Conditional Kappa for each Category…………………………………..128
Table 5.1: Pearson Correlation between Population Growth and MAT……….…...134
Table 5.2: Land use Changes Patterns of Lahore since 1973 to 2015….…………..135
Table 5.3: Pearson Correction between Urban Built-up Area and MAT…………..138
Table 5.4: Pearson Correction between Reduction in Vegetation and MAT………139
Table 5.5: Pearson Correction analysis between MAT and Factories of Lahore…..140
Table 5.6: Person Correction between Registered Vehicles and MAT of Lahore....143
Table 5.7: Degree of Correlation of Different Drivers behind the changing
Temperature Trends…………………………………………………….146
Table 5.8: Multiple Regression Analysis…………………………………………..148
Table 5.9: Descriptive Statistics of Land Surface Temperature of Lahore…...……151
XVIII
Table 5.10: Land Surface Temperature Change from 1990 to 2015……………..….151
Table 5.11: Land Surface Temperature Variations with Different land uses…..........159
Table 5.12: Relationship between Vegetation Density and LST…………………….164
Table 5.13: Relationship between Built-up Area and LST………………………….169
Table 5.14: Cross Validation of LST with Lahore Urban MET Station Data……....171
Table 5.15: Cross Validation of LST with Lahore Rural MET Station Data……….171
Table 5.16: dTmin and dTmax over the period of 65 year at Lahore………………..173
Table 5.17: Regression result of Temperature of Lahore Urban station and Lahore
airport rural Station during 1950 to 2015……………………………….173
XIX
LIST OF FIGURES
Figure Title Page
Figure 1.1: Geographical Location of the Study Area (Lahore)….…………….…….12
Figure 1.2: Administrative Towns and Urban sub region of Lahore………...…….…13
Figure 1.3: Mean Monthly Temperature (oC) of Lahore from 1950 to 2015………...15
Figure 1.4: Mean Annual Atmospheric Temperature of Lahore from 1950 to 2015...16
Figure 1.5: Climograph of Lahore based on 65 years Climatic Data….......................17
Figure 1.6: Thesis Organization Flow Chart………………………………………….21
Figure 2.1: Landsat Mission’s Timeline and Their Current Status…………….……..30
Figure 2.2: The Albedo of different Land Surfaces…………………………..………38
Figure 2.3: Temperature profile of the Urban “Heat Island” shows the increase in
Temperature with increase Urbanization…...............................................48
Figure 2.4: Causes of Increase of Urban Temperature and UHI Formation………….49
Figure 2.5: Effect of Urban Heat Island Formation…………………………………..50
Figure 3.1: Imagery used for Urban Analysis ……….………………………...……..57
Figure 3.2: Meteorological Station in Lahore……………………………….………..59
Figure 3.3: Flow Diagram of Research Methodology………………………..………62
Figure 3.4: Spectrally Enhanced Subset Images showing Study Area…………...…..66
Figure 3.5: Flow Chart of Image Classification Process…..........................................69
Figure 3.6: Basic Steps in Supervised Classification…………………………………70
Figure 3.7: An example of Training Samples on an Image…......................................73
Figure 3.8: Flow Chart of Image Classification Accuracy Assessment Process……..74
Figure 3.9: Process of Land Surface Temperature Retrieval…....................................77
XX
Figure 3.10: Regression Analysis Flow Chart…………………………………………84
Figure 3.11: Random sample points for Relationship between LST and NDVI………84
Figure 4.1: Population Growth of Lahore from 1901 to 1941…..................................91
Figure 4.2: Inter-censual Increase and Growth Rates of Lahore 1911-1941………....91
Figure 4.3: Population Growth of Lahore from 1951 to 2015…..................................93
Figure 4.4: Growth rate and Inter-censual Increase from 1951-1998……………..….95
Figure 4.5: Population Density of Lahore from 1951-2015………………………….97
Figure 4.6: Town wise Population Distribution and Density of Lahore in 1998…….99
Figure 4.7: Town wise Population Distribution and Density of Lahore in 2010……100
Figure 4.8: Town wise Population Distribution and Density of Lahore in 2015……101
Figure 4.9: District, Urban and Rural Population of Lahore...……………………...104
Figure 4.10: Urbanization and Built-up area Tends of Lahore……………………….105
Figure 4.11: Urban Expansion of Lahore From 1850 to 2015.……………………….107
Figure 4.12: Urban Expansion of Lahore from 1947-1972…………………………..109
Figure 4.13: Land use Distribution of Lahore 1973……….…………………...…….111
Figure 4.14: Land use Distribution of Lahore 1980………….………………………112
Figure 4.15: Land use Distribution of Lahore 1990………………………………….113
Figure 4.16: Land use Distribution of Lahore 2000…………………………….........114
Figure 4.17: Land use Distribution of Lahore 2010………………………………….115
Figure 4.18: Land use Distribution of Lahore 2015………………………………….115
Figure 4.19: Nature of Relative Land use Changes of Lahore from 1973 to 2015…...118
Figure 4.20: Land use Comparison of Lahore from 1973 to 2015…………………...118
Figure 4.21: Comparison of Built-up and Non Built-up area of Lahore…………….119
XXI
Figure 4.22: Temporal Change in Urban Expansion of Lahore in 1973 and 2015…...119
Figure 4.23: Temporal Urban Expansion of Lahore from 1973 to 2015………..........120
Figure 4.24: Urban Change Detection of Lahore from 1973 to 2015………………...124
Figure 4.25: Spatial Expansion of Lahore from 1973 to 2015……………………….125
Figure 4.26: An Example for Test sample Taken on an Image……………………....127
Figure 5.1: Factors Increasing Land Surface Temperature………………...………..131
Figure 5.2: Population Growth of Lahore from 1951 to 2015………….…...............133
Figure 5.3: Correlation between Population growth and MAT of Lahore………….133
Figure 5.4: Land use Patterns of Lahore from 1973 to 2015………………………..136
Figure 5.5: Population and Urban Built-up area of Lahore from 1973 to 2015…….137
Figure 5.6: Correlation between Urban Built-up area and MAT of Lahore………...137
Figure 5.7: Correlation between reduction in Agricultural land and MAT of
Lahore…………………………………………………………………...139
Figure 5.8: Number of Registered Factories of Lahore from1990-2015……………140
Figure 5.9: Relationship between MAT and Registered Factories of Lahore...…….140
Figure 5.10: Number of Registered Vehicles of Lahore……………………………...141
Figure 5.11: Trends of Vehicles of Lahore from 1990 to 2015....................................141
Figure 5.12: Relationship between Vehicles and MAT of Lahore...…………………143
Figure 5.13: Greenhouse gases from 2008 to 2010 in Lahore……………………......145
Figure 5.14: Comparison showing all Contributing Factors of Temperature change...147
Figure 5.15: Atmospheric Temperature Variations of Lahore from 1950 to 2015.......149
Figure 5.16: Trend line showing future prediction of MAT of Lahore until 2030…...150
Figure 5.17: Land Surface Temperature Variations of Lahore in 1990………………152
XXII
Figure 5.18: Land Surface Temperature Variations of Lahore in 2000………………153
Figure 5.19: Land Surface Temperature Variations of Lahore in 2010………………154
Figure 5.20: Land Surface Temperature Variations of Lahore in 2015………………155
Figure 5.21: Town Wise Comparison of LST of Lahore in 1990 and 2015………….157
Figure 5.22: Town wise Trends of LST of Lahore in 1990 and 2015..........................158
Figure 5.23: Land Surface Temperature Variations with Different Land uses..……...160
Figure 5.24: Spatial Distribution of LST and NDVI of Lahore in 1990……………...162
Figure 5.25: Spatial Distribution of LST and NDVI of Lahore in 2000……………...163
Figure 5.26: Spatial Distribution of LST and NDVI of Lahore in 2010……………...163
Figure 5.27: Spatial Distribution of LST and NDVI of Lahore in 2015……………...164
Figure 5.28: Relationship between NDVI and LST from 1990 to 2015……………...165
Figure 5.29: Spatial Distribution of LST and NDBI of Lahore in 1990……………...167
Figure 5.30: Spatial Distribution of LST and NDBI of Lahore in 2000……………...167
Figure 5.31: Spatial Distribution of LST and NDBI of Lahore in 2010……………...168
Figure 5.32: Spatial Distribution of LST and NDBI of Lahore in 2015……………...168
Figure 5.33: Relationship between NDBI and LST from 1990 to 2015……………...169
Figure 5.34: Comparison between LST with Lahore Urban-Rural MET Data………171
Figure 5.35: The Mean Maximum & Minimum Temperature Variations of Lahore at
Lahore Airport and Shadman Observatories…………………………...174
Figure 5.36: Urban and Rural Temperature Trends to represent long term UHI…….175
Figure 5.37: Presence of Urban Heat Island in 1990……………………....................176
Figure 5.38: Presence of Urban Heat Island in 2015……………...………………….176
1
CHAPTER 1: INTRODUCTION
1.1. Introduction
Urban expansion is highly important geographical phenomenon in today’s world
(Shekhar, 2007; Yesserie, 2009). Urbanized areas are stated to be the most dynamic
places on the earth surface in the world’s urban growth history (Yuan et al., 2005).
Aristotle asserts that the authority of the city state must be subjected to the human beings
in order to attain good life (Zhang, 2009). It was reported in 2008 that human civilization
achieved significant milestone which had no precedent as the half (3.3 billion people) of
the total population was residing in urban areas (UN, 2008). The world population in
2015 was estimated to be 7.3 billion out of which 4.4 billion (60 per cent) people were
inhabitants of Asia. It is estimated that by the end of 2016, 83 million more people would
become the part of global population (UN, 2015). Presently, the annual growth of the
global population is comparatively slower than the growth observed in the past. Current
annual growth of world population is 1.18 per cent while it was determined 1.24 per cent
almost a decade ago. At the present growth rate, 1.18 per cent, of the world population,
83 million people are added annually. It is projected that the global population in 2030
would be 8.5 billion which means the addition of 1 billion people and it would be 9.7
billion in 2050 and it would reach 11.2 billion by the end of 21st century (UN, 2015). All
over the world, most of the people prefer to live in cities as compared to country side, 54
% of the global population was urbanized in 2014. It is estimated that in 2050, 66% of the
global population is projected to be residing in urban areas. Rapid increasing of
urbanization and population trends project that a population of more 2.5 billion people
would be residing in the cities by 2050, with approximately 90% of increase concentrated
in Africa and Asia (UN, 2014).
The rapid expansion of urban areas is a recurring demographic phenomenon
shared by the developing countries in general (Tewlode, 2011), and Pakistan in particular.
The level of urbanization has increased significantly in developing countries owing to
rapid increase in urban population. In Pakistan, the percentage of people residing in cities
has increased from only 17.8 per cent in 1951 to about 32.5 per cent in 1998 and 39.2
per cent in 2015 (GoP, 2015). Within the Asia-Pacific region, based on both the urban
expansion and urbanization level, Pakistan is one of those countries which are undergoing
2
moderate level of urbanization. If compared with other SAARC countries, Pakistan has
the highest number of inhabitants hailing from urban areas as 39.2 percent of its
population lives in cities. The other countries of south Asia are far behind Pakistan in
terms of urban population and urbanization level. It is estimated that by 2030 about 50%
of Pakistan’s population would settle in cities (GoP, 2015). Pakistan is urbanizing at an
annual rate of 3 per cent, the fastest pace in South Asian countries (Kugelman, 2013).
According to UNFPA (2007), most of the urban areas are situated at the heart of the
fertile agricultural lands and the trends of the urban expansion focus on fringe areas.
Agarwal et al., (2002), reports that 6.8 million km2 of forests, grasslands and woodlands
have been transformed into urban land uses in the last three centuries on a global basis.
These land use changes have significant effects on the earth’s surface resources and
climate of the urban areas (Araya, 2009).
Atmospheric and land surface alterations due to urban land expansion change
thermal physical properties of urban areas that become warmer than their adjacent rural
areas (Van and Bao, 2010). The distinguished climatic condition termed ‘Urban Heat
Island’ (Brandsma et al., 2012; Kantzioura et al., 2012) is rapidly developing in
urbanized areas throughout the world (Kumar et al,. 2012). Land use changes due to
urban expansion always play a vital role in regional and local climatic conditions of the
monsoon countries (Coltri et al., 2009). One of the most important effects of land use
change is observed in the form of variation of land surface temperature in urban areas.
The major aspect of urban heat island phenomenon is its effects on the local climate and
resultant inconsistency in temperature in cities. Anthropogenic activities in urban areas
cause emission of the greenhouse gases which further intensify the urban heat and
contribute to enhance the spatial extent of urban heat island in metropolitan cities. The
observations of atmospheric processes in the urban areas are essential for the
comprehension of climatic changes, specifically at the local and regional level. The study
of land surface temperature variation is essential for the assessment of urban micro-
climate.
The Land Surface Temperature (LST) has become more and more significant
during the last five decades due to urban growth and increased consumption of energy in
cities of the world (EPA, 2008). As major human activities are concentrated in urban
areas, about 70 per cent of world energy is consumed in cities. The major anthropogenic
3
influences on urban climate are land use changes, such as development, industrial
activities and the emission of greenhouse gases. Land use changes (Agarwal et al., 2002;
Pielke et al., 2002) and increase in greenhouse gases (Houghton et al., 2001) are stated to
be the primary human impact of urban climate change which also contributes to land
surface warming. These two factors are inseparable as both contribute to rise in daily
mean temperature in urban areas (Gallo and Owen, 1999; Pielke et al., 2002). The
urbanization in Lahore has led to a massive increase of housing units, public places,
industrial activities and development of commercial areas, and deforestation, and it has
resulted in an increase in the overall land surface temperature of Lahore (Qureshi et al.,
2012). The significance of this study is to highlight the usage of satellite remote sensing
and GIS techniques in evaluating urban expansion of Lahore and to examine its impact on
land surface temperature.
1.2. Background of the Study
Urban expansion is ascribed to growth of urban population, increase in the
number of factories, industries and vehicles and they emit greenhouse gases that affect
climate change drastically ranging from land surface to atmosphere (Sun et al., 2010).
Urban expansion is the most significant human activity, producing massive impacts on
urban climate at the global, regional and local levels (Landsberg, 1981, Turner et al.,
1990) and it has become a formidable challenge to retain healthy environment while
attaining sustainable development (Fan et al., 2009). Rapid urban sprawl has changed
landscape with serious impact on urban climate as well as cultural, economic and social
setup of the societies. Spatio-temporal urban expansion patterns are crucial to
comprehend their effects on surface temperature. Urban expansion is determined by
socio-economic development and population growth of urban area (Liu et al., 2002;
Lopez, 2001; Wilson et al., 2003). Urban expansion has also led to environmental and
ecological problems such as increase in land surface temperature and major reduction in
vegetation cover (Ifatimehin and Ufuah, 2006).
Land surface temperature is a key geographic phenomenon to be examined for
thorough understanding of environmental and climatic changes taking place all over the
world. Land surface temperature is defined as temperature detected when the land surface
is touched with the fingers and surface temperature is the skin temperature of the land
4
surface (Rajeshwari and Mani, 2014). It is the temperature released by the surface of land
and measured in kelvin. It can be acquired from satellite images or direct measurement.
LST equips with accurate measurement to indicate the energy exchange balance between
the atmosphere and land surface (Zhengming and Dozier, 1989; Zhengming, 2007). It is
significantly affected by land use changes and increasing greenhouse gases in the air. All
the chemical, physical and biological processes taking place on the earth surface are
controlled by LST (Ruiliang et al., 2006). The study of LST is of pivotal significance to
study human-environment interaction and urban climate because of its spatial and
temporal resolution observed within environment of a city (Stathopoulou and Cartalis,
2009; Weng, 2009).
There is a general consensus that the urban climate can significantly be changed
due to urban expansion and anthropogenic activities. It is observed that the human
activities such as urbanization, agricultural systems, pollution, and deforestation have
accelerated severe climatic changes (Coltri et al., 2009). The most domineering problem
of increasing surface temperature is due to urban expansion alteration and conversion of
vegetated surfaces to impervious surfaces. These changes have great effects on the
absorption of solar radiation, land surface temperature, storage of heat, evaporation rates
and can radically alter the conditions of the near-surface atmosphere over the urban areas
(Mallick et al,. 2008).
One of the key modifications prompted by the urban land expansion is vegetation
cover altered into the asphalted and concrete constructions on a large scale. Subsequently,
the thermal characteristics of the urban area and impervious surface undergo a change.
(Srivanit, 2012). The consumption of heat absorbing materials used in construction (e.g.,
asphalt, stone, concrete and metal) and construction of pavements, roads, footpaths,
terraces and parking lots in cities and the consistent decrease in the area of natural
vegetation, agricultural land and water bodies produce higher temperature in cities which
apparently is a localized phenomenon but it contributes to global heat as well (Joshi and
Bhatt, 2012). The increased urban temperature leaves adverse impacts on climate, like
modification of precipitation patterns, higher pollution level and manifold consumption of
energy for air conditioning. Urban Heat Island (UHI) effects are of prime concern
regarding the studies of urban climatology for magnitude and variation of land surface
temperature in urban areas (Srivanit, 2012).
5
It is stated in the fifth assessment report of The Intergovernmental Panel on
Climate Change (IPCC) that cities are principal contributors in raising the global average
temperature and climatic change. It has also been demonstrated by the estimates in the
related studies by IPCC that the global climatic change in the next decade will be
principally due to human dwellings, use of fossil fuel and its combustion (Houghton et
al., 1996; 2001). Assessment report by IPCC states an average increase in temperature by
0.6°C in the last century. The increase is further projected to be of 1.4ºC to 5.8ºC by the
end of 21st century (Parry et al., 2007). The IPCC report for the year 2007 indicates
increase in methane, carbon dioxide and nitrous oxide, mainly caused by industrial and
anthropogenic activities (Parry et al., 2007). The urban heat island effect is contributed by
the anthropogenic activities, including human demand of goods, increasing industrial
activities, use of vehicles, process of proving heating and cooling systems in domestic use
and activities pertaining to economic gains (EPA, 2003).
The temperature of cities all over the world is gradually rising due to urban
expansion (Jusuf et al., 2007). The drastic reduction in the vegetated areas in the cities is
one of the possible causes (Kumar et al., 2012). Land surface temperatures in cities have
long been area of research with a function of land use change, anthropogenic activities
and urban morphology, as core meteorological parameters (Mohan et al., 2013). The
Spatio-temporal change of land surface temperature is the most prominent existing issue
of apprehension in urban areas of both developing and developed countries across the
globe (Mohan et al., 2012). Cities like, London (Authority, 2006), Tokyo (Ooka, 2007)
and New York (Cox, 2011) have long been subjected to climate change and altered by
phenomenon of urban heat island. However, with increasing industrial activities and
urban development, urban heat island pockets are also being identified in all populated
areas as well as developing cities like Ethiopia (Kifle, 2003), Mexico (Garcia et al.,
2007), Nigeria (Akinbode et al., 2008), Malaysia (Takeuchi et al., 2010), Oman (Charabi
and Bakhit, 2011), Argentina (Camilloni and Barrucand, 2012), and others. In Pakistan,
Spatio-temporal changes of surface temperature in big cities like Karachi, Lahore,
Faisalabad, Rawalpindi, Multan, Gujranwala and Islamabad, are being examined in the
last few years (Qureshi et al., 2012; Afsar et al., 2013).
The utilization of GIS and satellite remote sensing has been demonstrated as an
effective technique of making assessment of urban expansion, its location, and rate of
6
expansion, trend, amount and possible effects on environment such as urban climate
(Weng, 2001). As satellite remote sensing is a quick means for acquisition of data
encompassing a large area, it is a useful technology for gathering observations regarding
urban expansion and mapping distribution patterns of surface temperature (Lopez, 2001).
Remote sensing techniques provided an opportunity to estimate temperature from the
thermal band of infrared Landsat images (Sun et al., 2004). The range of infrared heat can
be detected through sensors equipped in satellites. Estimation of land surface temperature
from satellite infrared radiometers has been beneficial (Prasad et al., 2013). The
techniques of RS are extensively applied for identifying land surface temperature and
observing urban expansion at numerous scales with valuable results (Weng, 2002). This
study is to monitor the urban expansion of Lahore and to examine its impact on land
surface temperature.
1.3. Statement of the Problem
Urban expansion, both in terms of population size and land use changes, areal
extent, and anthropogenic activities, is the most definite outcome of human alteration of
vegetation areas to built-up surfaces in urban areas (Weng, 2001; Xiao and Weng, 2007).
This change contributes significant effects on local climate and urban temperature
(Landsberg, 1981). One of the familiar phenomena of urban heat island exhibited is that
the temperature in cities is a few degrees higher than the nearby country side. The
presence of UHI raises temperature in cities as compared to their surroundings of country
side (Voogt and Oke, 2003). Agricultural lands and forests are converted into urbanized
structures including roads, pavements, parking lots, buildings, and other impervious
structure. They usually have a greater thermal conductivity and higher solar radiation
absorption capacity in urban areas. The heat during day time is stored and released at
night (Weng, 2001). Therefore, urban areas experience a comparatively higher surface
temperature than rural suburbs. This thermal difference, along with the transportation,
industry, heat emitted by the urban communities contributes to the accumulation of heat
island and increasing land surface temperature in urban areas.
Lahore, has experienced remarkable growth, expansion and developmental
activities e.g. buildings, road networks, deforestation, increasing economic activities, the
formation of strong administrative establishment and accumulation of social services i.e.
7
education, health, cultural and recreational, numerous anthropogenic activities and they
have serious repercussions on the urban climate of the city of Lahore. Since independence
(1947), the enlargement of the built-up area of Lahore has been remarkable and is still
gaining momentum, especially in the last two decades, it has been noted to be expanded
to a significant extent as shown in Table1.1 (JICA, 2011). The spatial growth of Lahore
has been mostly contributed by the accretion of a few developed planned areas, but most
of it has been a subject to haphazard developed parcels of urban land. The overall urban
expansion resulted in unprecedented urban growth and enlargement of the city
boundaries. The previous residential areas are renewed in commercial centers while the
suburban population is continuously moving towards outer skirts because of the
expansion of city (Riaz, 2011). The jurisdictional limit of Lahore Development Authority
is extending continuously, resulting in spatial friction, traffic congestion, accidents,
pollution, increasing land surface temperature and many more problems. The urban
climate of Lahore is affected by the rapid growth of urban expansion.
Since the 1950s, urban development pace has been accelerated because of greater
accumulation of urban population and economy. The urban expansion of Lahore has been
steady since 1951 to 1981, but it has expanded enormously without any limits since
1980s. The major growth started around late 1960’s when the population growth rate was
very high (JICA, 2011). This high growth leads to the urban expansion in the south and
south-west corridors of Ferozepur Road and Multan Road, again mostly unplanned
suburbs, with the exception of rich areas like Model Town, Gulberg and Shadman. In the
east of the city, urbanization has been limited due to proximity of India, and was seriously
affected after the 1965 war. Similarly, westward expansion has been restrained due to the
Ravi River. During the period between 1970s and 1980s, urban population exceeded 02
million, forming Lahore into a metropolis (JICA, 2011). Urbanization in Lahore started to
boost up around 1980s.
The massive urbanization in Lahore through housing colonies, commercial and
industrial regions, infrastructure, transportation projects and rapid urban growth of
population has created impact on urban environment and climate, with considerable
effects on land surface temperature (NESPAK, 2010). According to 1998 Census of
district Lahore, population and built-up area of Lahore increased. The administrative
boundary was revised in 2005 with respect to population and built-up areas (GoP, 2000).
8
Several new housing schemes and commercial areas were also approved by Lahore
Development Authority during the period of 2000 to 2015. It is estimated that almost
12.7% of total urban population of the country is residing in the city of Lahore, while the
city of Karachi contributes 21.7% (Jan et al., 2008). In the province of the Punjab, 22% of
the urban population resides in Lahore, and half of the total provincial urban population
lives in five big cities (Arif and Hamid, 2007).
Table 1.1: Urban Development of Lahore
Description Urban Built-up Area (km2
) Average Growth Area Per
Year in km2
Pre-British Rule 1.105 -
British Period 23.8 0.45
1850 – 1900 68.7 0.89
1901 – 1950 71.2 0.48
1951 – 1965 117.2 3.23
1966 – 1980 175.7 3.90
1981 – 1990 245.6 6.98
1991 - 2000 326.0 8.04
2001 - 2006 397.8 11.96
Source: JICA, 2011
According to the PCO, the population of Lahore in 1998 was 6.3 million (GoP
1998) and 80 per cent of it dwelled within a diameter of 72 km. Most of the population is
concentrated around and within the heart of the city and then a gradual diffusion in a Peri
urban areas is observed with overall average density of 120 people per acre (NESPAK,
1997). In 2012, it was estimated to nine million (GoP, 2012). In 2015, it was estimated to
increase to 9.5 million (GoP, 2015). The growth rate of Lahore is alarming as its
population density has multiplied from 640 to 5386 persons residing in one square
kilometer from 1951 to 2015 respectively. 82.2 per cent population is urbanized and 17.8
per cent is rural (Almas et al., 2005; GoP, 2015).
The land use changes, rapid growth of population, lack of well managed public
transport, increasing number of private automobiles and facilities of life adversely affect
the climatic condition of Lahore. The main factors responsible for the increase of the land
surface temperature in Lahore are industrial activities, development of the commercial
areas, construction of road infrastructure, housing schemes deforestation and combustion
9
from the vehicles and increase of greenhouse gases (Qureshi et al., 2012). Owing to
expansion in built-up area and rapid urbanization, the temperature of Lahore has
significantly increased from 1950 to 2015 (Figure 1.3 and 1.4).
In this research, satellite remote sensing techniques are applied to evaluate urban
expansion and its influence on the land surface temperature of Lahore. It is examined to
see the loss of agricultural land and vegetal cover, expansion of urban land and land use
land cover changes along with role of industrial development in the sprawl of Lahore and
its effects on urban temperature. Various studies have demonstrated the effects of land
use land cover changes in different regions in the world on LST (Keramitsoglou et al.,
2011), the present study figures this relationship in the city of Lahore, Pakistan.
Identifying Spatio temporal correlation between changes in land use and estimation of
land surface temperature can be beneficial in predicting future land warming. The present
research is an attempt to provide scientific information to urban planners, geographers,
resource managers and environmental experts to maintain natural landscapes and manage
sustainable and healthy environment (Zhou et al., 2011).
In the present research, various remote sensing techniques such as supervised
images classification and indices such as Normalized Difference Built-up Index (NDBI),
and Normalized Difference Vegetation Index (NDVI) (Chen et al., 2004; Hawkins et al.,
2004; Wang et al., 2004) would be used to extract land use change from satellite images
for the period from 1973 to 2015 and evaluated and the land surface temperature of
Lahore would be analyzed and retrieved from the thermal infrared band of Landsat
satellite images (Yuan and Bauer, 2005) for the period from 1990 to 2015. Landsat data is
used for mapping of land surface temperature variation and impact assessment of urban
expansion using suitable algorithm. To estimate the thermal condition of land surface
through satellite imagery, it is pertinent to work out the relation between the land
surface temperature and the urban expansion (Hawkins et al., 2004). The Normalized
Difference Built-up Index and Normalized Difference Vegetation Index (Myneni et al.,
2001; Chen et al., 2006) have been applied to investigate the correlation between thermal
behavior and impervious structure and amount of vegetation cover. This study is an
attempt to evaluate the expansion of urban land and estimate its impact on land surface
temperature of Lahore with the help of a time series of satellite images by using remote
sensing techniques.
10
1.4. Hypothesis of the Research
The hypothesis of this research i.e.; in Lahore, “due to Land use changes and
consequent urban expansion, the land surface temperature has significantly been altered
during the last three decades” which has caused a number of environmental problems in
the study area.
1.5. Aim of the Study
The present study aims at utilizing both readings of temperature from satellite
based LST and meteorological measurements to assess the effects of urban expansion on
land surface temperature changes over Lahore applying GIS and RS techniques. In situ,
observations at fixed stations provide better temporal resolution of data, while satellite
observations can provide better spatial coverage (Mohan et al., 2013). In order to develop
a deeper understanding of urban heat island phenomenon and land surface temperature ,
observations recorded by MET station and satellite imagery have been compared by the
utilization of both fixed station (Urban and Rural) temperature data as well as satellite
thermal infrared data can supplement the weaknesses and strengths of each other. Surface
temperature derived from thermal imagery has been noted to have better accuracy and
precision with lower bias and relatively stronger correlation when compared to in-situ
temperature observations, therefore, thermal imagery has been utilized to retrieve the land
surface temperature (Hung et al., 2006; Fung et al., 2009). The incorporation of two
techniques namely remote sensing and GIS is observed to be efficient and reliable in
monitoring, analyzing and evaluating urban expansion and its impact on land surface
temperature of Lahore.
1.6. Objectives of the Study
In order to test and explore the above-mentioned hypothesis, following research
objectives are sought: The explicit objectives of the proposed study are enumerated below
1. To highlight urban expansion process of Lahore in a specific time period and
analysis of spatial and temporal changes taking place through sequential mapping.
o To monitor the urban expansion during the period under study i.e.; 1972 to
2015 using Landsat satellite images.
11
o To monitor and analyze the dynamic change of urban land use in Lahore
from 1972-2015
2. To evaluate temporal change in the land surface temperature using satellite
thermal imagery from 1990 to 2015
3. To study the land surface temperature variations of different types of land use
from 1990 to 2015
4. To identify temporal changes in atmospheric temperature trends of Lahore using
meteorological data from 1950 to 2015
5. To explore the relationship between land surface temperature and NDVI, NDBI
using satellite imagery from 1990 to 2015
1.7. Research Questions
The study pays attention to answer the subsequent research questions
i. What urban expansion has occurred in Lahore from 1972 to 2015?
ii. Does urban expansion have any effects on land surface temperature of Lahore?
iii. What are the changes between land use type (e.g. built-up area and vegetation)
and land surface temperature?
1.8. Study Area
Lahore commands geostrategic, geopolitical and administrative role as the Capital
of Punjab province, Pakistan and the 2nd biggest City of Pakistan in terms of population
of about 10 million (JICA, 2011). It is located at the north-eastern part of Pakistan with its
Centre lying with 25kms of the International Border with India (Figure 1.1) (NESPAK,
2004). Lahore boasts a history of nearly 1000 years (GoP, 2000). The city of Lahore,
being one of the ancient cities of Pakistan and provincial capital, operates administrative
functions regarding health, education, culture and transportation along with its urban
hierarchy in trade and industry, stands 2nd in commerce (Riaz, 2011).
Lahore lies to the western side of the River Ravi at level flood plain. Sloping
towards the active course down slop north to south. Lahore lies between 74°-01’ and 74°-
39’ east longitude, and 31°-15’ and 31°-42’ north latitude (Figure 1.1). Lahore is ranked
12
fifth in South Asia and thirtieth in the world. It is also the 2nd largest as well as 2nd most
populous city of Pakistan. It has grown the historic route linking central Asia with sub-
continent (NESPAK, 2004). Lahore is bounded by Sheikupura district in the west and by
Wagha on the east, while on south it is surrounded by the Kasur district and on the North
side it is bordered by Ravi River (JICA, 2011).
Figure 1.1: Geographical Location of the Study Area (Lahore)
Minallah, 2016 (Edited)
The administrative structure has been a subject to change after declaration of
Local Government Ordinance in 2001. Administrative bodies for Districts, City Districts,
Towns/Tehsil and Union Councils have been created. Lahore was declared as City
District and was further divided into six towns. In 2005, six towns were split into nine
towns in City District Govt. Lahore. Now, Lahore City District comprises following nine
towns (Fig. 1.2) which are administrated by Town Municipal Administration (TMA). The
Lahore cantonment is distinctly governed by cantonment board and the provision of core
facilities is the sole responsibility of Lahore Cantonment Board (JICA, 2011). Today, the
area of the Lahore is spread over 1,772 km2.
13
Figure 1.2: Administrative Towns and Urban sub regions of Lahore
Minallah, 2016 (Edited)
1.8.1. Physiography
The city of Lahore can be divided into two parts; low lying alluvial soil and
upland area. The low lying area is found along the River Ravi, while the upland area is
located in the east, away from the River Ravi, occupying the total area touching the
Amristar border at the east of the district. The low lying areas are generally flooded
during the monsoon season by the water of the river Ravi. The flow of the river Ravi is
directed along the boundary of Lahore district with Sheikhupura district. The urban
development and the construction of infrastructure destroyed or changed the
physiographic features of Lahore, including levees and channel remnants etc. The
confinements of the flood plains along the river Ravi have been constructed by
embankments (bunds) and spurs. Moreover, the sewage drains have replaced the
Meandering channels. The area subjected to the sub-recent flood plain is measured to be 4
to 8 meters as compared to the areas subjected to the recent flood plain like places
including Mughalpura, Shalimar Garden and Multan road (IMPL, 2004). The plain slope
of the upland is from north-east to south-east. The low land lying to the south is termed as
Hithar. The soil available in the area of low lying is easy to be filled, rather sandy in
terms of fertility.
14
1.8.1.1. Topography
Lahore is located naturally having no mountain or hills between the central
uplands and low lying alluvial land of the river Ravi. The alluvial land of the district
Lahore can further be divided into 1) Uttar and 2) Hithar. Uttar comprises the almost 2/3
of entire land in the north. On the other hand, the low lying area of Hithar is generally
flooded during the monsoon season by the high flow in the river Ravi. The height above
sea level of the area is calculated to be 150 to 200 meters.
The soil of Lahore is analyzed to be different in character and prone to be dry.
However, the soil is fertile enough for the plant nutrients. Irrigation in the area is
dependent on the water supply from canals as rainfall is precarious; water level in the
wells is lower and quality is saline. The level of the water where it is suitable for
irrigating purposes is lower for the tube wells. There is also a variation in the depth wise
chemical composition of the elements in water of different areas of Lahore. The suitable
potable water for drinking purposes is found in the surrounding areas covering a belt of 5
miles to 20 miles in the vicinity of the river Ravi. In the Hithar areas, the supply of water
for irrigation is non-perennial and the deficiency is made up by installation of tube wells.
The soil is alluvial and soft, while in some areas, loam is yielding but also sandy and
fertile.
1.8.2. Climatic Conditions
1.8.2.1. Temperature
Lahore city has extreme climate. According to Koppen Classification System,
Lahore experiences semi-arid climate with hot and rainy summers and mild winters. It
experiences four seasons which include summer (June-Aug) with dust rain storms, heat
wave days, Rainy Monsoon and dry but pleasant Autumn (Sep-November), winters (Dec-
Feb) with few western disturbances causing rains and hot dry spring (March-May)
(Heiden, 2011).
The summer season sets in April and continues till September. The hottest months
are May, June, and July. The mean minimum and maximum temperatures of Lahore
during these months vary between 27.3°C and 40.4°C as shown in Figure 1.3 (NESPAK,
2004). From mid of July to September, Monsoon rains become a cause of comparatively
pleasant weather. The winter season starts from November to March. Extreme cold
15
weather is experienced from December to February with minimum temperature almost
reaching down up to the freezing point. The mean minimum and maximum temperatures
during these months varies between 5.9°C and 22°C respectively (NESPAK, 2004). The
minimum temperature of Lahore falls below zero degrees Celsius. Sometimes, maximum
temperature reaches around 50 Degrees Celsius (JICA, 2011; PMD, 2015).
Table. 1.2: Mean Temperature (°C) and Precipitation of Lahore 1950-2015
Month Mean Temperature (°C) Precipitation
(Millimeters)
Relative
Humidity (%) Minimum Maximum MAT
January 6.5 19.2 12.9 23.0 64.6
February 9.5 22.2 15.9 28.5 57.6
March 14.6 27.4 21 41.2 51.1
April 19.9 34.1 27 19.7 37.9
May 24.4 38.9 31.7 22.4 31.9
June 27.4 40.1 33.8 36.3 39.8
July 27.0 36.8 31.9 202.1 63.3
August 26.6 34.9 30.8 163.9 68.8
September 24.7 34.8 29.8 61.1 59.6
October 18.9 32.7 25.8 12.4 53.2
November 12.1 27.3 19.7 4.2 61.4
December 8.4 21.6 15 18.9 67.8
Annual 18.3 30.8 24.6 628.7 54.7
Source: Pakistan Meteorology Department Lahore, 2015
Figure 1.3: Mean Monthly Temperature (°C) of Lahore from 1950 to 2015
Source: Pakistan Meteorology Department Lahore, 2015
0
5
10
15
20
25
30
35
40
45
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Tem
pera
ture
(°C
)
Month
MXT MNT MAT
16
Figure 1.4: Mean Annual Atmospheric Temperature of Lahore from 1950 to 2015
Source: Pakistan Meteorology Department Lahore, 2015
1.8.2.2. Rainfall
The city has light to moderate rain fall during January and February, which is
succeeded by a spell of pleasant spring weather. In April temperature starts rising and two
succeeding months are quite hot. Dust storms occur occasionally during this season
relieving temporarily the intensity of the heat. Towards the end of June, monsoon starts
and during the following two and a half months, spell of rainy weather alternates with
intervals of sultry weather (GoP, 2004). Lahore reports maximum rain during the month
of July (Figure 1.5). Maximum rainfall in a single day in Lahore was recorded to be 8.7
inch (221 millimeters) on August 13, 2008 (PMD, 2010). A Table 1.2 displays monthly
average precipitation and mean minimum and maximum temperature recorded at Lahore.
1.8.2.3. Humidity
Relative humidity in the winter is higher as compared to the summer season. May
and June are dry and very hot accompanying dust storms. Monsoon season sets in the end
of the June or at the beginning of July, characterized by humid sultry weather and heavy
downpour. July, August and September are practically suffocated in the year. The
variation in the relative humidity throughout the month is shown in the Table 1.2.
y = 0.0128x - 0.821
R² = 0.185923
23.5
24
24.5
25
25.5
26
1950 1960 1970 1980 1990 2000 2010 2020
Tem
para
ture
An
om
aly
(°C
)
Year
Lahore Temperature Linear (Lahore Temperature )
17
Figure 1.5: Climograph of Lahore based on 65 Years Climatic Data
Source: Pakistan Meteorology Department, Lahore, 2016
1.8.2.4. Wind Speed and Direction
Winter season in Lahore has minimum wind storm and is mostly calm. During the
months of April to July, wind storms are common. The maximum occurrence is recorded
in June when high temperature develops low air pressure. In winter, the direction of the
wind flow is from north-west, while in summer, it is directed from the south-east which
18
causes monsoon rains. The predominant direction of the wind in Lahore is north-west,
while it is south-west in the monsoon season.
1.9. Significance of the Study
This research aims to empirically analyze urban development and its consequent
impact on temporal land surface temperature of Lahore since 1951. Land use patterns of
Lahore have changed tremendously due to urban population growth and boost in
industrialization and commercial activities from 1951 to 2015. Industrial development
along with rapid urban expansion has caused increase in built-up area, loss of agricultural
land and deforestation resulting in change in overall environmental conditions and
increase in the land surface temperature of Lahore. Urban areas are the signs of
development and major agglomeration of human resource evolution. It is pertinent to
point out that no geographical study has ever been carried out in the context of evaluation
of urban expansion and its consequent impact on the urban climate of Lahore. Urban
expansion, land use changes and its effects on land surface temperature are examined
through remote sensing procedures.
Scholars such as Weng, (2001), Xiao et al., (2006), Zemba et al., (2010), Xu &
Min, (2013), Stemn, (2014) and Yang et al., (2014) have already focused on the remote
sensing application in urban analysis to find out the spatial relationship between the urban
expansion and LST within the limits of the cities. Therefore, the proposed study is very
significant in this regard as population growth and built-up area of Lahore have increased
manifold since 1951. This study identifies the population pressure on different areas of
Lahore to work out a relationship between population and urban growth and temperature.
The research related to urban expansion will be productive in improving the urban
dwellers’ standard of living, making sure the civic amenities and meeting the needs of
basic services and housing infrastructures for them. The facts of the phenomenal urban
sprawl and the patterns of land use can be beneficial for the decision makers in terms of
policy making and urban planning for the betterment of inhabitants of the city. The facts
revealed in the study are helpful in making settlement plans before the commencement of
the mega projects in Lahore. It will cope with the difficulties of urban developments.
The increase in temperature in the present millennium is inviting researchers to
conduct studies in this regard. LST gives vital information related to surface physical
19
properties and the urban climate that is crucial to environmental processes. It also
supplements to recognize how and to what extent the factors are contributing to the
climate change of an urban area. Furthermore, comparisons can be made after the analysis
of temperature rising rates with the temperature of the other areas to investigate natural
and anthropogenic activities in the region. The fluctuation in the temperature and
information about the changes are required to foresee potential effects of such changes on
water resources, energy, health, agriculture and industrial sector. LST statistics could
facilitate urban planners particularly for better understanding of urban climate along with
seeking solution for the management of urban environment. The results acquired through
present research suggest that land use changes have crucial effects on the indigenous
climate of Lahore, which can be helpful in prediction of land use and regional climate
change patterns in future. Remote sensing data are of a great value in terms of calculating
LST in this research as this method extends the skills to collect data over a vast area at the
one and same time. In urban area comprising hundreds of Km2, it might not be possible to
obtain land surface temperature measurements especially across the whole area in a great
number at the same time in a ground survey. If such a survey would have been regulated,
it would further demand the extensions of it to a large area. Satellite images capacitate to
obtain a large area coverage simultaneously.
The results and findings of this research can be generalized for other cities of
Pakistan. The other benefit of this research will be that it can be used as a reference
research document. All the basic information is presented in tables, charts, figures and
maps. All the maps are prepared in GIS environment with the rapid urban growth and
population explosion in Lahore. The research findings are to be considered by the city
managers to develop the city systematically; only up-to-date land surface temperature
information of town planning can make our research area healthier, more habitable and to
certain extent even a great industrialized city. This study offers a deeper insight of the
issues confronted by urban dwellers because of population growth. This study may be a
valuable addition for the planners and researchers at the same time for forecasting and
choosing between numerous substitutes. At technological, theoretical and application
level, this study is highly beneficial. The significance of GIS, satellite remote sensing and
image processing techniques in detection of land use change and urban studies
emphasizes the technological trait of the research while theoretical level of this study
exhibits the development and growth of urban area and population and detects changes in
20
urban land use. It is facilitating us with an intellectual approach towards the issue of
urban expansion and this approach can be beneficial for the future researchers. At
application level, the transformation of agricultural land into urban built-up area and land
surface temperature variations have been identified. This study examined the land surface
temperature variations and spatial expansion of urban physical structure of Lahore which
is an additional perspective of the theoretical framework of urban studies.
The same issues relating to the urban expansion and necessities are being faced by
the other major and big cities of Pakistan. The similar methodology can be opted to probe
into the problems of urban expansion in the other major cities of Pakistan in order to
detect the intensity of urban expansion and the urban land use changes and its impact on
land surface temperature. The procedure adopted in the present study can be utilized as a
substitute to the traditional and conventional empirical observation in-situ data used for
climatic change and environmental studies. The conclusion arrived through the
application of GIS and remote sensing imageries has long been proved beneficial for
urban expansion monitoring, land use change analysis and mapping land surface
temperatures.
1.10. Thesis Organization
The organization of the research work is divided into six chapters. The first
chapter provides the introduction to research, background and statement of the problem. It
gives the detailed hypothesis, aim and objectives of the study and research questions of
the present study. It also represents the description of the study area dealing with the
physical nature and climatic conditions of the research area. It also provides the
significance of the study and thesis organization. The second chapter deals with the
review of literature including urban expansion and related land use changes, use of
remote sensing for assessing urban expansion and urban climate pattern. It also describes
the utilization of remote sensing data to compute radiant surface temperature, and also
provides literature on the relationship between the LST and NDBI, NDVI.
The third chapter is categorized into data sources and methodology. A brief
description of the sources and data acquisition techniques and quality of data has been
presented in third chapter data source section. The methodology section delineates the
conceptual framework as well as techniques and procedure followed during the present
research. The methodology section of the third chapter also provides detail about the GIS
21
and remote sensing techniques in monitoring and analyzing Spatio-temporal urban
expansion of the city of Lahore and estimate of the LST.
Figure 1.6: Thesis Organization Flow Chart
Minallah, 2016
The chapter four of this thesis includes the analysis of the population growth of
Lahore from 1951 to 2015. It describes the historical expansion of Lahore. It also narrates
the Spatio-temporal urban expansion of Lahore from 1951 to 2015 using a time series of
Landsat imagery from 1973 to 2015. It highlights the land use changes associated with
urban expansion occurred from 1951 to 2015. Chapter five of the thesis deals with the
remote sensing techniques to identify the land surface temperature variations of Lahore
22
and impact of urban expansion. The basic steps to be followed are derived from the
estimation of land surface temperature by using satellite thermal images. The chapter five
also describes the comparison based on the results derived from Landsat images of
surface temperature and Spatio-temporal urban expansion of Lahore. In the end, the last
chapter 6 of the thesis provides a summary and concludes the study with recommendation
drawn from the analysis.
23
CHAPTER 2: URBAN EXPANSION AND ITS IMPACT ON
LAND SURFACE TEMPERATURE: A REVIEW
2.1. Introduction
The present study aims at evaluation of the pragmatic works pertaining to the
urban expansion with reference to land surface temperature using satellite remote sensing
techniques. Review of the previous literature and work done in the field provides a
guideline in designing the scientific studies through the identification of the broken links
and gaps in previous studies and provides basis for innovative research. Gradually but
steadily, industrialization, economic development and rural to urban migration and
contributing factors have shaped urban centers and cities anew by expanding their
original administrative limits across the world. Subsequently, the result of urban
population growth is overcrowded cities and loss of agricultural land adjoining the city.
The shift of rural area into urban built-up ensuing from population increase and economic
development taking place is alarming presently. Lately the urban areas cover only almost
3% surface of the earth and effects of urban expansion on the environment processes are
long-lasting on the global scale along with climate change (Grimm et al., 2000; Griffiths
et al. 2010).
Urban expansion tends to bring surface modification, land use change and the
structure and components of the atmosphere. These modifications yield results and show
diverse micro and meso scale urban climates which are unusually warmer unlike the
original climate of the country side. For instance, the cities have higher temperatures and
less strong wind than that of country side. The concentration of people and anthropogenic
activities in cities produces an “island” of higher temperature surrounded by a “sea” of
cooler country side, the urban and rural areas temperature differences are typically named
as the urban heat island phenomenon (Oke, 1992). LST is an important parameter for
recognizing urban micro-climatic changes and their Spatio-temporal variations related to
the urban environment.
The relationship between urbanized areas and their atmospheric and land surface
temperature has been demonstrated in invoking interest in geographers and environmental
scientists as well as in the government within academia. Geographers are primarily
24
concerned with impacts of anthropogenic activities on urban environment (Viterito,
1991), while many environmental scientists are concerned with how the UHI
Phenomenon exercises effects on the state of environment and how is itself affected by it
(Gartland, 2008). The review of literature in this connection is as follows.
2.2. Urban Expansion and Land use Changes
Urban geography deals with the evolution, location and spatial morphological
arrangement of cities. It emphasizes upon the study of cities and towns in terms of
population concentration, infrastructure and their impact upon economy, environment and
urban climate. Urban geography is a branch of Human geography that is a branch of
geography which shapes spatial distribution of human phenomena and economic
activities with their particular environment. Urban expansion focuses on growth of
population and physical expansion of towns and cities. In the present world, a common
man considers urban growth, expansion and sprawl synonymously but they are dissimilar
as urban growth is an amount of increase in developed and built-up land, infrastructure
increase of cities is expansion and increase in spatial features (typically has a negative
connotation) is urban sprawl which is uncoordinated growth (Bhutta, 2010).
Urban expansion is a major human activity that instigates massive influences on
urban environment at different scales (Jothimain, 1997; Turner et al., 1990) and it has
become a serious managerial issue as for as urban planning and sustainable management
is concerned. Socio-economic development and population growth trigger urban
expansion (Epstein et al., 2002; Wilson et al., 2003). A number of studies focus on urban
expansion in developed countries (Seto et al., 2002; Liu et al., 2002;) as well as
developing countries, like India, Pakistan (Barrens et al. 2001; Lata et al., 2001; Weng,
2001; Sudhira et al., 2003; Ghaffar, 2006; Shirazi, 2011; Anwar and Bhalli 2012; Khan,
Arshad and Mohsin, 2014; Bhalli and Ghaffar, 2015), China (Kaufmann and Seto, 2001;
Seto et al., 2002; Weng, 2002; Seto and Kaufmann, 2003; Cheng and Masser, 2003; Xiao
et al., 2006), and Mexico (Muoz-Villers and Lpez-Blanco, 2008).
As the world continues to become gradually urbanized, the earth’s land surface
continues to alter. Land Use Change (LUC) data is most essential for many fields of
science, urban land use planning, decision making and management. Land use refers to
“what people do to the land surface”. For example, agriculture, residential land uses,
25
commercial and industrial land. While the land cover refers to the “type of material
present on the landscape”. For example, water, forest, cotton fields, asphalt and concrete
highway (Jensen, 2005; Lillesand et al., 2007). Although environmental scientists and
geographers are concerned with the extent of land cover type change happening with the
passage of time on the Earth’s landscape (Mas, 1999); they are also alarmed at the
climatic influences of land use change (Chuvieco, 2008). One of those impacts is the
urban heat island phenomenon and higher overall temperature (Quattrochi et al., 1997;
Harwood, 2008).
Urban expansion is a form of urban growth taking place in various phases,
increasing the residential density, creating new urbanized land and redevelopment,
conversion of non-urban land into built-up areas (Angel et al., 2005; Bhatta, 2010). In
such advancements, the agricultural land, green spaces and vegetal cover, forests and
water bodies are encroached by the urban expansion. Urban expansion reduces the fertile
agricultural land by converting it into built-up areas (Khan et al., 2014). The
consequences of such conversion lead towards deforestation, water scarcity and urban
flooding, affecting the environment ecosystem and resulting in increase of land surface
temperature in cities (Puertasa et al., 2014).
The rapid population growth in urban areas is also one of the major reasons for the
urban expansion, extension of built-up areas for anthropogenic activities, development of
industrial areas along with commercial centers as experienced in the cities of developing
countries, like Lahore, Pakistan. Such kind of urban expansion and development occurred
haphazardly along unplanned new residential colonies and vicinities of the city.
Researchers argue on the changes occurred in patterns defining industrialization,
urbanization and economic activities as demographic and natural change (Khan et al.,
2014). These demographic and natural changes are major reasons initiating urban
expansion and the extension of built-up areas to cater the ever increasing population in
the city (Li et al., 2003). Thus, in the developing countries like Pakistan, the urban
expansion and the massive physical growth of the city can be attributed to the rapid
population growth. According to the UN report 2005, the population of the developing
countries with low income causes population explosion that is almost five time greater as
compared to countries that have developed already (UN, 2005).
26
In Pakistan, like other developing countries, the socio-economic problems of the
complex nature and climatic change are being created by the irregular pattern of the urban
sprawl at a very high rate. It is a fact that urban areas house 52% of the total population of
the world, although the urban areas occupy a small part of world’s land (PRB, 2013),
causing rapid threatening impact on natural environment and climate of urban areas
(Grimm et al., 2000; Haregeweyn et al., 2012; He et al., 2008). Resultantly, problems
including the deficiency of drinking water, squatter settlements, lack of better sewerage
facilities, overburdening of municipal facilities and conversion of fertile agricultural land
into built-up area are intensifying the urban scene, ultimately affecting the urban climate,
increasing the land surface temperature. Since many cities in Pakistan, especially the
bigger cities of the province of the Punjab are located in the heart of the most fertile land
including Lahore, Faisalabad, Rawalpindi and Multan, the expansion of urban land, is
therefore, a constant threat for fertile agricultural land, the supplies of food to cater the
ever increasing population in the future. The pattern of the urban population in Lahore,
Faisalabad and Multan specifically signifies the factors contributing the urban sprawl like
mass exodus from rural areas, natural increase of population, changes in the patterns of
the settlements, changes in socio-economic condition and improvements of the living
standards.
According to the census of 1981 of Pakistan, almost 24 million people were urban
residents which represent 28% of the total population of Pakistan. In Pakistan, 32.5 per
cent people were urban residents in 1998 which further increased 39.2 per cent in 2015
(GoP, 2015). In the Asia Pacific region, Pakistan has the major proportion of urban
population, 39.2 per cent, if compared with other countries of south Asia, which show
moderate urbanization level. Statistics show that by 2030 almost 50 per cent of population
of Pakistan would have be urbanized (GoP, 2015). Pakistan is urbanizing at an annual rate
of 3 per cent, the fastest pace in South Asian countries (Kugelman, 2013). A similar
pattern is discerned in the increase in urban population of the city of Lahore, as
mentioned in the previous studies conducted, indicating the increase in population and the
development of peri-urban vicinities. The increasing demand of housing facilities to
accommodate the ever increasing population and the conversion of the fertile arable land
into built-up structure have become the major concern over the past few decades. During
the last sixty six years, a massive development has taken place in the housing units,
contributing towards the increase in the land surface temperature of the city of Lahore.
27
2.3. Role of Remote Sensing in Assessing Urban Expansion
In geospatial science, satellite remote sensing observes the earth surface with
airborne sensors from space above its land surface. It has highly sensitive cameras which
not only operate through light, but produce images by utilizing other bands of
electromagnetic spectrum including microwave, infrared and ultraviolet. These airborne
and satellite sensors are located high in space, and can easily make images of large areas,
even a whole province. Observations related to earth through satellite images are
conducted from space by utilizing these sensors mounted on satellite (Bhatta, 2010).
Assessment of urban expansion with the help of geospatial techniques with
consistent acquirement of satellite remotely sensed digital data provides a broad visionary
approach to spatially organize urban land use and change detection analysis for the
sustainable urban development. The advent of satellite remote sensing technology
entertained a new horizon for assessing, monitoring and mapping land cover changes
along with empowering the researchers to predict future urban expansion more
technologically and efficiently than the conventional and traditional approaches (Maktav
and Erber, 2005). GIS and satellite remote sensing techniques seem to be a proper and
effective tool to present and recognize the urban growth phenomenon and are also utilized
globally for the analysis of urban expansion (Im et al., 2008).
Urbanization has numerous effects on the environment. With the rapid increase in
urban population, urbanized areas have also extended rapidly within the past several
decades (Goldblum and Wong, 2000). Many studies have examined that urban expansion
has produced localized increases in the land surface temperature as exposed by both long-
term analysis of satellite thermal data (Rizwan et al., 2008; Jiang and Tian, 2010;
Tursilowati et al., 2012) and analysis of ground based measurements (Kataoka et al.,
2009). Satellite remote sensing is a technique or tool that estimates electromagnetic
energy content present in a geographic area or an object from far by using sophisticated
sensors and then gathering important material from the satellite data utilizing algorithms
statistically and mathematically. Its utilities are integrated and synchronized with
mapping science tools, like cartography, GIS and other spatial techniques of data
collection (Bhatta, 2008). Spatio-temporal detailed information about urban morphology,
patterns of land use, distribution of population, infrastructure, and reasons for urban
dynamics are pertinent to be understood and observed. Urban satellite remote sensing
28
technique provides such type of information (Herold et al., 2004). Besides being an object
of challenge by spatial and spectral heterogeneity, satellite remote sensing seems befitting
source for collecting urban data (Jensen, 1999; Goldblum and Wong, 2000; Donnay et al.,
2001)
The fact is undisputable regarding earth observation being a modern science,
related with the studies of changing environment by using satellite remote sensing data
such as aerial photographs and satellite images (Bhatta, 2010). As Compared to similar
applications, satellite remote sensing of urbanized areas, is relatively a new methodology
for geographers and the remote sensing communal, particularly through space-borne
sensors (Maktav et al., 2005; Xu, 2008). Nonetheless, the interest of researchers and their
reliance on using the techniques of satellite remote sensing have shown a significant
intensification. The reasons for opting remote sensing are many; for instance, quick
acquisition of data for a large area, digital processing and respective analysis, integration
of GIS techniques and probability of getting temporal dataset (Bhatta, 2008).
The most valuable source used for monitoring urban expansion and mapping
built-up areas is remote sensing data, exclusively incorporating satellite remote sensing
system for various reasons (Xu, 2008; Bhatti and Tripathi, 2014). It provides a
comprehensive and synoptic view of enormous urban places, formally not imaginable to
get through simple field appraisals (Richards, 2013). Another major feature of utilizing
satellite remote sensing data is the accessibility of historical archives (Guindon et al.,
2004) helpful in understanding and mapping urban expansion over a span of time and for
urban analysis (Maktav et al., 2005; Griffiths et al., 2010).
Satellite images have also been extensively utilized for automated and semi-
automated mapping of land use change, water, vegetation, snow and other such
topographies (Joseph, 2005; Lillesand et al., 2004; Jensen, 2006). The techniques used in
formulation of image digital data can be categorized into two groups. The image
classification encompassing object based and pixel based methods comprises one group,
(Guindon et al., 2004; Cleve et al., 2008; Gao, 2008), whereas direct segmentation of
satellite images through indices comprise the second group (Zha et al., 2003; Zhang et al.,
2005; Knight et al., 2006). Each method imports definite limitations and a set of
advantages. However, indices precede the other classification methods in generating
results in short span of time.
29
Land cover data from satellite images is widely used in natural resource
management, environmental studies, and urban and regional planning. Some applications
are forest type mapping (Kennaway and Helmer, 2007), forest fire assessment (Mitchell
and Fei, 2010), Vegetation Drought Response Index mapping (Brown et al., 2008),
surface water estimation, land resource assessment, and urban green space delineation
(Lwin and Murayama, 2011). Moreover, land cover data serves as a primary form of
input bases in many geospatial models and spatial decision-support systems. In addition,
remote sensing data used in human settlement mapping are important for developing
countries where fine-scale GIS data are difficult to obtain. Human settlement mapping,
especially the detection of sparse urban, dense, industrial, and built-up infrastructures, is
important for population estimation, country resource assessment, urban planning and
monitoring of urban growth, and disaster management.
Numerous studies have utilized remote sensing statistics related to human
settlement such as house value estimation (Jensen et al., 2004; Wu and Murray, 2005),
population assessment (Liu and Herold, 2006; Yuan et al., 2008; Mao et al., 2012), slum
detection (Weeks et al., 2007; Kit et al., 2012; Kohli et al., 2012), urban population
density modeling (Joseph, and Wang, 2012), leaf index and household energy (Jensen et
al., 2003; Jensen et al., 2004), life quality assessment ( Nichol and Wong, 2006; Rashed
et al., 2007), urban growth (Cheng and Masser, 2003), and social vulnerability
assessment (Lu and Weng, 2007; Taubenböck et al., 2008).
Satellite remote sensing multispectral imagery and techniques have been useful
for several environmental analysis and monitoring the modification of land use, the
launch of the Landsat Earth observation satellite program since 1972 (Figure 2.1).
Satellite Remote sensing (SRS) imagery and data can provide essential information on
urban growth (Phinn et al., 2002; Jensen et al., 2004;), associated processes and their
effects on the urban climate and human environment, as well as observing the urban
expansion and spatial-temporal distribution of land use patterns (Ward et al., 2000;
Griffiths et al., 2010).
Satellite remote sensing thermal infrared data was not obtainable before the
launch of the Landsat 5/TM in 1982, due to low spatial resolution of other thermal
infrared sensors available. (Mallick et al., 2008). In 2013, Landsat 5/TM satellite was
decommissioned, and scan line corrector (SLC) failure was observed in 7/ETM+ satellites
30
Landsat imagery due to 22% drop in scanning (Figure 2.1). On 11 February 2013,
Landsat 8 satellite was launched successfully and it continues mission of earth
observation to date (Lulla et al., 2013; Tollefson, 2013).
The Landsat 8 OLI with 09 spectral bands (four visible, one near infrared, three
shortwave infrared) is stretched over a 185 Km swath including one panchromatic band
with a spatial resolution of 30 m and 15 m. (Maimaitiyiming et al., 2014; Yang et al.,
2014). Specifically, Landsat 8 satellite carried by thermal infrared sensor which sets up
two thermal infrared spectral bands 10.60–11.19 μm and 11.50–12.51 μm, respectively,
with a spatial resolution of 100 m by separating the thermal infrared wave band are
created on the proper Landsat 7/ETM+ (Irons et al., 2012). Therefore, to remove the
atmospheric effects, split-window algorithm can be utilized and then retrieve land surface
temperature with a relatively higher accuracy results (Yang et al., 2014).
Figure 2.1: Landsat Missions’ Timeline and their Current Status
Source: USGS, 2016
One of the reasons for high demand of satellite remote sensing data for urban
applications and analysis is the coverage of very large area encompasses. Remote sensing
data allows the researcher to study the large areas which may be very hard to access, and
it also delivers almost appropriate and actual material (Muttitanon et al., 2005). Spectral
and spatial high resolution images are also vital for land use observation as the sensor
may detect more mixtures of land use classes. Satellite remote sensing provides very large
archive of data covering time span of more than 40 years of observations (Reis, 2008).
31
No doubt, the limitations of optical remote sensing has sensitivity to atmospheric
conditions like a pattern of cloud may cover the area of study or so. In addition, the
resolution of the sensor limits the accuracy of results obtained from the satellite images.
The issues of urban landscape are complicated, featuring spectral and spatial
heterogeneity along with several surfaces of anthropogenic and natural origins which
create hurdles in analysis and further image classification creating large segment of mixed
pixels. In the course of time, the researchers studied that the acquisition of the data sets
was constrained and the researches had some limitations. First of all, there is a non-
availability of the cloud free and free of cost high resolution images of the study areas.
Secondly, as the Landsat imagery was introduced in 1973, and the earlier images had low
resolution. Thirdly, the deficiency of Landsat 7, the Scan Line Corrector (SLC) images of
the ETM+ sensor were rendered inadequately for the investigation of the LST and urban
expansion change detection studies.
There are several revisions on the usage of satellite remote sensing to screen urban
expansion and its impression on surface temperature variation (Jensen et al., 1993; Gatrell
and Jensen, 2008). Urban satellite remote sensing is very important and definite for
demonstrating the relations between people and their environment (Li and Yeh, 1998).
Space-borne remote sensing data and satellite images are particularly beneficial for
developing countries as they are cost effective and time saving techniques where as
conventional methods of surveying are expensive and time consuming (Jensen et al.,
1995; Dong et al., 1997), and these procedures and systems of remote sensing have
become more feasible substitutes to traditional survey and methods of ground-based land
use mapping and urban analysis.
2.4. Urban Climate Patterns and Land Surface Temperature
Urban climate refers to the difference between the climatic conditions of a city
and the climate of its neighboring countryside. The most significant features of urban
climate include higher air and land surface temperatures, lower humidity and changes in
radiation balances and constrained atmospheric exchange and their cause increases of
pollutants from a variety of sources (Kuttler, 2008). Urban climate can also be referred to
specific climate conditions for a long time in cities that differ from surrounding country
sides and are attributed to urban development, urban expansion, massive change in urban
32
landscape, and variations in air and surface temperature of urban area (Eum et al., 2011).
Urban land cover changes are intensely altered landscapes aloof from ecosystems and
natural processes (Blake, 2011). Urban areas have weaker wind flow and have higher
temperatures as compared to neighboring non urbanized areas. Cloud cover, air pollution,
orientation of infrastructure and shades of the building decide the sum of sunshine
received by an urban area. Huge and tall structures in the urban areas influence the flow
of radiation (Huang et al., 2011). The absorption of solar radiation is higher in urban
areas with more thermal conductivity and similarly the capacity to store urban heat
throughout the day and release at night-time (Xian et al., 2006). Moreover, the surface
structure of urban areas possesses such features as they influence the micro-climate of
urban area (Carnahan et al., 1990; Aniello et al., 1995; Voogt and Ok, 2003; Huang et al.,
2011).
The weather elements are detected in Met stations in urban areas, at least one
station in every city. In some cases, these observations don’t detail micro climate
conditions and actual climate changeability. Even in some cities, the climate stations are
not found and, therefore, the climatic data is received from the neighboring Met station
(El-Nahryv and Rashash, 2005). So, the remote sensing thermal infrared images are
widely used for estimation of climatic condition because of their capacity to cover larger
areas providing thermal condition of cities and surrounding areas. Satellite remote sensing
imagery with thermal infrared data are distinctive bases of information to describe urban
climate and also utilized for the estimation of land surface temperature (Weng, 2009).
Typically urban surfaces display higher overall surface and air temperatures than
vegetation covers and rural areas because urban land constructions trap more heat in the
urban canopy layer while vegetation cover helps to moderate the surface temperatures of
the adjacent non urbanized areas (EPA, 2003). The relationship of different types of land
use can be associated with land surface temperatures (Pease et al., 1976), Temporal and
spatial change in LULC can be observed with changes in urban heat island intensity and
magnitudes (Lo et al., 1997), and seasonal investigation can also be analyzed through
seasonal LULCC patterns (Liu et al., 2008). Land use changes are an imperative input to
global climatic variation and environmental monitoring (USCCSP, 2003). The population
growth and anthropogenic activities have been renowned as the leading reasons behind
land use land cover change, although similar changes do arise gradually and naturally
33
(Coppin et al., 2004; Nagendra, 2004). Human beings put pressure on the land, altering
its land cover type, in order to maximize their benefits from the land.
Lambin et al., (2001) investigated the factors of the land use and land cover
change which in return modify many environmental development policies. He challenges
the opinions that population growth and poverty were the prime reasons for land use and
land cover change. This study reflects that the increasing economic opportunities caused
by institutional factors are the determining forces for land use. Both local and national
polices and market define constraints and opportunities for new land uses. Global forces
have assumed a decisive role in land use change for they invigorate or mitigate local
factors. They considered that the human influence on land cover included: demographic,
cultural, socio-economic, urbanization, technological, institutional or related to
globalization. The environmental effects of Land use land cover change can be
categorized into: climate change, environmental pollution, biodiversity change, LST
change and other impacts (Ellis and Pontius, 2009). For example: converting forest and
vegetation cover to impervious surfaces and other land uses can lead to deforestation to
biodiversity loss, overgrazing to pollution, climate change and higher temperature in
cities. Environmental and climatic changes affect civilization (Sherbinin, 2002), so
evidence on land use conversion can always support decision and policy making (Adu-
Poko, 2012).
Natural disasters and anthropogenic activities are the main reasons for dramatic
changes in land use profile (Muttitanon and Tripathi, 2005). Land use profile
transformations affect global climatic and environmental sustainability on a local,
regional and global scale, which makes the examination of these LULC changes vital for
future well-being of the mankind (Sun et al., 2012). Some types of LULC changes,
which origin from direct conversion in land use and its impact on micro-climate and air
temperature, meteorologically are very important (Owen et al., 1998). The main threat to
the environment and humanity originates from anthropogenic (i.e., human-induced)
modifications rather than from changes forced by nature. The most prominent
consequences of anthropogenic activities are such changes in land cover as vegetated
cover, forests lands turning to impervious surfaces and urban land uses (Tan et al., 2010).
One of the greatest significant types of Land use transformation is urbanization and urban
expansion itself (Xian et al., 2006; Zhou et al., 2011). In relationships of surface
34
temperature change, conversion from vegetation cover to impervious surface can have
similar consequence as global warming and globalization (Mohan et al., 2011).
There is an overall compromise that urban expansion and development lead to
land surface and atmospheric modification, land use alterations as well as the content and
structure of the atmosphere (Roth et al., 1998). Altogether, these alterations consequence
in appearance of several micro and meso-scale change of urban climate, warmer than the
surrounding of rural areas (Zhou et al., 2011). Urban heat islands phenomena basically
describes the urbanization impact on urban climate at local, regional and global level.
Urban heat island shows the inconsistency in ambient temperature inside an urban area
and its immediate country side (Nonomura et al., 2008) and demonstrations of the result
of cities, storing and generating more heat than the neighboring country sides (Aniello et
al., 1995).
The magnitude of earth surface temperature increase is closely associated with the
extent and type of urban development rather than the actual size of urbanized area or
population (Roth et al., 1998; Xian et al., 2006). It means that the mega-cities of the
developing countries might experience higher temperature effects due to UHI as
compared to the older and bigger cities in the developed countries (Weng, 2009). Rapid
growing urban surfaces display different thermal, radiative, aerodynamic, diverging
thermal and moisture properties than rural surfaces (Xian et al., 2006). Owing to the
reduction in agricultural land and surface moisture, the temperature is dramatically
increasing in urban area with continuing urbanization activities (Owen et al., 1998).
There is also a conflicting urban climate effect known as urban heat sink along
with the phenomenon of UHI. Urban heat sink demonstrates an opposite stance to UHI of
asserting urban places cooler than the rural areas in the surroundings. Although the
phenomenon of UHS is even more time dependent than UHI, yet, it can be easily
influenced by morphological and seasonal factors. For instance, the radiant and spectral
characteristics of pre-emergent state of crops are identical with the bare soil, and they
exercise remarkable impact on overall land surface temperature. Moisture and density are
also major factors attributing to the abnormal surface temperature of land (Carnahan et
al., 1990).
35
Huang et al., (2011) estimated that the increasing distance from the downtown
tends to decrease the urban temperature. Urban heat island is higher in land surface
temperature than the non-urbanized surrounding areas including some hot-spots within
the area with higher temperature. Some of the other researchers conducted studies and
concluded that higher temperature is connected with less vegetation and land use land
cover changes such as industrial and commercial zones with large open pavements,
parking lots and flat roofs and not with the distance dichotomy of downtown. Weng,
(2009); Roth et al., (1998) and Zhou et al., (2011) emphasize that increase in vegetation
cover contributes to decrease UHI influence along with the growth in water bodies.
Urban land use has a substantial influence on global, regional, and local, climate
and environmental alteration, and has momentous social, economic, biophysical,
ecological, and climatic special effects (DeFries et al., 2010). These impacts are
augmented by the Spatio-temporal variation of urban land use alterations and they tend to
last for decades and are frequently irreversible (Seto and Shepherd, 2009). Optical
satellite sensors on board several remote platforms show an important part in the urban
expansion monitoring and its impact on LST. The creation of remote sensing satellite
equipment is through it conceivable to retrieve land surface temperature for local region
and global scales through different airborne sensors and satellite platforms that detect and
capture thermal infrared data from Earth’s surface (Streutker, 2002).
The thermal environmental condition in cities is characterized by the urban heat
island phenomena affecting human health, climate, environmental conditions and energy
balance. Ground-based fix Met station observations reflect only thermal condition around
the Met station. On the other hand, utilizing satellite remote sensing, thermal infrared
bands allow the investigator to get the thermal climatic condition for each and every pixel
in the satellite thermal image. Remote sensing is a convenient tool and technique for
studying the environment through satellites sensor systems recorded digital information
for energy patterns and balance (Weng et al., 2004). Now-a-days, thermal infrared urban
imagery has been extensively utilized to measure land surface temperature in urban areas
and appraise the urban heat island phenomenon (El-Nahry and Rashash, 2005; Raja sekar,
and Weng, 2009).
For the evaluation of the LST accurately, various atmospheric measurements are
required simultaneously over the area of study. The climatological analysis requires a
36
network of in situ measurement to provide historical data of atmospheric temperature
with moist static energy trends. Despite the availability of the in situ data, the spatial
resolution of the network is not efficient enough to identify the areas of increased emitted
surface heat, according to the measurements obtained by the monitoring stations. In
addition, in situ measurements are not efficient enough to provide indication of thermal
properties, discarding surface features because of the height of the air temperature
measurements. However, airborne or satellite sensors can measure the radiant emissions
from the surfaces and such larger observations enable the measurement of thermal
properties of small surface features. It also allows investigation of high spatial resolution
of urban microclimates (Hardegree, 2006).
2.5. Use of Remotely Sensed Data in Land Surface Temperature
Estimation
Earth Surface Temperature (EST), containing land surface temperature and Water
Surface Temperature (WST), mentions the temperature of the highly significant layer
where the surface and atmosphere converge (Maimaitiyiming et al., 2014; Yang et al.,
2014). Earth surface temperature is a significant parameter reflecting the environment of
the earth surface, and is most commonly utilized in numerous fields of studies such as
global warming (Friedel, 2012), agricultural monitoring (Son et al., 2012), the effects of
UHI and climate change.
Land surface temperature, is frequently referred to as the skin surface hotness of
the Earth and as retrieved from Satellite remotely sensed thermal infrared images
(Trenberth, 1992; Anderson et al., 2011). Land surface temperature tends to feel the heat
of the surface at a specific location. From a satellite remote sensing stance, the surface
means everything is detected by sensor over the ground. It might be the grass on a lawn or
the leaves in the canopy of a forest, snow and ice and the roof of a building. Thus, LST is
not the similar as the air temperature that is encompassed in the daily weather report of
fixed station (NASA, 2000; Seba, 2013).
Land surface temperature is an essential element in evaluating and exhibiting the
surface energy and water balance, evapotranspiration (ET) and surface moisture (Gillies,
Carlson, Cui, Kustas, and Humes, 1997; Moran, 2004; Carlson, 2007), and climate
change at local, regional and global scale (Jin, Dickinson, and Zhang, 2005; Weng, 2009;
37
Rozenstein et al., 2014), with principal significance for multi-dimensional applications,
like urban climate, vegetation monitoring and the hydrological cycle (Ramanathan et al.,
2001; Kalnay et al., 2003; Wan et al., 2004; Chapin et al., 2005). Land surface
temperature and its spatial differences have long been emphasized of research on the
phenomenon of Surface Urban Heat Island (SUHI) (Oke, 1982; Streutker, 2003;
Rajasekar, 2009; Imhoff et al., 2010). Land surface temperature variations in time and
space, observed by remote sensing techniques and thermal images are utilized for the
estimation of a magnitude of geophysical variables, such as vegetation water stress, soil
moisture, evapotranspiration, and thermal inertia (Agam et al., 2008; Kustas and
Anderson, 2009; Karnieli et al., 2010).
LST is the key factor determining the energy exchange and surface radiation
(Weng, 2009), monitoring the distribution of heat flow between the temperature of
atmosphere and land surface (Tan et al., 2010). LST, as a significant variable, aids in
governing radiative, sensible and latent heat changes at the boundary of biosphere and
atmosphere (Guillevic et al., 2012). Thus, monitoring and understanding the dynamics of
the LST and relationship with anthropogenic activities are critical for demonstrating
environmental changes (Kerr et al., 2004), forecasting climate and monitoring vegetation
(Meng et al., 2009). For example, models with climate simulations display that a major
reduction in agricultural land and vegetation, has foremost to a rise of land surface
temperature (Shukla and Mintz, 1982), a drop of evapotranspiration (Collatz et al., 2000)
and rainfall over surfaces of land and altering the balances of sensible and latent heat
changes (Moran et al., 2009). Consequently, Land surface temperature is a significant
component of the climatic change that can be retrieved from optical satellite remote
sensing explanations to observer long term ecological and climatic changes (Guillevic et
al., 2002; Guillevic and Koster, 2002).
Land surface temperature works as a vital indicator of biological, chemical, and
physical processes of the ecosystem. Land surface temperature is influenced by such
properties of urban surface roughness, surfaces as color, chemical composition and
humidity (Tan et al., 2010). LST controls the atmosphere especially lower layers. Thus, it
can be critical factor for the urban environment and also called weather variable because
Land surface temperature modifies the balance of energy and surface radiation (Retalis et
38
al., 2010). Land use arrangement is one of the major factors manipulating LST,
particularly the percentage of each land use type occupying the urban land.
Urban built-up land and buildings can have a particularly high impact on LST
(Zhou et al., 2011). LST has a positive relationship with built-up structure and shows
negative association with vegetated grounds and forests cover (Sun et al., 2010). Major
reduction in agricultural land influences the balances of energy and heat exchange,
leading to an intensification of LST, at the same time, evapotranspiration and
precipitation have the reverse trend (Guillevic et al., 2002; Meng et al., 2009; Zhou et al.,
2011). Not only the high density areas, but buildings and their feature structures also
matter and open surfaces, paved areas of complicated shapes tend to increase land surface
temperatures.
Figure 2.2: The Albedo of different Land Surfaces
Source: Oke, 1987
The traditional method of getting land surface temperature was measurement by
navigates with thermometer riding on ground vehicles and observations obtained from
fixed ground based Met station (Voogt and Oke, 2003; Srivant et al., 2012). Due to the
variation of LST, the traditional technique of discrete point observations taken from fixed
station cannot be obtained continuously and large-scale information about the land
surface temperature (Yang et al., 2014). However, the practicability of satellite remote
39
sensing and thermal infrared technology makes it possible to estimate the land surface
temperature spreading over outsized areas with a systematic re-examine competence
(Peng et al., 2014).
Table 2.1. Radiative Properties of Several Materials Material Albedo (α) Emissivity
Asphalt 0.05 – 0.20 0.95
Concrete 0.10 – 0.35 0.71 – 0.91
Urban areas 0.10 – 0.27 0.85 – 0.96
Soils: wet to dry 0.05 – 0.40 0.98 – 0.90
Grass: long to short 0.16 – 0.26 0.90 – 0.95
Source: Oke, 1987
Remote observation of LST became possible by aircraft and satellite platforms
providing new horizons for the observation (Roy et al., 2010), of land surface
temperature, and the critical evaluation of their relationship using the thermal remote
sensing and urban climatology simultaneously (Voogt and Oke, 2003), and to make
digital classification of land use cover as input to study energy exchange between surface
and atmosphere through models (Srivanit et al., 2012). Voogt and Oke, (2003) proposed
03 key uses of satellite remote sensing thermal images to the learning climate of urban
areas. Two of them focused on investigating relationships either between urban spatial
structure, land surface characteristics and thermal designs and or between surface and
atmospheric islands of heat and the third is addressed on reviewing surface energy
exchange stabilities by joining models of urban climate with thermal remote sensing data
(Srivanit et al., 2012).
Since 1980s, many studies have been accompanied to investigate the viability and
precision of thermal image analysis and uses for land surface temperature retrieval (Li et
al., 2013). Since the availability of satellite TIRs data (Vinnikov et al., 2011), many
studies have been utilizing satellite images to monitor land use changes and their impacts
on Land surface temperature (Weng, 2001; Dousset et al., 2003; Xiao et al., 2007). A
range of different algorithms, such as multi-channel, split-window and mono-window
algorithm (Katsiabani et al., 2009; Qin et al., 2001a; Zhou et al., 2010) were
recommended to estimate land surface temperature for actual application situations and
account of the individualities of dissimilar type of data. Thermal infrared data is measured
40
by remote sensing satellite sensors in thermal infrared spectral range. Radiance of the top
of the atmosphere detected by satellites thermal infrared sensors (Kustas and Anderson,
2009; Weng, 2009). However, radiation measured by the satellite sensor is influenced by
atmospheric constituents and in order to get accurate values, this original thermal data
must be modified for atmospheric and emissivity effects (Weng et al., 2004). This
radiometrically corrected thermal infrared imagery can be utilized to estimate LST in
Kelvin or degree Celsius (Weng, 2009; Vinnikov et al., 2011).
Historical observations of urban climate through ground based station
measurements were carried out by using regular meteorological networks. In-situ
instruments measure the chemical or physical properties of the adjacent air. Platforms
utilized for atmospheric and surface observations involve ships, ground-based stations,
weather balloons, and aircraft and satellite sensors. Satellite remote sensing systems
indirectly retrieve these properties from perturbations of electromagnetic signals passing
through the air (Jensen, 2007). In recent decades, airborne and satellite sensors, such as
Landsat TM, ETM+. OLI_TIRs, MODIS, ASTER and HCMM (Sobrino et al., 2004;
Hung et al. 2006; Pu et al., 2006; Nichol et al., 2009) and AVHRR (Advanced Very High
Resolution Radiometer) (Kato and Yamaguchi, 2007) images have been utilized in
studies correlated to the land surface temperature features of urban places (Dousset and
Gourmelon, 2003; Ji and Peters, 2004; Pongracz et al., 2006; Sahin et al., 2012).
With the growing recognition of the significance of LST, procedures and
techniques for its estimation from satellite images have continuously been developed (Li.,
2013). In addition to land surface temperature quantities, this thermal infrared imagery
might also be used to get emissivity data of dissimilar land surfaces with various temporal
and spatial resolutions and precisions. Land surface temperature and emissivity data have
been used in environmental and urban climate studies (Quattrochi and Luvall, 1999),
mostly for examining patterns of LST and their association with land surface
physiognomies, evaluating UHI, and relating land surface temperatures with energy
fluxes of land surface for depicting landscape processes, patterns and properties (Weng et
al., 2004).
Satellite remotely sensed thermal Infrared imagery data are an exclusive basis of
info to describe heat islands, which are interrelated to the heat islands of canopy layer.
Atmospheric temperature data particularly, everlasting MET station temperature data
41
offer long term temporal coverage but there is lack of spatial coverage. Measurements
and observations by ground vehicles rectify inadequacy to certain degree but fail to
provide a synchronized image of the whole urban area (Weng, 2009; Weng and Fu,
2014). Only thermal infrared imagery data can offer a simultaneous and continuous
observation of an entire city, which is of major significance for comprehensive study of
urban land surface temperature (Schmugge et al., 1998; Schwarz et al., 2011).
Thermal infrared satellites data has lots of advantages, due to this most of the
urban climate studies preferably utilized thermal data. For instance, satellite remotely
sensed data permits for the acquisition of thermal data over a region and very large areas
and also provides a lot of information; on the other hand direct measurements only deliver
points measurements. Another significant advantage of satellite remotely sensed data is
that it is very cheap and generally easy in acquiring thermal data, while direct
measurement method is tremendously expensive and time consuming for the assessment
of whole of the region and area of interest. It is also essentially, that the thermal data from
the satellite sensor cover is of the whole of the region and area of interest at one time.
On the other hand, the direct measurements of the temperature were acquired from
the MET stations at different times, at different conditions, which affect the analysis and
inferences. Such measurements are also coupled with some advantages including ability
to take the vertical surface into account, which is particularly important for highly dense
urban built-up areas. Satellite remotely sensed data has some flaws like its sensitivity to
atmospheric conditions, which depends upon surface roughness and land use type, lack of
information about vertical magnitude of land surface temperature. Despite these
weaknesses, satellite remotely sensed data remains one of the most reliable and important
sources of thermal data for urban heat island and climatic change studies.
2.6. Relationship between NDVI, NDBI and LST
In order to examine the relationship between Land surface temperatures and land
use changes (e.g. vegetation and built-up area), many researchers employed a quantitative
method in the discovery of the correlation between temperature and numerous remote
sensing indices used. For the extraction of various land surface features from satellite
remote sensing images, a variety of indices has been developed (Chen et al., 2006).
Qualitative approach on the association between the land use pattern and land surface
42
temperature helped us in urban planning and decision making (Tian & Xiangjun, 1998). It
is acknowledged that several vegetation indices acquired from satellite remote sensing
imagery can be utilized in the extraction of vegetation quantitatively and qualitatively.
Several remote sensing indices have been quantitatively utilized to characterize
land use land cover categorized for land surface temperatures studies (Liu and Zhang,
2011). On the other Qualitative researches on the correlation between LST and LULC,
patterns were utilized for sustainable development and planning of urban land use (Xu,
2010). Several indices of vegetation got from satellites thermal imagery can be utilized in
the assessment and amount of vegetation both quantitatively and qualitatively. The NDVI
(normalized difference vegetation index) is the most frequently utilized method for the
assessment of vegetation cover (Tian and Xiangjun, 1998).
Other several indices comprise the normalized difference built-up index, the
normalized difference Bareness Index (NDBaI), normalized difference water index
(NDWI), Vegetation Water Content (VWC), (Gao, 1996), Normalized Difference Snow
Index (NDSI), used for built-up land, vacant land, water bodies and snow cover
extraction, respectively (Bannari et al., 1995; Hall et al., 1995; Mcfeeters, 1996; Zha et
al., 2003). The calculations observed through these indices are founded on several stuffs
like multispectral satellite image bands reflection or in terms of strong absorption (Jensen,
2006).
The estimate of vegetation productivity Soil Adjusted Vegetation Index has been
utilized (Yuan and Bauer, 2007) in heterogeneous urban areas (Weng et al., 2004). Zha et
al., (2003) recommended the usage of a Normalized Difference Built-Up Index reliant on
the spectral reflectance attribute of artificial exteriors. Xu, (2007) suggested the Index
Based Built-up Index (IBI) for the quick documentation of built-up structures from
satellite imagery. The Normalized Difference Water Index is applied to illustrate water
content quantitatively (Huete, 1988). It is imaginable that the application of NDWI, IBI,
NDVI, and SAVI could characterize land use categories through quantitative methods for
recognition of correlation between dissimilar indices like NDVI, SAVI, IBI, NDWI and
LST in urban heat island and climate studies (Xu, 2007; Zha et al., 2003).
The investigation of the spectral signature of the area under study supplements the
development of index for its extraction of information from the satellite images (Gitelson
43
and Merzlyak, 1996; Huete and Jackson, 1987; Dozier, 1989). Satellite remote sensing
images are accomplished of measuring, estimating and detecting a range of components
concerning the morphology of town and cities (Webster, 1995), such as the, shape,
amount, textural form, density and expansion of built-up land and decreasing vegetation
cover in urban areas (Mesev et al., 1995). Satellite remote sensing images are particularly
significant in urban regions of prompt land use land cover changes someplace the updates
in terms of information are tiresome and laborious through conventional surveying (Fung
and LeDrew, 1987; Martin, 1989). The observing of urban expansion and development is
mostly to govern the amount, variety and site of land use conversion (Howarth, 1986;
Eastman and Fulk, 1993).
Several research projects have addressed the appropriate use of satellite remote
sensing images in a comprehensive range of analysis and urban applications for
supporting decision and policy making environment (Gatrell and Jensen, 2008; Zeilhofer
and Topanotti, 2008;). In the areas of urban land use planning, several studies have been
investigated through satellite images, mainly Spatio-temporal modelling of urban growth
(Jensen and Cowen, 1999; Hathout, 2002; Jat et al. 2008) and the urban change detection
analysis (Liu and Lathrop, 2002; Alphan, 2003; Herold et al., 2003a; Bahr, 2004; Jensen
and Im, 2007), land use changes appraisal (Weng, 2001; Yuan et al., 2005; Yuan, 2008)
estimation of LST and observing urban heat island Phenomena (Kato and Yamaguchi,
2005; Xiao et al., 2006).
2.7. Urban Expansion and its impact on Land Surface Temperature
The world is experiencing rapid urban expansion, where cities are accommodating
more than half of the population of the world, and furthermore, 70% of the population
over the globe will reside in the urban areas by 2050 (UNO, 2007). In the recent era, the
association between the land use type and the environmental quality has intensively
received attention for urban planning (Stone et al., 2001). Patterns of Land use reflect the
fundamental social and natural processes, and proved key information to understand and
model several phenomena on the surface of the Earth (Howarth, 1986; Liang, 2008).
More prominently, land use/land cover change data are significant for
environmental and climate change studies and developing considerate the multifaceted
relations between anthropogenic actions and global temperature change (Jung et al.,
44
2006; Gong et al., 2013). Precise land use identification is also an important aspect for
enlightening the presentation of hydrologic, atmospheric and ecosystem models and
changing land surface temperature patterns (Miller et al., 2007; Running, 2008). LULC
information is critical and helps as the foundation for worldwide change of surface
temperature and climatic studies (Bounoua et al., 2002; Jia et al., 2014).
The climate in metropolises and supplementary built-up places is transformed due
to the commercial and industrials activities of urbanization, urban expansion and changes
in Land use type. The most authoritative problem in cities is increasing land surface
temperature due to conversion and alteration of vegetated cover to impervious surfaces.
These land use changes affect the surface temperature, absorption of solar radiation,
storage of heat, evaporation rates, wind turbulence and can extremely alter the
environments of the land surface to atmosphere over the whole cities. The temperature
variance between cities and countryside areas is typically named as urban heat island
Phenomenon (Mallick et al., 2008).
When changes occur due to urban expansion over a period of time as a
consequence of conversion of vegetated surface to impervious surface and its replacement
with land surface such as commercial buildings, highways, parking lots and residential
areas and consequently modify the surface temperature and characteristics of the moisture
and albedo (Betts, 1999); Thus, changes in land use result in a consistent modification in
the land surface temperature of that area. These changes in land surface temperature tend
to increase the temperature differences between rural and urban areas. Table 2.2 shows
urban-rural constraints amplifying the urban heat island effect (Robinson et al., 1986;
Harwood, 2008).
45
Table 2.2: Urban-Rural Contrasts
Elements Parameter Urban Compared with Rural
(- less; + more)
Incoming
Radiation
On Horizontal Surface
Ultraviolet
-15%
-30% (winter)
-5% (Summer)
Temperature Annual Mean
Winter Maximum
Length of freeze free season
+0.7 °C
+1.5 °C
+ 2 to 3 weeks
Wind Speed Annual Mean
Extreme Gusts
Frequency of Calms
-20 to -30%
-10 to -20%
+5 to +20%
Relative Humidity Annual Mean
Seasonal Mean
-6%
-2% (Winter)
-8% (Summer)
Cloudiness Cloud Frequency and Amount
Fogs
+5 to +10%
+100% (Winter)
+30% (Summer)
Precipitation Amounts
Days (with <5mm)
Snow Days
+5 to +10%
+10%
-14%
Source: Harwood, 2008
Voogt and Oke, (1998) explored the variations in surface temperature rise owing
to the patterns of shaded and irradiated surfaces. A strong anisotropy is also exhibited in
light industrial and residential land uses. Similarly, Ao and Ngo, (2000) investigated land
surface temperature by means of GIS and field measurement in Vancouver, Canada. The
study aims at finding out the association between the land use type and surface
temperature within the urban areas of Vancouver. The research quantifies the influence of
vegetation, density of the built environment and infrastructure and impervious surfaces,
on the release of heat. The research propagates that the zones with higher population
density such as center core, have higher temperature interconnected to the thermal
material goods of existing infrastructure and street physiognomy. The coolest temperature
was noted near the dense vegetation. Ifatimehin and Ufuah, (2006) also incorporated the
46
study by utilizing GIS and RS methods combined with field checks and survey to map
land use changes and measured the rate of urban expansion along with the loss of
vegetation in Lokoja between 1987 and 2005.
The built-up area, vacant land, cultivated land and other land use types increase at
the expense of vegetation cover. Urban expansion has also led to environmental and
ecological problems such as increase in surface temperature, erosion and major reduction
in vegetation cover. He et al., (2006) demonstrated a newly found urban expansion
scenario patterns through integration of two different models namely System Dynamics
(SD)-based model and Cellular Automata (CA)-based model. One model was applied in
Beijing to study the urban growth from 1991 to 2004 and on its basis future urban growth
was predicted for 2020. Several studies such as Kalnay and Cai, (2003); Trenberth,
(2004); Feddema et al., (2005); Christy et al., (2006); Mahmood et al., (2006) and Ezber
et al., (2007) examined and proved that if land use changed, there was a corresponding
change in land surface temperature in urban areas (Chase et al., 2000).
Yue and Xu, (2008) observed that major factors affecting urban environment of
Shanghai were population density, vertical development of buildings, types of underlying
surfaces and allocation of industries. Satellite remotely sensed data have been utilized to
investigate the relationship between land surface temperature and different land use land
cover categories such as vegetation and artificial surfaces (Xian and Crane, 2005; Van
Thi and Xuan Bao, 2010; Xu et al., 2010). Remotely sensed thermal images that retrieve
land surface temperature have been efficiently utilized to determine the effects of land use
changes on thermal urban environment (Sun et al., 2010). Several classification
approaches such as the maximum likelihood (Weng et al., 2004; Basar, 2008), spectral
un-mixing and iterative self-organizing method (ISODATA) have been utilized to derive
land use types and to describe the statistical correlation between the urban features and
urban thermal environment (Weng et al., 2014).
Thermal remote sensing, however, has some deficiencies. It often overestimates
the intensity of the urban heat islands, owing to the urban surfaces, heterogeneous in
nature, as detected by the thermal sensors of satellite (Roth et al., 1989a). Voogt and Oke
(1997) investigated this issue by making comparison between in situ measurements of the
temperature with the surface temperature measured by thermal images. As anticipated,
the measured air temperature can considerably differ from land surface temperature as
47
estimated by the satellite thermal images. The precision of the measurements is
determined by the resolution of the sensors.
2.8. Urban Heat Island
Temperature in urban areas is typically warmer than surrounding countryside; this
unique phenomenon is recognized as the Urban Heat Island (UHI) (Landsberg, 1981;
Moreno-Garcia, 1994). There is a measureable pocket of warm air produced by
metropolitan cities as they represent areas where human activity is concentrated and large
density of population live and work. Urban heat island effects encompass some former
observations in climatology, starting from the works of meteorologist Sir Luke Howard in
early nineteenth century (Howard, 1818). The phenomenon of UHI was first observed in
London in 1820, Sir Luke Howard documented that temperatures in London was
remarkably warmer (night was 2.1°C) than the rural areas (Harwood, 2008). The USA
started its research on urban climate in the mid-1950s, but serious urban climate
monitoring did not begin till the early 1970s (Gabler et al., 2009)
A number of factors mandate that the temperatures of urban area are normally 1-
6°C (2-10°F) warmer and varied from those of the surrounding countryside. Several
factors include; energy use, industry, automobiles, human population, materials and
buildings, pollution levels and water on the surface. As urban development increases and
global population grows, the above mentioned factors will intensify too, and UHI will
directly affect more people than the climatology of the region in general (Gabler et al.,
2009). The intensity and formation of UHI depend on climatic conditions and impervious
surfaces in cities. The difference between urban and rural temperature exists, especially
during clear, calm conditions and is the smallest with windy conditions. It is generally the
largest spatial extent of UHI in evening time (Kidder and Essenwanger, 1995).
UHI is one of the major effects of urban expansion that eventually leads to certain
changes in surface temperature, water vapors, solar radiation absorption, air temperature,
and evapotranspiration and air pollutant. All these changes directly affect human health in
general. The phenomenon of urban heat island is also referred to as higher radiation heat
budget and thermal conductivity (Tan et al., 2010) in urban areas because of impervious
surfaces when compared with the countryside (Landsberg 1981). Anthropogenic activities
contributing to the urban heat island effect include installation of new units for industrial
48
activities, increasing number of vehicles, cooling and heating systems in residential areas
and commercial centers and economic activities for material gains in the urban centers
(EPA, 2003). The IPCC, (2007) reports that a considerable increase is observed in
quantity of methane, carbon dioxide and nitrous oxide in the air, caused by anthropogenic
activities. Cities are prime contributors of greenhouse gases in this regard (Parry et al.,
2007). The effect urban heat island is observed in the spatial distribution of higher land
surface temperature affected by urban expansion which is maintained by surface heat
fluxes. Land surface temperatures are measured as primary source for conducting urban
heat island studies.
The most discussed impact of urbanization is an increase in local and regional
temperatures. Specifically, on a micro-scale, urban heat island is the most important
phenomenon in climatic change (Stohlgren et al., 1998). There is thermal anomaly in the
heat islands, differentiating the observation of temperature from one location with the
other; for instance, the temperatures of the urban areas are higher than those of the rural
areas (Weng, 2002; Weng et al., 2004). UHIs vary in their severity among seasons and
scale (Pinho et al., 2000). Several factors including, population and city area, the size of
green spaces, geographical location and climatic conditions can affect the intensity of
urban heat islands (Kalnay et al., 2003; Kim et al., 2005).
Figure 2.3: Temperature profile of the urban “heat island” shows the increase in
temperature with increase in urbanization
Source: Gabler et al., 2009
49
Under proper conditions, as Oke (1982) puts in, urban heat island can range up to
10-15°C. As a consequence of micro climatic change, as created by the urban heat island,
the necessity increases in energy consumed for cooling systems in the buildings (Adina et
al., 2009). Akbari et al., (2001) asserts that increase in 1°C temperature raises demand for
electricity from 2 to 4 % every year. Vegetation in the typical urban built up areas is
lesser than the surroundings and the surfaces are usually in dark contrasts as compared to
the rural areas. The difference in the temperature of an urban center with its surroundings
comprising of rural areas reaches up to 2.5°C, at daytime in warm summer, causing
additional demand for about 5-10% electricity (Akbari et al., 2001).
According to Oke (1987), Akbari et al., (2001) and Santamouris et al., (2007), the
causes of urban heat island include hindrance in the flow of air because of high
architectural structures of the buildings, release of heat generated by anthropogenic
activities, absorption of solar radiation because of low albedo and low amount of
evapotranspiration as there is less vegetal cover. Figure 2.4 summarizes the causes of
UHI:
Figure 2.4: Causes of Increase of Urban Temperature and UHI Formation
Source: Nuruzzaman, 2015
Urban heat island is created due to a number of factors which contribute to
increase in land surface temperature, including low albedo materials (Bouyer et al.,
2009), human gathering, increased use of air conditioner (Okwen, 2011), destruction of
trees (Akbari et al., 2001), urban canopy (Masson, 2006), wind blocking (Priyadarsini,
50
2008) and air pollutants (Bousse, 2009). The effects cause discomfort to the residents of
the city center as they are devastating, specifically in arid and tropical regions in summer
time (Akbari et al., 2001). Improper planning of the cities is one of the reasons
contributing to intensity of urban heat island effect (Li, K. et al., 2012). Taha, (1997)
emphasizes that the intensity of urban heat island is added by the air pollutants realized
from power plants, industrial processes and exhaust gases omitted from vehicles along
with the anthropogenic activities generating heat. Urbanization is accelerating more than
half of total population on the planet, living in urban territories in 2008. This number is
projected to be increased up to 66% by 2050 (Zhou et al., 2016).
Figure 2.5: Effect of Urban Heat Island formation
Source: Nuruzzaman, 2015
The characteristics of urban heat island effect have been extensively studied in the
present research. Deosthali, (2000) claims that both heat and moisture are observed in the
heart of the city at night, whereas the day time is dry and hot island as the sun rises. The
maximum urban heat island is observed to be average in summer, while in winter, it is
strong (Kim and Baik, 2002; Zhong, 1996). The intensity of urban heat island was observed
to be correlated with the temperature of the country side; whereas the spatial extent was
identified to be independent of both temperature of the country side and heat island
magnitude (Streutker, 2002). Giridharan et al., (2004) conducted study in Hong Kong,
and observed daytime urban heat island effect in the high-density and high-rise residential
developments. He indicated that the architectural designs of the impervious structures can
consume less energy by maximizing cross ventilation, manipulating surface albedo, total
height of the building with sky view factor. Saaroni et al., (2000) materialized a new
method for monitoring urban heat island effect on different scales and from different
51
levels. It also enabled diverse thermal coverage characteristics and spatial assessment of
surface urban heat island effect in the cities.
Nieuwolt, in 1966, investigated LST and UHI of Singapore comparing airport area
(represented as rural area) with city area. The difference recorded was reported to be
3.5°C. It was investigated that the temperature difference was an offshoot of greater solar
radiation absorption and reduction in evapotranspiration in the urban areas (Nieuwolt,
1966). Chandler, (1960; 1965) observed that the mosaic of land surfaces influence
indirectly effects on urban heat island as the local airflow patterns are changed along with
a reduced diffusion of heat from courtyards, paved surfaces and waste heat omitted from
the industrial and anthropogenic activities. The similar complexity and heterogeneity of
pattern, composition and spatial extent of mosaic of land surfaces in the cities have also
been indicated to be contributing towards the local urban heat island effects in London
(Clarke and Peterson, 1972), Germany (Blankenstein and Kuttler, 2004), Hokkaido, Japan
(Shudo et al., 1997) and Hong Kong (Giridharan, 2004).
Rao, (1972) observed surface urban heat island through satellite-based sensors for
the first time. Since his usage, a variety of satellite sensor based combinations including
aircraft and ground based have been in use to observe surface urban heat island effect
over a range of different scales. Roth et al., (1989) observed the spatial distribution of
LST along the western coast of North America in several cities. It was observed that the
patterns of daytime intra urban thermal were significantly correlated with land use. On the
other hand, at night time, urban heat island effect was not much correlated with land use.
Akbari et al., (1992) considering the previous researches conducted, concluded
that the temperature is reduced by 0.5–5°C through urban parks and large number of
trees. Nichol, (1994) utilized satellite remote sensing techniques to investigate the LST in
Singapore and thermal images analysis showed that there was a difference of
approximately 4°C between the urban and rural areas temperatures. UHI observation in
Singapore demonstrated that the vertical building structures in the locality had changed
the urban climate of Singapore. Roth et al., (2000) mentioned in their research that UHI
was a result of land surface and atmospheric modification of climate due to urban
expansion, which could lead to severe social, economic and environmental consequences.
Likewise, the impact of urbanization on land surface temperature has been observed in
many cities of the world, and temperature is increasing day by day, as well as significant
52
variation between city and countryside temperatures has been noted (Nonomura et al.,
2009).
Progress in the field of Urban Heat Island detection still has issues to be resolved.
First of all, there is lack of latest technology in satellite imagery to obtain imagery at
night time (Nichol, 2005). After the sunset, most of the heat islands have highest
intensities, but owing to the inability of obtaining satellite imagery at the night time, it
becomes difficult to obtain data of study areas for complete urban heat island analysis.
Nichol, (2005) claims that urban heat island phenomenon is chiefly associated with night
time, but the analysis remains incomplete due to the lack of adequate temporal coverage
of study areas at nighttime. Secondly, the satellite sensors with high spatial resolution are
unable to record high temporal repeat times, necessary for cloud-free images from time
period of the study area (Harwood, 2008). Thirdly, some of the satellite sensors like
MODIS or NOAA-AVHRR, with high repeat times, lack the ability of spatial resolution
and fail in microclimate analysis. ASTER data was also acquired, for the point at which
urban heat island is magnified, close to the thermal crossover time, but again the
nighttime imagery did not support the predicted magnified UHI effect (Nichol, 2005).
Chen et al., (2006) explored the correlation between several indices and
temperature in the Pearl River Delta, situated in Guandong Province of south China. They
explored that the correlation is negative when NDVI is lower, while it is positive between
the LST and NDBI. They attributed the change in the temperature trends to the increasing
built up areas and loss in vegetal cover in the study area. Jusuf et al., (2007) investigated
urban heat island in Singapore and explored the impact of land use land cover types. It
was observed that the land surface temperature is decreased at day time in the following
order; Industrial areas, commercial centers, airports, residential areas and parks.
However, the order is reversed at the nighttime, it follows as; commercial centers,
residential areas, parks, industrial areas and airports.
Kottmeier et al., (2007) studied the impact of small-scale land use on LST. They
used block-related data and airborne surface thermometry of Berlin in 1998, during Berlin
Ozone Experiment. There was a positive correlation between the LST and the sealed
surfaces within blocks. Katpatal et al., (2008) investigated the LST patterns of Nagpur,
India. They observed the impact of Land use of urban areas on atmospheric temperature
and concluded the presence of impervious surfaces in the city that formulates the heat
53
surfaces and create a canopy layer heat island. Liang and Weng, (2008) conducted a
multiple scale analysis of urban heat island in Indianapolis USA. They observed a
positive correlation between the urban landscape parameters and land surface
temperatures. Yue and Xu, (2008) observed the population density, industrial areas, urban
buildings and impervious surfaces, diversity of urban landscape and types of underlying
surfaces contributed towards the urban heat island effect in Shanghai, China and changed
the urban thermal environment. Fujibe, (2010) observed the impact of population increase
on LST in Japan on various days of the week. He concluded that diurnal variations in
LST existed on the days when people commuted in and out of the city for job. A decrease
in atmospheric temperature was observed on holidays and weekend nights. These
variations in the atmospheric temperatures are observed at larger scales in big cities.
Viterito, (1991) concludes that these variations exist at smaller scales in small cities as
same impact factors do exist there.
Rapid expansion of urban centers in Japan initiates rising awareness for urban
warming. Urban warming has been found to have contributed significantly to feel
temperature changes (Fujibe, 2011). The US EPA, differentiates surface UHIs and
atmospheric UHIs. Sun oriented energy is retained and transmitted back to the
atmosphere by the physical land structures. This is supposed to be a principal cause of
warming surface and air temperatures, particularly in the canopy layer, which is nearest to
the surface (Rinner and Hussain, 2011). Shanghai is one of the greatest and fastest
growing urban areas in China. The endless growth of resistant manufactured surfaces in
urban areas has altogether impacted the urban thermal environment; unusual urban
modifications in the city are the main supporter of the Shanghai's city and countryside
zones temperature (Chen et al., 2015).
Satellite remote sensing is a modernized, efficient and helpful tool for researchers
to monitor and conduct research on actual problems faced by modern world. The data
collected through satellite imagery are utilized for the precise and reliable estimation and
assessment of land surface temperature and global climatic changes taking place and
predictions regarding changes to come in future. Therefore, estimation of Land surface
temperature and assessing its Spatio-temporal variations are not only supportive to
comprehend ecological and environmental processes, but are also concerned with the
well-being of people.
54
CHAPTER 3: MATERIAL AND METHODS
3.1. Introduction
The title of the chapter affirms the attempt to explain data sources, methods and
techniques used while acquisition of data, image pre-processing (layer’s staking, geo-
reference, geometric and radiometric correction), image processing, Spatio-temporal
analysis, impact assessment, mapping and presentation of the data. The methods used in
this study helped in acquiring the designed objectives and in responding to the research
questions of the study. This chapter gives us Spatio-temporal analysis of change detection
and helps us to draw conclusion on the expansion of the city and its influence on surface
temperature of Lahore. The data types used for the analysis have been categorized into
two groups, satellite remote sensing data and reference data.
The present study has utilized time series of Landsat satellite imagery, Landsat 5/
Thematic Mapper (TM), Landsat 7/Enhanced Thematic Mapper plus (ETM+) and
Landsat 8/Optical Land Imager (OLI) for the years from 1973 to 2015. Satellite remote
sensing images are used increasingly for the analysis of change detection of urban
expansion and estimation of land surface temperature because it is technologically
efficient and cost effective (Epstein et al., 2002). Reference data comprises aerial
photographs, topographical maps, and land use of the study area, shape files of
administrative boundaries, in situ temperature and census data. Geographic data (GPS
points) are also collected for all the land use type. These GPS points are utilized as
training sample during the image classification and accuracy assessment.
3.2. Data and its Sources
Data used for Spatio-temporal analysis in the present study include Landsat
satellite imagery, in situ atmospheric temperature measurements, and census data. In this
research, spatial data of sequential nature of land use type and urban expansion has been
accumulated from Landsat satellite imagery, topographic sheets and along with aerial
photographs of the study area. Monitoring of urban expansion and evaluating its impact
on LST via multi-temporal, multi-source remote sensing imagery have claimed great
interest in the recent decade (Gallego, 2004; Mayunga et al., 2007). Remote sensing is,
certainly, the most effective tool in monitoring urban expansion and detecting land use
55
changes with estimation of temporal variation of land surface temperature (Foody, 2002;
Alrababah and Alhamad, 2006).
3.2.1. Primary Data
Landsat satellite imagery is the primary source of data because of its temporal
resolution and free availability. In total, six Landsat satellite images were collected for
this research. Primary data is acquired through multi-source and multi-date satellite
images from 1973 to 2015 (Figure 3.1) provided the data source for the Spatio-temporal
analysis of the study. Urban expansion and consequent change in temperature are
assessed through Landsat 5/TM, 7/ETM+ and Landsat 8/OLI_TIRs images for the year
1973, 1980 1990, 2000, 2010 and 2015 respectively. These Landsat images are acquired
and downloaded from U.S. Geological Survey database and from the site of Global Land
Cover Facility (GLCF) (glcf.umiacs.umd.edu), according to the suitability and
availability due to cloud cover (the acceptable cloud cover should not be more than 10%).
GLCF helps in understanding the environmental system appropriately providing earth
science data and its products.
3.2.1.1. Satellite Images
Urban areas are ideally analyzed by high resolution satellite images but the
availability of such images is not easy and it costs very high. The selection of accurate
satellite system and right image for urban change detection is an art we can learn with
passage of time and experience. Nevertheless, resolution, time, availability, and cost are
some of the significant constituents for its data acquisition. The present study has utilized
the times series of Landsat (5, 7 and 8) imagery at different intervals, ranging from five to
ten years since 1973 to 2015. Images of moderate resolution like satellite Landsat
imagery are accessible free of cost from the USGS in Earth Explorer website, so the
images required for different time spans were acquired and downloaded from their
official site (http://earthexplorer.usgs.gov). These images were used to determine the
urban expansion and land use changes and also estimating land surface temperature of
Lahore. Satellite images of 1973, 1980, 1990, 2000, 2010 and 2015 were required for the
urban analysis (Figure 3.1). The satellite images were opted following the criteria defined
below (Sun et al., 2008):
1. 10% cloud coverage or cloud-free over the study area satellite images should be
acquired.
56
2. The satellite images for the analysis should cover a long time span to maximize
the separability and distinguish the different land use changes and detecting
surface temperature (Tan et al., 2010).
Landsat 5, 7 and 8 data were used to carry out this research work. Landsat 5/TM
and 7/ETM+ sensor have 6 spectral bands with 1 thermal band and Landsat 7/ETM+ has
one panchromatic band with resolution 15m (Table 3.1). Landsat (5 and 7) images of
bands 1–5 and 7 have a spatial resolution of 30m (Chen et al., 2006). Landsat 5/TM,
7/ETM + imagery precisely the thermal infrared (band 6) with a spatial resolution of
120m and 60m respectively (Table 3.1) has been used for local-scale urban studies of
retrieving land surface temperature (Weng, 2002; Chen et al., 2002). Bands 1-5 and 7
were utilized for Land use type supervised image classification, while band 6 for land
surface temperature extraction in both cases Landsat 5TM and Landsat 7/ETM+ images.
Table 3.1: Metadata of Landsat (5, 7 and 8) Satellite Images
Year Sensor Bands Spatial
Resolution
Thermal
Resolution Path/Row
Date of
Acquisition
1973 MMS 1-4 60m - 160/38 23-03-1973
1980 MMS 1-4 60m - 160/38 04-03-1980
1990 TM 1-5 & 7 30m -
149/38 16-03-1990 6 - 120m
2000 ETM+
1-5 & 7 30m
149/38 19-03-2000 6.1 & 6.2 - 60m
Pan (8) 15m -
2010 TM 1-5 & 7 30 m -
149/38 07-03-2010 6 - 60m
2015 OLI
1-8 30m -
149/38 21-03-2015 Pan (9) 15m -
TIRs 10 &11 - 100m
Source: http://landsat.usgs.gov/
In the present research, Landsat 8/OLI_TIRs bands 10 and 11 are utilized to
evaluate land surface temperature with thermal resolution 100m and Landsat 8/OLI_TIRs
and spectral bands of 2, 3,4,5,6 and 7 with spatial resolution 30m and one panchromatic
band with spatial resolution of 15m (Table 3.1) are utilized to identify land use changes,
demarcating urban expansion. These spectral bands (2-7) are also utilized to generate
Normalize Difference Vegetation Index and Normalize Difference Built-up Index of the
study area (Rajeshwari and Mani, 2014). A detailed description of Landsat satellite
imagery and characters has been presented in Table 3.1. Lahore is covered in one tile
57
(Figure 3.1). Landsat (8) provides metadata of the thermal bands such as rescaling factor
value and thermal constant, which can be used for computing numerous algorithms like
LST (Rajeshwari and Mani, 2014).
The following satellite remote sensing imagery (Figure 3.1) has been used to
assess the urban expansion and estimating land surface temperature. They provide
beneficial input for mapping urban environment, monitoring urban expansion and city
planning because of their, temporal, spatial and spectral resolutions (Sadidy et al., 2009).
Figure 3.1: Imagery used for Urban Analysis
Source: http://landsat.usgs.gov/
3.2.2. Secondary Data
Dependency on secondary data has also played a vital role in the present research
work. Books, articles, annual reports and latest research papers are used as a source for
secondary data. Demographic data from the PCO also contributed to validate the results
derived from the image analysis. Secondary data are required in order to investigate the
possible relationship between the indicators of urban expansion and its impact on
temperature respectively like population growth and areal extent, increased number of
factories and increased number of vehicles per year. The source for the secondary data
required includes;
58
1. For Population Growth:
a. Census of Pakistan:
i. City Reports of Lahore,
ii. District Census reports
iii. Punjab Development Statistics
iv. Economic Survey of Pakistan.
v. Pakistan Statistical Year Book
vi. Agricultural Census of Pakistan
vii. Excise and Taxation
viii. Board of Revenue Lahore
2. For Urban Expansion;
a. Survey of Pakistan Toposheets
b. Published Maps/ Reports of Lahore Development Authority (LDA)
c. Urban Unit Lahore.
d. NESPAK Lahore
3. For Atmospheric Temperature Trends
a. Pakistan Metrological Department (PMD)
b. Thermal Landsat Imagery
4. For Vehicles
a. Excise and Taxation Department Lahore
5. For Green houses Gases
a. Environmental Protection Agency (EPA)
3.2.2.1. In-Situ Atmospheric Temperature Data
For this study ground weather stations temperature data were obtained from
Pakistan Metrological Department (PMD) for the period from 1950 to 2015. Metrological
mean monthly data of minimum and maximum temperature data was obtained from two
observatories positioned in district Lahore. One observatory is located at Shadman (PBO)
Jail Road Lahore, which is massively urbanized area having impervious surface
structures, and the second is sited as Lahore Airport (APT), which is considered to be
59
rural vicinity having rural structures (Tables 3.2 and Figure 3.2). The distance between
the two met observatories is about 10 kilometers. In order to assess the temporal trend of
air temperature of Lahore, metrological data for mean monthly average with maximum
and minimum temperature data of these two observatories were obtained for the period
1950 to 2015, and examined through simple liner regression method in which time period
is utilized as independent variable while air temperature data is utilized as dependent
variable. The data covering the time period of nearly six decades were acquired in
centigrade scale. Temperature data on monthly basis were available from these two
ground stations for the period from 1990 to 2015 and the same date satellite thermal
infrared images acquired for the purpose of retrieval land surface temperature analysis.
Table 3.2: Ground Weather Station of Lahore Weather Station Weather Data Latitude Longitude
Shadman Lahore (PBO) 1950 to 2015 31°32'34.08"N 74°19'29.16"E
Lahore Airport (APT) 1953 to 2015 31°31'13.75"N 74°24'37.93"E
Source: PMD Lahore
Figure 3.2: Meteorological Station in Lahore
Minallah, 2016 (Edited)
60
3.2.2.2. Census Data
Demographic data is utilized for examining the correlation between the
temperature and population density of the study area. Densely populated area and
industrial areas within the study area may have higher temperature owing to the
anthropogenic activities and built-up environment in Lahore. For the correlation analysis
between LST and population, data are obtained from population census organization,
Pakistan from 1951 to 1998 and Punjab Development Statistics from 2000 to 2015. The
data analyzed are temporally closest to the study’s time period.
Mostly statistical data are derived from multiple sources including all the censuses
held so for after the establishment of Pakistan, from the first conducted in 1951 and the
latest held in 1998 but as far as reliability and authenticity of demographic data is
concerned, the census of 1998 is considered the only reliable source. No doubt, this data
is not recent with reference to time scale (almost two decades old) but this is the only
latest data available in addition to population data gathered by different governmental
organizations from time to time. Likewise, socio-demographic data related to Lahore at
Union Council level is obtained from census report published by City District
Government Lahore. These secondary sources of data provided the demographic data and
information regarding to different administrating units.
3.2.2.3. Land use Data
Non-image data is one of the secondary sources of information utilized in this
research. These data have been derived from different topographical maps printed by
survey of Pakistan. A topographical map was required for the study to perform geometric
correction of satellite images from the Survey of Pakistan. Moreover, many land use maps
of Lahore i.e. 1947, 1966, 1974, 1980 and 1987 and projected land use map of 2021 have
been obtained from LDA and these maps have been utilized extensively in this research.
The most important data were acquired from Integrated Master plan of Lahore 2004
which encompasses LDA union council maps and details of Lahore land use type. In
addition, the present research is carried on GIS software which proved very helpful in the
preparation of the maps. The researcher used ArcGIS 10.1 to draw the maps. Local
boundaries of Lahore, administrative and provincial limits shape files were acquired from Urban
Unit Lahore, Lahore Development Authority and NESPAK office. Table 3.3 illustrates the
details of these data sets used for analysis.
61
Table 3.3: Data types used for the Study
Reference Data Date of Acquisition Scale Source
Topographic Maps
i. 35 L/1 & 35 L/13
Published 1957, surveyed
1925-1926 1:50,000
Survey of
Pakistan
Lahore Guide Map Published 2000,
Surveyed 1994-95 1:65,000
Survey of
Pakistan
Map of Greater Lahore 2004 - LDA
Land use Map 1966, 1980, 2004 - LDA
Analysis Zones Map 2006 - CDGL
The land use map of Lahore provides basic information regarding the numerous
aspects of urban expansion. Land use maps from Lahore Development Authority (LDA),
urban unit and NESPAK were utilized to update the data of land use modifications in
Lahore with the integration of Landsat Satellite images. Theoretical material, both
published and unpublished, from the housing and physical planning department Lahore is
utilized. It was pertinent to edit data on the basis of differences and similarities after the
collection of relevant data required. After the process of editing, different statistical
techniques were utilized to produce different maps.
3.3. Methodology
Research methodology is based on such scientific methods as are manipulated by
the researcher in a given situation for the purpose of data collection and deduction of
results from acquired facts and figures. Then researcher is able to draw some conclusions
and present recommendations for further research in that particular field. Assessing the
impact of urban expansion on land surface temperature is a complicated phenomenon
involving various activities. Likewise research involves the process of satellite images to
acquire precise, essential and exact information on the land use variation that the earth’s
surface environment is undergoing (Stemn, 2013).
The research method can be categorized into three main portions; (1) data
collection and pre-processing, (2) data processing (3) and data analysis. For the present
study the following methodology (Figure 3.3) is adopted which involves several satellite
remote sensing data processing procedures used in order to carry out this research
including; image processing, classification of the imagery, urban expansion change
62
detection analysis, retrieval of land surface temperature and calculating NDVI and NDBI
indices. The Figure 3.3 summarizes the whole methodologies that were exercised during
the execution of the present work involved in the research.
Figure 3.3: Flow Diagram of Research Methodology
Minallah, 2016
All these portions and their subparts are elaborated in the Figure 3.3 above.
Satellite imagery of different dates was processed separately, at the first step image
classification has been completed to retrieve LST and calculate NDVI and NDBI. The
results of land use classification were also utilized in order to produce land surface
63
temperature map (Figure 3.3). These steps belong to the data processing portion which
results into the making of land use type and maps of variation of land surface temperature
maps. The analysis portion comprises LST-NDVI linear Regression and Land use-LST
composite.
For the purpose of correlation study, three different data time series of MMxT,
MMiT, MAT, as well as selected urban expansion parameters i.e. number of vehicles,
population growth, number of factories and greenhouse gases for the specific area under
study are analyzed by statistical methods. A statistical test gives scholar fundamental
insight for formulating decisions quantitatively for a process or processes subsequently.
To observe the significant change in temperature trend with respect to passage of time
and for finding out its causes, linear regression and Pearson correlation were applied
respectively (Seber, 2012).
3.3.1. Image Pre-Processing
Image pre-processing is the most important part of satellite remote sensing
imagery processing and analysis, having impact on final product quality and further
processing. The aim of digital image pre-processing is to reinstate suitable image from the
distorted raw image. Image pre-processing typically consists of a series of processes
including; geometric, radiometric correction and registration of image (Lillesand et al.,
2007). To attain precise urban expansion, retrieving land surface temperature and
calculating NDVI, multi-temporal, Landsat images must be pre-processed both
radiometrically and geometrically to correct errors arising from the earth’s curvature,
imaging sensors and due to atmospheric effects (Schroeder et al., 2006). Image Pre-
processing techniques, which are sometimes termed as image rectification and restoration,
are proposed to correct sensor and platform specific radiometric and geometric distortions
found in satellite imagery
Landsat satellite images were acquired and downloaded in “GeoTIFF” image
format along with each spectral band layer in separate file. Before further images
processing, all band layers of each Landsat image were stacked in one image and the
image was thus converted into “.img” format, excluding unnecessary bands by using
ERDAS imagine 9.2. Layer stacking of different bands of each image is important
procedure for the production of a false color composite satellite image (Horning, 2009).
64
Table 3.4: Description of Landsat Imagery Spectral Resolution
Satellite Sensor Spectral Bands Spectral Range Scene
Size
Pixel
Resolution
L 5 TM multi-spectral 1,2,3,4,5,7 0.45 - 2.35 µm
185 X
185
km
30 meter
TM thermal 6 10.40 - 12.50 µm 120 meter
L 7
ETM+ multi-spectral 1,2,3,4,5,7 0.450 - 2.35 µm 30 meter
ETM+ thermal 6.1, 6.2 10.40 - 12.50 µm 60 meter
Panchromatic 8 0.50 - 0.90 µm 15 meter
L8
OLI (Coastal aerosol) 1 0.43 - 0.45 30 meter
OLI multi-spectral 2,3,4,5,6,7 0.45- 2.29 30 meter
OLI (Panchromatic) 8 0.50 - 0.68 15 meter
OLI (Cirrus) 9 1.36 - 1.38 30 meter
TIRS 10 10.60 - 11.19 100 meter
TIRS 11 11.50 - 12.51 100 meter
Source: http://landsat.usgs.gov/
The Landsat satellite images were attained as standard products, i.e.
radiometrically and geometrically rectified. With the comparison of classified Landsat
images of the study area were used to detect the urban expansion and land surface
temperature variation. For this purpose, images classification and LST retrieved were
requisite (Jensen, 2004; Bhandari, 2010). Landsat 5/TM, 7/ETM+ and 8/OLI 1-5, 7
spectral bands were utilized for LULC image classification while band 6 of TM image or
in case of Landsat 7/ETM+ 6.1 and 6.2 band and in case of land 8/TIRS band 10 and 11
band containing thermal infrared data were utilized to retrieve LST (Landsat 7 Science
Data Users Handbook, 2007).
3.3.1.1. Geometric and Radiometric Correction
Geometric correction helps to remove the geometric distortions of the raw image
data due to the perspective of the optical scheme, the motion of the sensor and terrain
factors. Geometric correction in general, re-projects the satellite image to the suitable
projection and geographic coordinate system from the sensor’s projection. Many
researchers utilize the correction level (1T & 1G) provided by United State of Geological
Survey (USGS), while other researchers accomplish their own geometric correction on
Landsat satellite images (Yang et al., 2003; Li, et al., 2011). By utilizing the United State
of Geological Survey (USGS) standardized geometric correction level (1T & 1G) offered
65
a systematic accuracy across space and time which is tough for individual researchers to
match this level (1T).
For the present research work downloaded Landsat image scenes were geo-
rectified and offered by USGS to the Standard Terrain Correction Level (1T) and no
additional geometric correction execution on Landsat imagery (Hestir, 2011) was
required. Data taken was normalized by radiometric correction at different time and
location in order to receive same pixels of spectral values. These steps are responsibility
of the company handing over the data for the user (Lillesand et al., 2007). Radiometric
correction techniques are used to remove the inconsistencies between spectral reflectance,
spectral radiation brightness of the object and pixels recorded by sensors (Jianya et al.,
2008).
In the present research, no geometric and radiometric correction was done,
because the datasets acquired from USGS were correct to some extent. Radiometric
corrections sometimes become needless with regards to change detection based on object
or feature comparison (Jianya et al., 2008). In case of Landsat 5/TM, 7/ETM+ and 8/OLI
imagery, data originates in Level 1T and Level 1G processing levels were available. This
means that Landsat image data is already with geometric and radiometric correction and
geo-referenced to UTM map projection. Digital Elevation Model (DEM) is also employed
by level 1T, to improve topographic correction (Landsat 7 Science Data Users Handbook,
2007).
3.3.1.2. Generating Subset Images
Landsat image scene had much larger extent than the study area of interest (AOI).
In order to illuminate any possible errors or to reduce file size in image classification,
original images were clipped and subset from the complete scene by utilizing the vector
layer of Lahore. Lahore is covered in only one scene (Figure 3.1). All composite false
color images were subset (Figure 3.4) into the study area of interest by using ERDAS
Imagine 9.2 (Jensen, 2004). ERDAS Image 9.2 basically provides two method of subset
image; that is by specifying the rectangular area extent and utilizing either an area of
interest tool (Bhandari, 2010). The present research work used AOI tool in order to
generate the subset images.
66
3.3.1.3. Image Enhancement
In order to increase the visual interpretation of the satellite images, which is
pertinent, all the subset images of the study area were enhanced. The image cells are
highlighted and become prominent for easy recognition and better comprehension of the
image features by using image enhancement techniques. Such techniques of image
enhancement help in identifying land use classes and selecting area of interest practically.
Figure 3.4: Spectrally Enhanced Subset Images Showing Study Area
Source: http://landsat.usgs.gov/
The histogram equalized stretch was selected to enhance the satellite images
among all the available image enhancement techniques (Shalaby and Tateishi, 2007).
Every subset image used in the research was enhanced utilizing histogram equalization
technique with the aid of ERDAS Imagine’s 9.2, histogram computation tool is used in
order to enhance the volume of visual information. This method is extremely vital in
identifying ground control points and rectification (Zemba et al., 2010). The five
spectrally enhanced satellite images were utilized for the image classification and re-
classification of the built-up area (Kaiser et al., 2008), as shown in Figure 3.4.
3.3.1.4. Bands Combination for Visual Interpretation
Source Landsat 5/TM, 7/ETM+ and 8/OLI_TIRs imagery used for this study
enclosed 7 and 9 spectral bands respectively. For the purpose of demonstration, 3 bands
67
of Landsat imagery were preferred which were very supportive in the collection of
training areas. Different false color band combinations were used to classify different
land uses.
Table 3.5: Band combinations in RGB comparisons
Image RBG Landsat 7 & 5 Landsat 8
Color Infrared 4, 3, 2 5,4,3
Natural Color 3, 2, 1 4,3,2
False Color 5,4,3 6,5,4
False Color 7,5,3 7,6,4
False Color 7,4,2 7,5,3
Source: http://landsat.usgs.gov/L8_band_combos.php
For example, 742 and 743 as RGB were used for identification of built-up
structure and water bodies respectively and Similarly 543 as RGB was utilized for better
recognition of vegetation cover and water. Some other band combinations of satellite
image such as 741, 321 as RGB were also considered for precise decisions about different
land uses variations.
68
3.3.2. Image Classification
Image classification is a procedure whereby all the pixels of satellite imagery are
characterized into land use land cover classes and further thematically classify each pixel
of the satellite image, based on its spectral response (Lillesand et al., 2004). Digital image
classification technique is among the most helpful procedure of satellite remote sensing
image analysis, which can be utilized for land use (LU) mapping as well as socio-
economic and other environmental applications (Lillesand et al., 2007).
Digital image classification procedure is very complicated as various factors have
to be taken into account. Main steps of images classification include; selection of the
most suitable image classification technique and its process, finding training area,
classification theme and selection of a class scheme suitable for the study area, image
classification itself and post-classification method with classification accuracy
assessment.
Image classification scheme is typically designed and based on the desired result
and the input satellite data. In case of land use mapping, the spectral pattern recognition
scheme is most appropriate. Numerous types of land use retain different blends of
radiance values forming distinctive spectral patterns (Matinfar, 2007). This system
utilizes recognition of such a pattern pixel-by pixel. Such technique helps in acquiring the
significant information about the real world. This kind of information determines to make
the thematic maps with availability of detail about the entity such as land use type;
vegetation cover, bare land, built up land and water (Bhandari, 2010).
In the broader perspective, spectrally oriented two main image classification
techniques are recognized: supervised classification and unsupervised image
classification. The information about the entities attained through the spectral reflectance
has been used by the supervised image classification in order to explain the guidance data
for designing the categories of image classification (Ratanopad and Kainz, 2006).
Supervised classification investigates spectral inconsistency which is defined
productive information according to the category. Whereas the later approach is
unsupervised image classification, an automatic classification system, where training
samples are not required at all. Unsupervised classification technique is mainly helpful in
69
making classification of the unknown areas and to evaluate the number of classes for
further supervised image classification (Kaiser et al., 2008). In remote sensing
application, supervised image classification approach has been widely used (Yuksel et al.,
2008).
Figure 3.5: Flow Chart of Image Classification Process
Minallah, 2016
3.3.2.1. Supervised Classification
The present study has adopted supervised classification technique for the time
series of Landsat images of 1973, 1980, 1990, 2000, 2010 and 2015 and set it forth as a
base data for the Spatio-temporal exploration of land use variations and determining
expansion of urban area of Lahore. In Supervised classification method, the researcher
defines the category and the numerical description in terms of computer algorithm, to
70
determine the class to which each pixel belongs. The classes were defined for the area of
interest, to have a universal classification scheme for the study.
Figure 3.6: Basic Steps in Supervised Classification
Source: Lillesand et al., 2007
Keeping in view the demography of the study area, based on prior knowledge and
literature review, four classes were defined as follows: built-up area, vacant land,
vegetation, and water bodies for the purpose of Spatio-temporal analysis. After the
supervised classification procedure, Universal color scheme was also employed and
conventional colors were assigned to each and every class. Blue color was allotted to
water bodies, dark green for vegetation, light golden for vacant land and red color was
allotted to built-up area. Table 3.6 is a description of the various land use classes.
71
Table 3.6: Description of the Land use Classification Scheme used in the Study Level I Level II
Description Main land use Sub land use Class
URBAN Urban/Built-up Area
All infrastructure: commercial, residential,
industrial areas, mixed use, and man-made
structures. It comprises areas of intensive use
with much of the land covered by structures.
Included in this category are cities, towns,
villages, settlements, pavements, road network,
highways and transportation, power, and
communications facilities.
WATER BODY Water and Wetland
This consists of areas persistently covered with
water; provided that if linear they are at least
200m wide. This category includes; River,
lakes, permanent open water, ponds, streams
and canals, lakes, reservoirs, bays and
Estuaries.
NON-URBAN
Vacant Land
Construction sites, excavation sites, developed
land, Fallow land, earth and sand land
infillings, open space, bare soils, and the
remaining land cover types. Barren Land is
land of limited ability to support life and in
which less than one-third of the area has
vegetation or other cover. Land area that is
non-cultivable and has no specific land use and
any other radiating land surface.
Vegetation
Natural vegetation, Trees, mixed forest,
gardens, playgrounds and Parks, vegetated
lands, grassland, crop fields and agricultural
lands. Agricultural Land may be defined
broadly as land used primarily for production
of food and fiber. This category includes;
Cropland and Pasture, Ornamental
Horticultural Areas.
Source: Anderson Classification System, 1980
72
3.3.2.2. Training Stage
In order to complete the supervised image classification procedure, the researcher
selected some training samples for the description of spectral characteristics of each land
use class. Selection of appropriate training samples is most important phase of supervised
classification, as each pixel of the satellite image is numerically associated to the training
set. Each pixel is allotted to a land class after considering the results of the comparison,
therefore, the training areas must be selected as accurate as possible to avoid confusion
between misclassification and the classification scheme. It must be attempted to get
training areas selected from the high resolution of satellite images or from the collected
fieldwork.
The training areas in the present research were selected with maximum accuracy
from the high resolution satellite images and also from the fieldwork. Google Earth high
resolution images were used to check each training area belonging to a specific class
(Lilesand and Kiefer, 2002). A difference is noted in the training sites from class to class
and on average, 100 pixels of training areas were nominated for each type of class. The
types of classes selected for classification of urban land use are as built-up area, vacant
land, vegetation and water bodies (Yuksel et al., 2008). Enhanced images are used for the
selection of training sites for each year, 1973, 1980, 1990, 2000, 2010 and 2015.
Region growing tool of ERDAS imagine was employed to enhance the coverage
of training area and to intensify the number of pixels for each training site. There were
several types of softwares such as Online Google Earth, Arc GIS and ENVI used to
integrate the digital topographic map with high resolution satellites images of study area
for obtaining training sites and reference to identify urban land cover changes from
images.
In the present research, the training sites obtained from the satellite images are
shown in Figure 3.7 used for classification. If the main emphasis of the study is to
investigate the urban expansion, detailed land use land cover maps are not required and
“simple binary classification” from satellite data meets the needs of the analysis by
focusing on classes of urban and non-urban land use. To ensure accuracy assessment, the
classified images are matched with land use and topographical maps of Lahore with
ground checks and relevant time period.
73
Figure 3.7: An Example of Training Samples on an Image
Minallah, 2016
3.3.2.3. Classification Stage
There are various parametric rules involved in decision designing processes of
supervised image classification, such as Mahalanobis distance, Maximum likelihood and
Minimum distance algorithms and these are available in the ERDAS Imagine 9.2 (Lu and
Weng, 2007). For the purpose of Land use mapping, good classification results can be
achieved by using the algorithm of Maximum Likelihood. In the present study, among the
three parametric rules the algorithm of Maximum likelihood was ideal and useful in this
research work because of the provision of the good classification results, comparatively to
the rest of two algorithms namely Minimum distance and Mahalanobis distance
algorithms. Maximum likelihood algorithm is simpler and provides reliable results. This
method was also useful for reclassification of classified images for built-up area
extraction in the existing research exertion. Supervised classification by using algorithm
of Maximum likelihood assumes that the probability of a given pixel falls in a specific
74
class in which stats for every class in every band are normally spread. It means that a
pixel is allocated to a specific class with the highest probability (Richards, 1999).
3.3.3. Classification Accuracy Assessment
Image classification is not valid without its accuracy assessment. There were
several reasons responsible for occurrence of errors and they come not only from the
image classification itself, but poorly selected training areas and also from image
registration etc. Therefore, it is very important to conduct an assessment of classified
result. Accuracy assessment assumes all differences between image classification
consequences and reference data derivation from the image classification errors
(Congalton and Green, 1999). The most common procedure of assessing the image
classification accurateness is confusion/error matrix (Fig. 3.8). The confusion/error matrix
encompasses a category comparison of relationship between known, ground-truth and
result of classification.
Figure 3.8: Flow Chart of Image Classification Accuracy Assessment Process
Minallah, 2016
The overall accuracy shows the accuracy process of image classification. Overall
accuracy is evaluated in percent and denotes the number of pixels properly categorized
75
and divided by the total number of pixels. Producer’s and User accuracy can be well
defined in relation to the error of omission and error of commission. Producer’s accuracy
is confined to the percentage demonstration of the specified class which can exactly be
recognized on the map. Whereas User’s accuracy is the presentation of the probability
that the specified pixel executes on the ground as it has been classified.
Kappa coefficient is a statistical quantity of agreement and measures the overall
results of image classification. The kappa measure of statistical agreement integrated off-
diagonal elements of the confusion/error matrices that were image classification error. It
also supplements in representing acquired agreement after excluding number of classes
which cause to occur error if there is strain with confusion matrix and kappa coefficient
(Foody, 2002).
Several procedures have been adopted for the evaluation of the classified images
through accuracy assessment. In the present study, some of these were practically applied
and by using the stratified random sampling techniques 270 points were collected for
comparative analysis between the each classified image and comparative assessment with
images acquired from the Google Earth and land use maps of Lahore. All these selected
points indices set forth the fundamentals to evaluate the precision assessment of the land
use classification. All classified images were vectorised into polygons after the
measurement of accuracy.
3.3.4. Post-classification Change Detection
The most effective approaches to analyze change detection processes in urban
areas include change detection algorithm and Post-classification comparison (Nadoushan
et al., 2012). After the processes of classification of images, it is often observed that the
pixels are misclassified. In order to reduce the effects of “salt and pepper” appearance of
such misclassified pixels of the images, post-classification results smooth the dominant
areas under land use. To further eliminate the salt-and-pepper effects in classification,
Median filtering by 3*3 pixels has been utilized. One of the other post-classification
techniques used in the present research is post classification change detection. The
purpose of the current research is to identify the land use changes in the study area over
approximately 42 years. There are many techniques of change detection available. In the
present study, post-classification change detection was selected because, unlike other
76
techniques of change detection, it is noteworthy that, the accuracy of this technique is
extremely dependent on the overall accuracy of classification of images used for
comparison. The consequences of post-classification change detection step include:
statistics report of change detection, and a map of change, with recognized classes to
which pixels have changed in the final date image.
3.3.5. Urban Expansion Change Detection
Urban expansion change detection for 1973 to 2015 is recorded by the usage of
Landsat TM, ETM + and OLI_TIRs data. In order to scrutinize the rate, amount, nature
and site of land expansion and land use conversion, an image of built-up structure is
extracted from satellite images. The excerpted images are overlaid to document land use
change (enlargement) image. It is further overlapped with numerous geographic reference
maps to analyze the patterns recurrent in urban expansion, including shape file of Lahore
limits and main roads. Qualitative analysis is utilized to show the measure of land use
changes which reason the intensification of urban surface temperature and its likely
reasons. For this purpose, the thermal satellite images and land use map of Lahore are
overlaid and zoomed into the target area, by Google Earth especially the hot spots
(Google, 2007).
Thermal Landsat satellite images display different temperatures in different colors
using red (hot) for high temperature and blue (cool) for low temperature. The area
congested with high density of building was displayed through more reddish color (Jusuf
et al., 2007); on the other hand, greenish will signify areas consisting of dense vegetation.
The influence of urban expansion and various land use on the urban land surface
temperature in Lahore is investigated through quantitative analysis. The urban land
surface temperature spreading through different types of land use is investigated through
making comparisons of land practice with Lahore thermal imagery taken by Landsat 5, 7
and 8 respectively from 1973 to 2015.
3.3.6. Methods of Retrieving Land Surface Temperature
LST is the radiative skin surface temperature of the land, which always plays an
imperative role in the physics of the land surface through the process of water exchanges
and energy with land to the atmosphere and determining surface radiation (Xiao et al.,
77
2008; Srivanit, 2012; Mallick, 2014). Numerous researches have been completed on the
relative hotness or “UHI effects” of metropolises by assessing the air temperature, by
metrological data.
Traditional techniques of obtaining data on temperature include; direct
observations using local meteorological weather stations. Though these weather stations
measurements have a high temporal resolution, they are expensive, time consuming and
have problems in spatial interpolation as they have local and point coverage. Satellite
sensors are capable of providing quantitative physical data at high temporal and spatial
resolutions (Fig. 3.9).
Figure 3.9: Process of Land Surface Temperature Retrieval
Minallah, 2016
78
This repetitive coverage is proficient in measuring earth surface condition
overtime (Gangulya & Shankar, 2014). At the same time, satellite remote sensing
imagery covers large areas and satellite data is much cheaper and easy to get. Nowadays
thermal infrared data is most commonly used to retrieve LST. This technique is most
convenient and suitable for the studies of urban climatology (Weng, 2009). Estimation of
land surface temperature from satellite images has been extensively utilized for urban
climate studies and adopted by many researches for studying climatology and satellite
remote sensing data available on a regular basis and free of cast. A range of algorithms
has been established to estimate LST from Landsat 5/TM, 7/ETM+ and 8/TIRS imagery,
such as single-channel method, mono-window algorithm (Munoz and Sobrino, 2003) and
radiative transfer method (Qin et al., 2001). In the present research, the radiative transfer
method is utilized to estimate the land surface temperature of Lahore.
3.3.6.1. Brightness Temperature Retrieval
To measure the land surface temperature and temporal change of temperature
from 1990 to 2015, the thermal infrared images of Landsat 5/TM, 7/ETM+ and 8/TIRS
were utilized in order to acquire surface temperature map and identify the thermal urban
environment of Lahore during 1990 to 2015. The thermal band 6 of Landsat 5/TM, 6L &
6H thermal band of 7/ETM+ and thermal bands 10 & 11 of Landsat 8/TIRs images, with
a spatial resolution of 120m, 60m and 100m respectively were used (Yuan et al., 2005;
Ma et al., 2010). They are considered suitable for taking the complex urban temperature
differences which make it possible to identify for an effective analysis of the urban
climate of the study area. The thermal Infrared bands of Landsat images were utilized to
transform the raw value into the black body temperature in Celsius Degree by using
ERDAS and ArcGIS (Joshi and Bhatt, 2012). In order to retrieve brightness surface
temperature (Fig. 3.9) three stages are given by Hashim et al., (2007).
i) Conversion of the Digital Number (DN) to Spectral Radiance (L)
L = LMIN + (LMAX - LMIN) × DN / 255 Equation No. 3.1
Where
L = Spectral radiance
79
For Landsat 5/TM
LMIN = 1.238 (Spectral radiance of DN value 1)
LMAX = 15.600 (Spectral radiance of DN value 255)
DN = Digital Number
For Landsat 7/ETM+
Band 6L = LMAX= 17.04 and LMIN= 0.0
Band 6H = LMAX= 12.65 and LMIN= 3.2
The values are obtained from the metadata header files.
For Landsat 8 can be expressed by
Lλ = ML × QCAL + AL Equation No. 3.2
Where ML stands for band multiplicative rescaling factor
(RADIANCE_MULT_BAND_DN) from the metadata (Table 3.7). On the other hand,
QCAL calibrated and quantized standard pixel values (DN), AL stand for band specific
additive rescaling factor (RADIANCE_ADD_BAND_DN) from the metadata as shown
in Table 3.7 (USGS Landsat 8 product, 2013).
Table 3.7: The Metadata of Landsat 8-TIR Rescaling Factor Band 10 Band 11
Radiance Multiplier (ML) 0.0003342 0.0003342
Radiance Add(AL) 0.1 0.1
Source: Sameen and Al Kubaisy, 2014
At the second stage, the radiance was converted to Brightness surface temperature
by using the Planck curve (Eq. 3.3) specific estimation from Landsat infrared images is
given by Chander and Markham, (2007).
ii) Conversion of Spectral Radiance to Brightness Temperature in Kelvin
Tk = K2 / 1n (K1/L+ 1) Equation No. 3.3
Where Tk stands for temperature measurement in Kelvin, K1 refers to prelaunch
calibration of constant 1 in unit of W/(m2 sr·µm). K 2 is the prelaunch calibration of
constant 2 in Kelvin as shown in Table 3.8.
80
Table 3.8: Detail of Calibration Constant Calibration
Constant
Landsat 5/TM Landsat 7/ETM+ Landsat 8/TIRs
Band 6 Band 6/1 Band 6/2 Band 10 Band 11
K1 607.76 666.09 mWcm^2 775.89 480.89
K2 1260.55 1282.71 1321.08 1201.14
Source: Sameen and Al Kubaisy, 2014
The final phase brightness temperature on Celsius (°C) can be calculated by using
following equation:
iii) Conversion of Kelvin to Celsius
TB = TK - 272.15 Equation No. 3.4
Where TB is the Brightness surface temperature in Celsius (°C), Tk is the surface
temperature in Kelvin (K) (Joshi and Bhatt, 2012).
3.3.6.2. Method of Derivation of Normalized Difference Vegetation Index (NDVI)
The NDVI is used by various researchers (Gao, 1996; Myneni et al., 2001) in
order to distinguish the land use type in the study area and it enables the analyst to
identify the correlation between land use changes and measure LST quantitatively (Zha et
al., 2003). The index value is closely associated with climatic variables, such as
precipitation and sensitive to the existence of vegetation cover on the Earth’s land surface
(Schmidt and Karnieli, 2000). In the present study, NDVI is used to observe the
relationship between Land surface temperature and vegetation cover. NDVI in Eq. (3.5)
given by Purevdorj et al., (1998), generally exploited to determine the thickness of
vegetation cover.
NDVI = (NIR - RED) / (NIR + RED) Equation No. 3.5
Calculations of the Normalized Difference Vegetation Index for a given pixel
always result in ranges from -1 to +1; indicating a value close to zero reflects absence of
greenery and a value touching +1 shows maximum density of greenery. The Normalized
Difference Vegetation Index is utilized to categorize different types of land use for
example green spaces, built-up and water, Index value ranges for all these land use
categories are inconsistent and they show variations in diverse environments and
different regions. The resulting raster file holds values ranging from -1 to +1, where
81
values around 0 relate to barren land, -1 means water, and those approaching +1 relate to
healthy and thick vegetation cover (Weier and Herring, 2008). In other words, the
Normalized Difference Vegetation Index (NDVI) value is associated to Land use classes.
Linear regression between LST and NDVI has been designed.
3.3.6.3. Land Surface Emissivity (LSE)
In this present study, the procedure of land surface emissivity assessment from the
NDVI given by Sobrino et al., (2004) and Sobrino et al., (2008) has been applied. LSE
(ε) can be extracted by using NDVI considering three different cases such as
1. Bare surface
2. Abundantly vegetated and
3. Mixture of bare soil and vegetation
0.979-0.035PR NDVI < 0.2
ε = 0.986+0.004PV 0.2 < NDVI < 0.5
.99 NDVI > 0.5
The pixels were divided, under this method, into three categories according to the
values of NDVI. If NDVI values exceed 0.5, the pixels are supposed to be covered
entirely by vegetal cover. Under such cases, the ε equal, 0.99 were assigned to them. If
NDVI values range from 0.2 to 0.5 in pixels, the Proportional Vegetation Cover (PV) was
estimated using the following equation 3.6.
Pv = [(NDVI - NDVImin) / (NDVImax - NDVImin)]2 Equation No. 3.6
Finally the emissive (ε) was acquired from simple linear regression, using the PV
values of equation 3.6 and estimation of emissive using equation 3.7.
LSE (ε) = 0.004 × PV + 0.986 Equation No. 3.7
3.3.6.4. Land Surface Temperature Retrieval
If the values of emissive are known, land surface temperature can be determined
by using simple formula 3.8.
82
LST= (TB/1+ λ*(TB / ρ)*ln (ε)) Equation No. 3.8
Where
TB= Satellite brightness temperature
λ = Wavelength of emitted radiance (11.5 µm)
ρ = h*c/ σ ______equation (1),
where
h= planck’s constant having value (6.626*10^-23 js)
σ = Blotzmann constant (1.38*10^8 m/s)
C= velocity of light (2.998*10^8 m/s)
Put the value of h, c, and σ in equation (1) we will get the value of P which is
“14380”, and then put this value in main equation.
3.3.6.5. Thermal Map Generation
The map for land surface temperature has been arranged by using appropriate
colour ramp in symbology to estimate the difference of land surface temperature. Thermal
image differencing procedure is employed to detect the degree of the land surface
temperature change (Joshi and Bhatt, 2012) during the time phase between 1990-2015.
3.3.7. Relationship between LST and Land use
In order to relate land use classes with LST, the land surface temperature maps
were filtered using Mode filter and vectorized. After the process of vectorization, both
Land use map and Land surface temperature vector map are imported to ArcGIS 10.1.
There, the Land use map was overlapped with the corresponding land surface temperature
vector. ArcGIS has been used due to its better competency for the visualization of data.
This process allowed analyzing whether the Land use classes match Land surface
temperature classes. However, the results of such overlapping are very difficult to
interpret.
Land surface temperature and land use maps of the study areas evidently explain
the correspondence of LST slices and their change in temperature from one date to
another. The operation mentioned above in methodology flow chart is specific in
83
analyzing LUC-LST relationship visually. The other alternative option is to collect
statistical data of LST and land use. For each land use class, maximum, minimum, mean
LST and its standard deviation have been calculated. Due to the nature of Land use map,
it was not possible to estimate linear regression between LST map and LUC map. An
answer to that substance is to calculate NDVI instead of land use classification result.
Normalized Difference Vegetation Index provides information about thickness of
vegetation cover and its distribution. NDVI has been calculated from Landsat imagery.
3.3.8. Regression Analysis Determining the Relationship between NDVI,
NDBI and LST
The present research utilizes linear regression analysis to estimate correlation
between land surface temperature and land use classes on NDVI and NDBI (Fig. 3.10).
NDVI and NDBI are independent variables and land surface temperature is dependent
variable. The equation of linear regression is given by Seber (2012), as under:
Y = α + βx Equation No. 3.9
Where
Y stands for the value of the dependent variable estimated from the linear
regression model.
α stands for the coefficient freedom reflecting y dependent on x.
β stands for the angel coefficient (slope) of regression line, also reflecting the
change of y variable and x variable increase one unit.
x stands for the independent variable ( NDBI, NDVI)
R2 is the coefficient of determination of the variable y, with respect to change of
the variable X. The range for R2 is 0 to 1. The more the value of R2 is, the more
dependent variable Y on variable X is.
To observe the relationship and Correlation among LST and NDVI, NDBI, about
50 random sample point sites were chosen by using Feature Class “Create Random Point
Tool” for each NDVI, NDBI and LST image (Fig. 3.11) and then by using ‘Extract Multi
values to point’ tool in ArcGIS 10.1 to get values of LST and NDVI, NDBI.
84
Figure 3.10: Regression Analysis Flow Chart
Minallah, 2016
Figure 3.11: Random Sample Points for Relationship between LST & NDVI
Minallah, 2016
Landsat 5/TM, 7/ETM+ and 8/OLI Images
Image Correction, Preprocessing
Retrieving NDVI and NDBI (Red band, near infrared and mid infrared)
Composite and subset image of the
study area
Retrieving LST Thermal band (6, 6.1., 6.2 and10, 11)
Supervised Classification Maximum Likelihood
Accuracy Assessment
Land use Map
Regression Analysis
Extracting LST for Each Land
use type
Relationship between LST and
NDBI and NDVI
85
3.3.9. Atmospheric Temperature Trends from 1951 to 2015
The time series Ground observatory data of Mean Annual Temperature (MAT),
Mean Maximum Temperature (MMxT) and Mean Minimum Temperature (MMiT), as
well as selected urban expansion parameters i.e. growth of population, change of land
use, increase number of vehicles, increased number of factories and increased greenhouse
gases since 1950-2015 are analyzed in this study by statistical methods (Table 3.9).
Linear regression and the Pearson correlation were applied (Table 3.9) for analyzing
significant changes in temperature trend in particular span of time and to find out the
causes of such changes.
The present research is aimed at finding out the factors and reasons for
temperature change and locating the contributing factors existing between natural and
anthropogenic activities. The determined trends exist in a certain magnitude. First of all,
the data are compiled and MAT, MMxT, MMiT were computed on mean monthly and
annual basis. The data are compiled afterwards and scatter plots are used to analyze
structures of temperature trends by using SPSS 20 in order to select the test type, i.e.
Kendal tau, spearman of linear data to examine time series of temperature trends.
The variables in graph of the data after plotting are observed from the lower left-
hand corner to the upper-right edge. Simple Linear regression test was utilized to analyze
the temperature trend during the study span. When the data is parametric, the Simple
linear regression analysis provides the statistical test for the inquiry of relationship
between different variables. Mostly, the researchers investigate the causal effects of one
such variable upon another. It also helps in determining the relationship that exists
between the variables in a lucid manner. It also estimates the value of intensification
between both the variables, independent and dependent.
On the other hand, employing another statistical test, Pearson correlation is used
to investigate the causal relationship between different variables to find out contributing
factors. The statistical values in Pearson correlation, value ranges between ±1 and +1
show positive correlation, indicating an increase in both the variables. Similarly, a
negative correlation in the variables indicates that increase in one variable causes
decrease in the value of the other variable. In this study, the hypothesis is; “Multifarious
factors cause change in temperature trends in Lahore”. To conduct linear regression along
86
with Pearson correlation (Table 3.9) on MAT, MMxT and MMiT data time series is as
under;
Table 3.9: Procedure of Applied Statistical Test
Datasets Analysis Statistical Test Procedure
A MAT, MMxT and MMiT
Trends for
6.5
decades
Simple Linear
Regression
Analyze
Regression
Linear
B
Indicators of Urban Expansion
Population Growth
Built-up area Increase
Reduction in Agricultural
land
Increase no. of Vehicles
Increase no. of Factories
Increase Greenhouse Gases
Causes Pearson’s
Correlation
Analyze
Correlation
Bivariate
Minallah, 2016
A. MAT Trend analysis for whole phase (1950-2015):
I. Dependent: (a) MAT; (b) MMxT; (c) MMiT
II. Independent(s): Year (Time Unit)
In the section of analysis, quantitative measurement of annual temperature, along
with its various parameters, are utilized as dependent variable and time period on annual
basis is used as independent variable. The analysis is done using the formula given by
Seber, (2012) as under
Y = + x + e Equation No. 3.10
Where,
Y-Outcome of atmospheric temperature of Lahore (A) a) MAT b); MMxT; and c) MMiT
87
X - Time unit: (A) year
+ x - Linear (systematic) relation between Y and X
- Mean of Y when X=0 (Y-intercept)
- Variation in mean of Y when X increases (slope)
e - Random error term
In the formula, the datasets of coefficients, R square and significance tests are
interpreted for each data time series of temperature. In addition, the R2 statistics tabulated
in model summary, which can be used to calculate the regression model for outcome
predictions. It shows intensity of variable and degree of correlation between them. It can
explain the variations in the dependent variable with predictive efficiency of the model
and changing trends (Seber, 2012).
3.3.10. Software used in Analysis
Software programs run as from ESRI and Leica Geosystems are utilized to get the
analysis required for the results by processing the satellite images and to store, analyze
and manifest information. The present research work utilized ERDAS Imagine 9.2,
ARCGIS 10.2 and ENVI 4.7 for the image analysis including image pre-processing,
image processing and image classification, accuracy assessment, making of change
detection map and retrieving land surface temperature and driving NDVI, NDBI. The GIS
software, ARCGIS 10.2 is utilized to generate the thermal maps, urban expansion and
land use change maps. The other client software, an open source gySIG-GIS was
explored for visualization of satellite images. Microsoft office, including MS Word, MS
Excel and MS Access and SPSS 20, Mini tab were also used for the description, statistical
analysis and tabulation of land use data and analyzing the urban expansion and change
occurred during the study period and also used for graphical representation of analysis.
88
CHAPTER 4: URBAN EXPANSION OF LAHORE, 1951-2015
4.1. Introduction
The world is witnessing an unprecedented urban growth in the recent times. For
the first time in the history of urban growth, world has achieved momentous milestone in
2008 when more than half of the population of the world lived in towns and cities (UN,
2009). Population growth and urbanization go together and economic development is
closely correlated with urban expansion. An increase is noted in the urban areas
expanding rapidly throughout the world, therefore, the present century is termed as
"urban century" (Shirazi, 2011; GoP, 2013). Towns and Cities are growing in population
as well as in their geographic footprint and anthropogenic activities at an accelerating
pace (Blair, 2012).
An unprecedented urban population growth is recorded in Pakistan as well as in
Lahore along with unplanned developmental activities leading to the process of
urbanization and urban expansion. This massive growth in urban population in towns and
cities needs adequate management in terms of urban development planning, urban
population problems and land use change using efficient monitoring techniques and tools.
The current situation can be quantified by accurate information and reliable prediction for
the future expansion trends and to make comprehensive plans for the valuation of the land
use changes in the specific area. Data regarding population (including growth rate and
spatial distribution) and information about the change of land use patterns are required.
Both of these areas coordinate with each other as the population growth influences the
urban expansion and development exercising pressure on land use in respect of increase
in built-up land, demand for more housing in new sectors, the provision of transportation,
appropriate infrastructure, reduction in agricultural land and vegetation and degradation
of environment in general.
Monitoring and assessment of urban expansion and identification of Spatio-
temporal land use changes and respective disparities in urban settlements have now
become significant fields of study as the proportion and number of the urban population
continues to increase day by day throughout the world as well as in Pakistan. Since
Lahore is the 2nd largest city of Pakistan and provincial capital of the province of Punjab,
it has displayed significant areal expansion leading to developmental activities including
89
construction of buildings, roads and other anthropogenic activities since the day of
partition 1947 onwards. It is also one of the ancient and densely populated cities of
Pakistan as well as South Asia.
It is the economic, political, educational hub and major cultural centre for
Pakistan. Lahore is among the thirty largest cities of the world as it shares 22% urban
population in the province of Punjab, Pakistan. Lahore can be compared with the other
cities of the world having Spatio-demographic nature in terms of urban reality. In 2015,
Lahore had more than 9.5 million population and can be termed as a metropolitan city.
The spatial and physical expansion of the city is not only on linear pattern but also
sectoral and marginal because it has occupied the vacant areas and consumed most the
agricultural area of Lahore. The urban structure of Lahore is dynamic in nature as shown
by the behavior of urban expansion.
The land use changes and urban expansion can be monitored efficiently through
multi-spectral satellite remote sensing data. Urban expansion and morphological patterns
have been a vital issue in geographic researches. The significance of remote sensing for
the assessment of urban expansion and observing land use changes and their dynamics are
highly acknowledged. A number of researches have been conducted on analyzing the
significance of mapping in urban areas for monitoring land use and their changes utilizing
satellite data sets during the last two decades (Dewan and Yamaguchi, 2008). The
combination of GIS and RS is comprehensively applied and renowned as powerful and
precise tool in identifying urban land use changes providing reliable accuracy and results
along with clear images of urban expansion. This study, explores the urban expansion and
detects land use changes of Lahore, Pakistan during the periods from 1972 to 2015
through RS techniques.
In this chapter, the land use changes in the city of Lahore and dynamic process of
urban expansion are presented. This chapter is divided into two sections; first comprising
section highlighting temporal population growth of the city of Lahore for the period of
1951-2015. The results are shown in the bar graph, line graph and population distribution
maps of Lahore with the help of statistical analysis. Second phase of the chapter will
describe the urban expansion of Lahore from 1951 to 1972 (Pre-satellite Era) as the
growth of the city started mounting from 1951 onwards. The data for the aforesaid period
(1951 to 1972) was collected by using publications and maps as satellite images were not
90
in practice. The Spatio-temporal urban expansion and land use changes in Lahore from
1972–2015 (Satellite Era) were assessed through satellite images using remote sensing
and GIS techniques.
4.2. Population Growth of Lahore from 1901 to 2015
Population is major focus of all the related studies in geography as relying on the
population and the available resources are intimately connected, displaying the prospects
of urban expansion, land use change, development, land surface temperature and
environment in the specific region. Man, as a habitant, is consumer of all the biotic and a -
biotic resources besides being an important resource himself (Shirazi, 2011). It is,
therefore, the study of growth of population and its distribution is rationale preliminary
point for executing any type of research of the present nature. The focus of the present
research is to investigate the growth of population in the previous decades and to observe
the spatial distribution and temporal growth of population in the present decade for the
benefit of future planning and projection of future population growth rate. These factors
directly or indirectly affect the land resources of the study area. The dichotomy has ended
between the rural and urban areas under the devolution plan. In 2001, the devolution plan
was introduced in Pakistan ensuing local body election with the endorsement of local
government ordinance. Officially it was labeled as Local Government Plan whereas it
was named as Devolution Plan 2000 publically. A district includes a Tehsil in the
jurisdiction (both in urban and rural areas), while a City District comprises administrative
towns. The details of the population growth in the Lahore city (including Metropolitan
Corporation and Cantonment) have also been included in the present research as new set-
up by LDA in 2004 (LDA, 2004).
4.2.1. Population Growth of Lahore from 1901-1941
The population of Lahore, as reported in 1941 census was 671659. The population
of Lahore has increased for about 25 times since the start of the 20 th century as shown in
Table 4.1. In 1901, the population of Lahore was 202964 and 671659 in 1941, while the
population of the country (Pakistan) was recorded to be 1,657,700 to 28,282,000 for the
same span of time. The yearly population growth rate from 1901 to 1921 was rather slow
and can be attributed to under enumeration of population and difficulty in areal coverage.
Since then, the rate of population growth sustained till independence (1947) and then
91
accelerated at the rate of 4.31 and 4.57 % during the period of inter-censual from 1921-31
and 1931-41 respectively.
Table 4.1: Population, Growth Rates and Intercensual Increase of Lahore 1901-1941
Census
Year
Population Inter-censual Increase (%) Avg. Annual Growth
Rate (%)
Lahore Pakistan Lahore Pakistan Lahore Pakistan
1901 202964 16577000 - - - -
1911 228687 19382000 12.67 16.9 1.20 1.6
1921 281781 21109000 23.22 8.90 2.11 0.9
1931 429747 23552000 52.51 11.50 4.31 1.1
1941 671659 28282000 56.29 20.10 4.57 1.9
Source: GoP, 1951
Figure 4.1: Population Growth of Lahore from 1901 to 1941
Source: GoP, 1951
Figure 4.2: Inter-censual Increase and Growth Rates of Lahore from 1911 to 1941
Source: GoP, 1951
0
100
200
300
400
500
600
700
800
1901 1911 1921 1931 1941
Pop
ula
tion
(0
00
)
Year
0%
10%
20%
30%
40%
50%
60%
1911 1921 1931 1941
Perc
en
tag
e
Year
Inter-censual Increase (%) Avg. Annual Growth Rate (%)
92
4.2.2. Population Growth of Lahore from 1951 to 2015
In the urban hierarchy of Pakistan, the city of Lahore ranks second among the
major cities. It is the 2nd largest metropolitan city of Pakistan in terms of population after
Karachi as well as the 2nd largest urban center in the country for economic activities.
Besides, it is also the largest metropolitan city of the Punjab and provincial capital (Table
4.2). About 54.6 % of urban population of Pakistan resides in big cities: Karachi. Lahore,
Faisalabad, Multan, Rawalpindi, Gujranwala, Hyderabad, Peshawar and Quetta (Jan et
al., 2008). A growth of 3% is reported per year, from 2000 to 2005 and similar growth
has been predicted for the next decade (GoP, 2010). The population growth of Lahore
mounted higher than the rate of increase in the country. The detail regarding the
population growth is given below in census periods (Table 4.3).
Table 4.2: Rank of Lahore among the Major Cities of Pakistan Since 1951
S. No. Rank
1951 1961 1972 1981 1998
1 Karachi Karachi Karachi Karachi Karachi
2 Lahore Lahore Lahore Lahore Lahore
3 Hyderabad Hyderabad Faisalabad Faisalabad Faisalabad
4 Rawalpindi Faisalabad Hyderabad Rawalpindi Rawalpindi
5 Multan Multan Rawalpindi Hyderabad Multan
6 Faisalabad Rawalpindi Multan Multan Hyderabad
7 Sialkot Peshawar Gujranwala Gujranwala Gujranwala
8 Peshawar Gujranwala Peshawar Peshawar Peshawar
9 Gujranwala Sialkot Sialkot Sialkot Quetta
10 Quetta Sargodha Sargodha Sargodha Islamabad
Source: GoP, 2009
Table 4.3: Population Increase in Lahore from 1951 to 2015
Census
year
Inter-
censual
Period
(year)
Lahore District Lahore Urban
Population
Inter-censual
Increase (%) ACGR** Population ACGR**
1951 10 1,134,757 - - 861,279 -
1961 10 1,625,810 43.3 3.66 1,312,495 4.30
1972 11 2,587,621 59.2 4.06 2,189,530 4.48
1981 9 3,544,942 37.0 3.79 2,988,486 3.75
1998 17 6,318,745 78.3 3.46 5,209,088 3.32
2010* 12 8,650,000 26 2.69 7,097,000 2.65
2015* 15 9,545,000 - 7,846,000 -
*Estimated **Annual Compound Growth Rate
Source: GoP, 2000; GoP, 2015
93
Figure 4.3: Population Growth of Lahore from 1951 to 2015
Source: GoP, 2015
In 1951, the population of city of Lahore was 1.135 million which increased to
1.626 million in a decade, 1961. The average annual growth for the decade was about
3.7%, marked with an increase of 0.491 million people in inter censual period. The total
increase in population in the decade, 1951-1961 was reported to be 43.3% (GoP, 1961).
During the next period of 1961-1972, the increase in population was 1.626 million to
2.588 million. The average growth rate was 4.1 % while 1.326 million people were added
in the overall population of the Lahore. The increase in inter-censual span was 59.2 %
(GoP, 1972).
The massive increase in the growth owes to different factors contributing towards
urban growth in terms of population after independence, 1947. One of the major factors
of population shift towards urban areas was political. West Pakistan was declared as ‘one
unit’, and the culture center was Lahore, inviting people from far off areas to migrate
towards Lahore for better prospects of living. In 1972, the increase was reported to be
2.588 million which led to 3.545 million in 1981. The average annual rate of increase was
3.8% while 0.957 million people were added to the population of Lahore (GoP, 1984).
This decade, as compared to the last one noted a decrease in the population annual growth
rate. In fact, it was for the first time that the government of Pakistan realized the need for
the necessary measurement to be taken in terms of coping with the massive increase in
population. After 1972, a decrease in the rate of population was recorded.
0
2,000
4,000
6,000
8,000
10,000
12,000
1951 1961 1972 1981 1998 2015
Pop
ula
tion
(0
00
)
Census Year
94
After the census of 1981, the next census was held in 1998. The increase was
reported to be 2.774 million in Lahore. The increase was 3.545 million in the year 1981,
6.319 million in 1998 with an average growth of 3.5% per annum. The inter censual
period, ranging from 1981 to 1998 demonstrated 78.3% increase in the respective
population growth. The last census held in 1998, the population of the Lahore city was
officially reported to be 6.319 million, for about 4.77% of the total population of the
country (GoP, 2000). After the last census held in 1998, no preceding censual data could
be collected. The next national census was scheduled to be conducted in 2008. But it
could not be conducted due to deterioration of peace and non-availability of military and
civilian personnel required for the collection of the population data. Then, sixth national
population census was rescheduled to be held in March 2016 but again it was postponed.
In short, population census could not be materialized for one reason or the other. The
current population of Lahore can be estimated through projection equation (4.1) for 2015
given by Riaz, (2011).
Pt+17 = P1 + rP1 Equation No. 4.1
Pt+17 in the equation stands for the time of population Projection, P1 stands for the
population as recorded in the last census and r stands for the growth rate for the specific
period.
It is also estimated by applying the above mentioned equation that the population
of Lahore has increased to 9.5 million in 2015 as compared to 6.319 million in 1998. The
estimate of the government was 9.545 million people for the year 2015, whereas the same
figure is calculated by the researcher. During the period, almost 3.226 million people
were declared to be added in the total population of Lahore.
4.2.3. Population Growth Rate of Lahore from 1951-2015
Since the day of independence, Lahore has witnessed an enormous increase in the
population that amounted to be 1.135 million in the year 1951, leading to an increase in
1998 figuring the population calculation to 6.319 million. Although, the rate of overall
population growth rate in Pakistan had declined to 2.61% in 1998, whereas the rate of
growth in 1972 was 3.66% (GoP, 2000).
95
The growth rate sustained in Lahore for two main factors. First of all, Lahore is
the largest urban center of Punjab, and one of the most advance cities of the country. It
provides better medical facilities and maintains superior standards of living. Its increase is
bound to be natural, contributing mass exodus from the rural areas and occupying spaces
in the metropolitan city of the nearest access. Secondly, Lahore is a hub of socio-
economic, cultural and political activities for the people across the country, especially the
province of Punjab, inviting the people to migrate for better prospects.
Table 4.4: Population Growth and Inter-Censual Increase in Lahore from 1951-998 Description 1951 1961 1972 1981 1998
Population (000) 1135 1626 2588 3545 6319
Inter Censual Increase (%) - 43.3 59.2 37.0 78.3
Average Annual Growth (%) - 3.7 4.1. 3.8 3.5
Source: GoP, 2000; GoP, 2015
Figure 4.4: Average Annual Growth rate and inter-censual increase from 1951-1998
Source: GoP, 2000
4.2.4. Population Distribution and Density of Lahore
Lahore has dispersed population. Its metropolitan limits are condensed while 61
settlements in the district house more than 5000 inhabitants. Before the introduction of
PLGO in 2001, Lahore had two tehsils in terms of administration, 1) Lahore Cant 2)
Lahore city tehsil. The census in 1998 reported the population to be 3.78 million (59.8 %)
in Cantonment tehsil while occupying 51.75 % of the total area of Lahore and 2.54
0
10
20
30
40
50
60
70
80
90
1951 1961 1972 1981 1998
Perc
en
tag
e
Census Year
Inter-censual Increase (%) Average Annual Growth Rate (%)
96
million (40.2%) people in Lahore city tehsil while occupying 48.25 % of the total area of
Lahore (GoP, 2000).
Table 4.5: Tehsils of Lahore and population in 1998
Sr.
No. Name of Tehsil
Area
(Km2)
Population
(million)
Population
Density Per km2
Urban
Population
1 Lahore Cantonment Tehsil 917 3.78 4,120 82.8
2 Lahore City Tehsil 855 2.54 2,971 81.9
Total Area & population of Lahore 1772 6.32 3,565 82.4
Source: GoP, 2000
By knowing the density of an area, one can depict the living conditions of that
particular area. For instance, areas with higher density are known to be problematic areas
in terms of necessary facilities and other utilities. Lack of open spaces in congested areas
is likely to spread epidemics and other viral diseases. Even the social values related to the
population residing in those areas are quite different to as compared with the values of
those who reside in low density areas. The total population of Lahore was 6.319 million
while the total area was 1772 Sq. Km in 1998. The population density is 3566 person per
sq. km as compared to the density recorded in 1981, i.e. 2001 persons per Sq. km. In
1972, the density was recorded to be 1460 persons per Sq. km. earlier, in 1961, it was 918
persons per Sq. km while in 1951, the density was 641 persons per Sq. km. (GoP, 2000).
Table 4.6: Population Distribution and Density of Lahore from 1951-2015
Year Area (Sq. Km) Population (000) Population Density per Sq. Km.
1951 1772 1,135 641
1961 1772 1,626 918
1972 1772 2,588 1,460
1981 1772 3,545 2,001
1998 1772 6,319 3,566
2010* 1772 8,650 4,881
2015* 1772 9,545 5,386
* Estimated Population
Source: GoP, 2015
Lahore population density is designed with the aid of following formula:
Gross Density = Total population / Total area (km2) = Persons/km2 4.2
According to the calculations, the estimated density of Lahore increased to 5276
persons per Sq. km. in 2014. Lahore, being a city district, can be termed as ‘City Proper’.
97
The term City Proper refers to the locality within the fixed boundaries, along with the
recognition of being an urban area by the respective government. According to these
standards, Lahore can be titled as the 30th amongst the most densely populated cities of
the world (UN, 2004). If the population growth maintains the same pace, it would be the
20th most densely inhabited metropolitan across the globe by 2025. The structure of
administrative units in Pakistan has been changing over the past years. These
administrative units have been used for the censuses conducted so far, making temporal
analysis complicated for the development practitioners and researchers in developing
countries. In 1998, the situation changed after the promulgation of Local Government
Ordinance (LGO, 2001) in Pakistan.
The administrative bodies were changed and the district was partitioned into city
districts, towns/tehsils and union councils. The administrative structure of Lahore, the
largest metropolitan city of the Punjab province and the 2nd largest city of the country was
announced as City District Government Lahore (CDGL) and was divided into six towns.
It was re-examined and three more towns were further added to CDGL. At present, the
Lahore City District governs nine (09) towns which are administrated under the
supervision of Town Municipal Administration (TMA), besides Lahore Cantonment.
Figure 4.5: Population Density of Lahore from 1951-2015
Source: GoP, 2015
The six (06) sub towns with respect to areas i.e. Shalimar Town (15km2), Gulberg
Town (32km2), Data Ganj Bukhsh Town (33km2), Samanabad Town (35km2), Ravi
0
1000
2000
3000
4000
5000
6000
1951 1961 1972 1981 1998 2005 2010 2015
Pop
ula
tion
Den
sity
Year
Population Density per Sq. Km.
98
Town (62km2) and Aziz Bhatti Town (89km2), are clustered in the north-western side of
Lahore, while the area wise three (03) larger towns i.e. Wagha Town (435km2), Iqbal
Town (464km2), Nishtar Town (520km2) are mainly located towards east and southern
side of Lahore as shown in Figure 4.6.
Lahore is spread over 1772 Sq. Km. and 80 per cent area of Lahore is covered by
three larger towns including; Wagha Town (435km2), Iqbal Town (464km2), and Nishtar
Town (520km2) while Shalimar Town has the least area of about 15 Km2 i.e. less than 1% of
total area of Lahore. The areas of the remaining five (05) towns i.e. Gulberg Town, Data Ganj
Bukhsh Town, Samanabad Town, Ravi Town and Aziz Bhatti Town occupy between 2 to 5% of
the total area of Lahore. These administrative towns are further sub divided into 150 union
council level, 128 urban while the rest are rural and one cantonment as stated in the Table
4.7.
Table 4.7: Town wise Urban and Rural Union Councils of Lahore Name of Town Area Km
2 Total UC’s Urban UC’s Rural UC’s
Aziz Bhatti Town 89 11 7 4
Data Ganj Bukhsh Town 33 18 18 -
Gulberg Town 32 15 15 -
Iqbal Town 464 15 6 9
Nishtar Town 520 19 11 8
Ravi Town 62 30 30 -
Samanabad Town 35 19 19 -
Shalimar Town 15 11 11 -
Wagha Town 435 12 5 7
Cantonment 87 - - -
Total 1772 150 122 28
Source: GoP, 2015
The average gross density in terms of persons per Sq. Km was the highest in
Shalimar Town (25,933) and the lowest in Wahga Town (1,106) in 1998. As per 1998
census data, gross population density of each town has been calculated using its area and
total population. The density is calculated on basis of number of persons per Sq. Km.
The overall density of Lahore was 3566 persons per Sq. Km in 1998. In the year
1998, the density of Shalimar Town was the highest (25,933), while that of Wahga Town
and Allama Iqbal Town was lowest (1,106 and 1,222 respectively). The population
density of the remaining towns varies from 1,411 to 21,576 persons per Sq. Km as shown
in Table 4.8 and Figure 4.6.
99
Table 4.8: Population Densities of Nine Towns of Lahore (1998)
S. No. Town Population 1998 (000,s) Area
Km2
Density
1998 Km2 Urban Rural Total
1 Aziz Bhatti Town 264 150 414 89 4,652
2 Data Ganj Bakhsh Town 712 - 712 33 21,576
3 Gulberg Town 571 - 571 32 17,844
4 Allama Iqbal Town 218 349 567 464 1,222
5 Nishtar Town 403 331 734 520 1,411
6 Ravi Town 1163 - 1163 62 18,758
7 Samanabad Town 722 - 722 35 20,629
8 Shalimar Town 389 - 389 15 25,933
9 Wahga Town 201 280 481 435 1,106
10 Cantonment 566 - 566 87 6,506
TOTAL 6319 1772 3566
Source: GoP, 2010
Figure 4.6: Town wise Population Distribution and Density of Lahore in 1998
Minallah, 2016
The population estimation of 2010 indicates that the overall population density of
Lahore is 4881 persons per Sq. Km. In TMAs, the densest town is Shalimar Town, 35,333
persons per Sq. Km. Data Gunj Baksh Town demonstrates 29,393 persons per Sq. Km
and Samanabad Town shows about 28,114 persons per Sq. Km. The least density is noted
to be in Wahga Town, 1508 persons per Sq. Km., Nishtar Town 1923 persons per Sq.
100
Km. and Allama Iqbal Town 1665 persons per Sq. Km. The density is shown in Table 4.9
and Figure 4.7.
Table 4.9: Population Densities of Nine Towns of Lahore (2010 Estimates) S.
No. Town
Population 2010 (000,s ) Area
(Km2)
Density
2010 Km2 Urban Rural Total
1 Aziz Bhatti Town 355 210 565 89 6,348
2 Data Ganj Bakhsh Town 970 - 970 33 29,393
3 Gulberg Town 778 - 778 32 24,312
4 Allama Iqbal Town 285 488 773 464 1,665
5 Nishtar Town 538 462 1000 520 1,923
6 Ravi Town 1585 - 1585 62 25,564
7 Samanabad Town 984 - 984 35 28,114
8 Shalimar Town 530 - 530 15 35,333
9 Wahga Town 263 393 656 435 1,508
10 Cantonment 809 - 809 87 9,298
TOTAL 8,650 1,772 4,881
Source: GoP, 2010
Figure 4.7: Town wise Population Distribution and Density of Lahore in 2010
Minallah, 2016
The population estimation of 2015 shows that the overall density of Lahore
increased to 5,386 persons per Sq. Km. Similar increase is noted to be in the density of
Shalimar Town, 39,000 persons per Sq. Km. and remains the most thickly populated area
101
so far. It is followed by Data Gunj Baksh Town, 32,424 persons per Sq. Km., and remains
secondly densely populated town in TMAs.
Table 4.10: Population Densities of Nine Towns of Lahore (2015 Estimates)
S.
No. Town
Population 2015 (000,s) Area (Km
2)
Density
2015 Urban Rural Total
1 Aziz Bhatti Town 395 228 623,000 89 7244.18
2 Data Ganj Bakhsh Town 1070 - 1,070,000 33 32424.24
3 Gulberg Town 859 - 859,000 32 26843.57
4 Allama Iqbal Town 318 535 853,000 464 1838.362
5 Nishtar Town 599 505 1,104,000 520 2123.076
6 Ravi Town 1749 - 1,749,000 62 28209.67
7 Samanabad Town 1086 - 1,086,000 35 31028.57
8 Shalimar Town 585 585,000 15 39,000
9 Wahga Town 293 431 724,000 435 1705.74
10 Cantonment 892 892,000 87 10252.87
TOTAL 9,545,000 1,772 5386.568
Source: GoP, 2015
The town in the third place is Samabad Town, 31028 person per Sq. Km and the
least densely populated town are Wagha Town, 1705 persons per Sq. Km., Nishtar Town
2123 persons per Sq. Km. and Allama Iqbal Town 1838 persons per Sq. km. the figures
are shown in Table 4.10 and Figure 4.8.
Figure 4.8: Town wise Population Distribution and Density of Lahore in 2015
Minallah, 2016
102
The density map of Lahore as shown in Figures 4.6 to 4.8 reveals that high density
zones are in the walled city and its adjacent eastern and southern localities where density
goes even beyond 800 persons per hectare. Like other urban centers, density is high in the
central zone and gradually lower towards the peri-urban areas. Some intermediate zones
like; Ichhra, Babu Sabu, Sanda also display higher density due to decentralization of
activities.
4.2.5. Urban and Rural Population of Lahore
Since 1951, the total population of Lahore has tremendously increased. This
population explosion indicates that Lahore has the potential of growing into a metropolis.
Owing to this massive growth, Lahore was given the status of city district in 2002.
Besides the districts considered to be the city, it also has many rural vicinities. The
population of various administrative towns (as shown in Table 4.11) in Lahore has
increased with fluctuating Annual Compound Rates (ACGRs) as recorded in inter-censual
periods. The rate of urban population growth of Lahore has continuously been declining
since 1972. During the period of 1961-72, it was 4.48%, further reduced to 3.75 % during
1972-81 and declined again in 1981-98 at 3.32 %. The overall growth rate of Lahore has
also been subject to decline but the pace is comparatively slow. The rate of growth of
whole district and urban area was almost the same during 1972-81. The rate of urban
growth declined a bit as compared to the overall growth rate (3.75%, earlier 3.79%).
Table 4.11: Population of Lahore & its Constituent Administrative Units
Name of Towns Total Population (000,s) Urban Population (000,s)
Urban
Population
1998 2010 * 2015 * 1998 2010 * 2015 * 1998 (%)
Aziz Bhatti Town 414 565 623 264 355 393 63.8
Data Ganj Bukhsh 712 970 1070 712 970 1070 100
Gulberg Town 571 778 859 571 778 859 100
Iqbal Town 567 773 853 218 285 318 38.4
Nishtar Town 734 1000 1104 403 538 599 54.9
Ravi Town 1163 1585 1749 1163 1585 1749 100
Samanabad Town 722 984 1086 722 984 1086 100
Shalimar Town 389 530 585 389 530 585 100
Wagha Town 481 656 724 201 263 293 41.8
Cantonment 566 809 892 566 892 892 100
Total 6,319 8,650 9,545 5209 7,097 7,846 82.4
*Estimated
Source: GoP, 2000; 2010; 2015
103
During the period of 1981-98, the difference was further declined. The rate of
urban growth was reduced to 3.32% as compared to 3.46% for the whole area of Lahore
as shown in Table 4.12. During the period of 1972-98, the growth of urban population
grew from 2.19 million to 5.21 million, however the proportionate Lahore urban
population declined from 84.62 percent to 82.44 percent during 1981 to 1998 (Table
4.13).
Table 4.12: Lahore Urban Population & ACGR (1951-1998) & 2015 Estimated
Census
Year
Inter-censual
Period (Years)
Lahore District Lahore (Urban)
Population ACGR (%) Population ACGR (%)
1951 10.00 1,134,757 - 861,279 -
1961 10.00 1,625,810 3.66 1,312,495 4.30
1972 11.67 2,587,621 4.06 2,189,530 4.48
1981 8.46 3,544,942 3.79 2,988,486 3.75
1998 17.00 6,318,745 3.46 5,209,088 3.32
2010* 12.00 8,650,000 2.69 7,097,000 2.65
2015* 14.00 9,545,000 7,846,000
*Estimated
Source: GoP, 2000; 2004; 2010; 2015
Since 1951, the rate of urban growth of Lahore has increased almost nine times.
The rural population in contrast has increased just five times the formal figure. Table 4.13
indicates that the urban population has always been subject to massive increase with a
rapid pace than that of rate of growth or rural population. In 1951, the urban population of
Lahore was 0.861 million that increased in 1962 to 1.312 million. During the inter-
censual period between 1961-72, 0.877 million of people were added to the urban total
and further 2.190 million people in 1972.
The urban population of Lahore in 1981 increased to 2.988 million and further
increased to 5.209 million in 1998 (GoP, 2000). According to an estimate, the projected
urban population of Lahore has grew up to 7.846 million in 2015 (Table 4.13). The
comparison of urban and rural population growth of Lahore as shown in Table 4.13 and
Figure 4.9 indicates that urban population is growing much more rapidly than the rural
population. This massive increase can be attributed to the sprawling limits of the city
encroaching over the rural vicinity. Villages in the vicinity of Lahore were merged into
104
the urban area. All these villages have merged into the urban territory of Lahore and the
respective population is considered to be a part of urban population.
Many rural localities of the Lahore vicinity have been merged into the city district
of Lahore. This rapid urban growth owing to the transformation of rural areas into urban
areas paced the areal expansion. New housing schemes have been established to house the
masses in the Lahore settlement. All such housing societies sprang at the cost of
agricultural land. The rural settlements comprising more than five thousand inhabitants.
Besides these, there are also a large number of smaller villages which have been merged
into urban areas.
Table 4.13: Urbanization (1951-1998) in Lahore and 2015 Estimates
Census
Year
Population Inter
censual
change
(%)
Proportion of
Urban
Population
(%)
Lahore
Total pop.
Lahore
Urban
Inter
censual
increase (%)
Lahore
Rural
1951 1,134,757 861,279 53.31 276,000 12 75.90
1961 1,625,810 1,312,495 66.2 309,000 28.8 80.73
1972 2,587,621 2,189,530 36.4 398,000 40 84.62
1981 3,544,942 2,988,486 74.33 557,000 99.2 84.30
1998 6,318,745 5,209,088 51.1 1,110,000 31.3 82.44
2010* 8,462,000 6,944,000 - 1,518,000 - 82.06
2015* 9,545,000 7,846,000 - 1,699,000 - 82.20
*Estimated
Source: GOP, 2000; 2010; 2015
Figure 4.9: District, Urban and Rural Population of Lahore
Source: GoP, 2015
0
1,000
2,000
3,000
4,000
5,000
6,000
7,000
8,000
9,000
10,000
1951 1961 1972 1981 1998 2010* 2015*
Pop
ula
tion
(0
00
)
District population Urban Population Rural Population
105
4.3. Urban Expansion of Lahore from 1951 to 2015
Urban expansion which is regarded as a form of urban growth (Bhatta, 2009)
takes place in multi-dimensional ways, such as increased residential clusters, revival of
built-up areas, introducing new urban areas, which were non-urban areas before. Urban
expansion resulted in encroachment in natural setup such as green belts, agricultural land,
and forest, vacant land and water bodies etc. and consequently natural setup turned into
built-up areas (Angel et al., 2005). Urban expansion has not only affected population but
it has also disturbed environmental ecosystem such as water scarcity, deforestation,
floods and rise in land surface temperature. Rapid population growth, industrial
expansion and growth in commercial activities enhanced the urban expansion (Puertasa et
al., 2014). This situation has been experienced in many cities of developing countries
particularly Pakistan such as Lahore. Such kind of development is seen along major road
networks and new residential colonies in unplanned and haphazard manner. In obvious
changes which are seen in economic activities, industrial extension and rapid
urbanization, researchers are of the view that urban expansion is triggered by
demographic change. Increasing population needed more residential land. It is not wrong
to say that developing countries like Pakistan, rapid increase in population is one of the
major driving forces behind urban expansion and city growth. In order to examine the
nature, amount, rate, location and trends of urban land use change of Lahore, an image of
built-up area is take out from Landsat classified images. During the study span from 1972
to 2015, classified images of built-up area are overlaid to get spatial and temporal urban
expansion map and land use changes of Lahore are observed.
Figure 4.10: Urbanization and Built-up area Trends of Lahore
Source: GoP, 2015; Minallah, 2016
0
2
4
6
8
10
12
1973 1981 1990 2000 2010 2015
0
100
200
300
400
500
600
700
Pop
ula
tion
(m
illi
n)
Urb
an
Bu
ilt-
up
lan
d (
Km
2)
Urbanized Land Population
106
4.3.1. Historical Expansion of Lahore: Pre-1947
Lahore is historical cultural hub of Punjab province, dated back to 1000 years.
Historians have declared Lahore as most attractive, most fascinating and majestic city of
Pakistan as well as South Asia. Loh, son of Rama Chandra, laid down foundation of
Lahore 2000 years ago. The earliest metropolitan city remained prominent through
various reigns, either Hindu or Mughal, Sikhs and British (IMPL-2004). Lahore invites
the inhabitants who are desirous to have urban character. Over centuries, Lahore has
distinctive geostrategic location in subcontinent because of its rich and unique socio-
cultural heritage, combining with urban infrastructure and development including a vast
number of gardens. That is why, Lahore was named “city of gardens” during Mughal
epoch. This Mughal legacy was enhanced through construction of building, parks and
green spaces during the British rule particularly the constructions concerned with Lahore
Cantonment and civil lines. During past decades, rapid urbanization changed the land use
profile of Lahore.
Lahore has always tended to be metropolis in terms of physical infrastructure
since 1947, creation of Pakistan. Extensive road network was laid. Community water
supply system was improved. Educational institutes, hospitals, bus service and radio
broadcasting were there. The municipal corporation had been working as separate public
body for decades. Lahore Improvement Trust (LIT) was established for city planning and
development. Foundation of modern infrastructure for Lahore was laid (Qadeer, 1983). A
large mass of population migrated to Lahore from India at the time of independence. As a
result, population of Lahore city increased. Besides the massive increase in urban
population, the areal expansion has become apparent now-a-days as compared to the past.
It may be ascribed to the division of sub-continent that affected the urban population
distribution in the country. After that Lahore experienced steady and consistent spatial
growth. Lahore Improvement Trust started new residential projects in fifties and sixties e.
g. Gulberg, Samanabad and Upper Mall scheme etc. LIT has succeeded by LDA, which
also made great contribution in development projects, housing schemes and planning
sector including industrial areas, airport and university campuses and commercial areas. It
is necessary to express here that these development projects and planned schemes have a
great contribution in Lahore development. Urban expansion map of Lahore depicts clear
picture regarding Lahore urban development in south and southeast directions (Fig. 4.11).
107
The River Ravi act as a barrier in urban expansion in north and west direction. Similarly
Indian border checked in eastward expansion of the city.
Figure 4.11: Urban Expansion of Lahore from 1850 to 2015
Minallah, 2016 (Edited)
108
Economic progress in the country leads to physical and infrastructural
development and expansion. This is done because of petrodollar in seventies. Internal
migration (from countryside to city) triggered development and expansion of the city. The
physical growth in last six decades is marked by major road networks such as Ferozepur
road, GT road and Multan road. In addition, it has shaped into rectangular developed area
in north south direction. After 70’s, speedy development is seen in city along the Canal
bank, the Mall, Mayo and Lytton road. Many planned and unplanned residential schemes
were launched and they have obvious impact on current setup.
4.3.2. Urban Expansion of Lahore from 1951 to 1972 (Pre-Satellite Era)
Lahore is a historic city of Pakistan. At the time of independence of Pakistan, in
1947, the urban area of Lahore, comprised Walled city, Misri Shah, Mughalpura,
Baghbanpura, Chah Miran, Naulakha, Gari Shahu, Qila Gujjar Sing, Ichhra, Qila
Lachman Sing, Mozaang, Kirshan Nagar, Sant Nagar, Nawan Kot, Raj Garh, Ram Nagar,
Model Town and Cantonment Area. Figure 4.12 (a & b) shows the urban expansion of
Lahore since 1947 to 1972, the period also called as pre-satellite era. The total urban
built-up area was 66 km2 in 1951 as shown in the Figure 4.12a. After the partition of
India and Pakistan, the massive mass of people migrated across the border through
Lahore to reach Pakistan, as it was one of the gateways to enter the territory of Pakistan.
Moreover, Lahore was the major urban and industrial center at that time, providing
employment to the immigrants.
Since 1951 Lahore has grown at unprecedented rate. This unrestrained urban
expansion shifted transportation terminals from the suburbs of railway station to the other
areas of the city. In spite of this settlement, railway station still exists as the junction of
intra city transport. There is no sole CBD in Lahore. There are several business districts
in the city along major roads and highways. The congestions and overpopulated CBD
forced people to migrate to the outer periphery from the inner district of the city. These
peripheries are less populated and congested where there is less air and noise pollution.
At present, CBDs along Ferozpur road and GT road are present. The ring road circling
around the city is also a major reason for the establishment of industrial and residential
suburbs.
109
Figure 4.12: Urban Expansion of Lahore from 1947 to 1972
Source: Ghaffar, 2006
In 1960s new housing settlements appeared such as Samanabad, Wahdat Colony,
Gulberg, Shadbagh, Bahawalpur House, Shadman, Poonch House, Shah Jamal, Muslim
Town and New Garden Town. During the next period of 1951-1965, total urban built-up
area was noted to be 170 km2 in 1965 as shown in Figure 4.12b. Since 1961, the
population growth of Lahore began to increase at a higher rate. During the period
between 1961 to 1972, the population of Lahore increased steadily from 1.63 million in
1961 to 2.59 million in 1972 with average annual population growth rate of 4.06%. With
the passage of time, urban built-up area of Lahore also expanded. A several number of
new housing settlements were established with the passage of time including Joher town,
Faisal Town, New Garden Town, and Allama Iqbal Town and were further added to the
urban built up area of Lahore in order to cope the ever increasing population growth of
the city during the period 1961-1972.
4.3.3. Land use changes of Lahore from 1972 to 2015
In order to observe the patterns of urban expansion and magnitude, extent, trends
and rate of land use changes of Lahore, supervised image classification for the year 1973,
1980, 1990, 2000, 2010 and 2015 are executed and surface land were characterized into
level I classes scheme (Anderson, 1976). For identifying land use changes, based on prior
knowledge and review of literature, Maximum likelihood Algorithm (MLA) is used in the
present research in view of the demography of the study area.
Lahore is divided into four main classes; which includes 1) Urban/Built-up area,
2) Vacant Land, 3) Agriculture Land and 4) Water Bodies. The visual demonstration and
110
quantification can be very effective for the interpretation of the study area statistics. The
urban land use map of Lahore for the year 1973, 1980, 1990, 2000, 2010 and 2015 is
presented in Figure 4.13 to 4.18, and the area change statistics, percentage and rate of
change for each urban land use class during the study span are individually presented in
Table 4.14 and 4.15.
There are numerous ways to measure and monitor the land use changes and their
results. Among others, one of the basic techniques is to tabulate the data and quantify the
total land use changes for each land use type and observe the trends of land use change
between the different years. During the study span, distinct changes have happened on the
key land surface. The major changes of urban land use were evaluated as given below in
Table 4.14.
Table 4.14: Area Statistics and Percentage of Land use of Lahore from 1973-2015
Year
Land use Type Total
Area
(Km2)
Built-up
Area
Vacant
Land
Agricultural
Land
Water
Bodies
1973 Area Km2 223.96 320.02 1213.23 14.79 1772
% 12.64 18.06 68.47 0.83 100
1980 Area Km2 273.29 305.44 1170.57 22.70 1772
% 15.42 17.24 66.06 1.28 100
1990 Area Km2 352.75 277.74 1117.82 24.17 1772
% 19.91 15.67 63.08 1.36 100
2000 Area Km2 445.12 242.23 1062.25 22.40 1772
% 25.12 13.67 59.95 1.26 100
2010 Area Km2 517.43 230.69 1004.99 18.89 1772
% 29.20 13.02 56.72 1.07 100
2015 Area Km2 643.51 196.34 915.71 16.44 1772
% 36.32 11.08 51.68 0.93 100
Source: Computed from Landsat Imagery
111
Figure 4.13: Land use Distribution of Lahore in 1973
Minallah, 2016
Urban land use profile of Lahore changed extensively from 1973 to 1980. In 1973,
the urban/built-up land of Lahore was 223.96 Km2 which increased to 273.29 Km2 in
1980. The portion of built-up area increased from 12.64% in 1973 to 18.06% in 1980. It is
also revealed that the agricultural land decreased from 1213.23 Km2 in 1973 to 1170.57
Km2 in 1980, while area under vacant land decreased from 320.02 Km2 in 1973 to 305.44
Km2 in 1980 (Table 4.14).
During the period from 1973 to 1980, the built-up area increased about 49.33 Km2
(22%) while agricultural land reduced 43 Km2 (4%), vacant land decreased 14 Km2 (5%)
(Table 4.14). The key factor of this rapid urban expansion was the growth of population
of Lahore. Population of Lahore increasing rapidly, reached 3.54 million in 1981 which
was about 2.58 million in 1972. About 1 million people were increased in just one
decade. This increasing population needed more land for the purpose of new settlements
and commercial activities. So the agricultural land turned into built-up areas for new
housing schemes. Figure 4.13 and 4.14 depicts land use patterns of Lahore in 1973 and
1980 respectively. The expansion of the city started in south ward direction.
112
Figure 4.14: Land use Distribution of Lahore in 1980
Minallah, 2016
During the second period from 1980 to 1990, the land use change of Lahore
became slightly rapid than the preceding period (1973-1980). The urban built-up area of
Lahore increased from 273.29 km2 in 1980 to 352.75 km2 in 1990. After this expansion
the share of urban/built-up land augmented from 15.42% in 1980 to 19.91% in 1990
(Table 4.14). During this phase, the urban/built-up land of Lahore increased 79.46 Km2
(29%) while agricultural land constantly transformed and decreased 53 Km2 (5%) while
vacant land decreased 27.70 Km2 (9%) was altered into urban/built-up area during 1980-
1990 (Table 4.15). Land use changes of Lahore in 1980 and 1990 are shown in Figures
4.14 and 4.15. The maps show the main urban expansion of Lahore on the southern side
of city. It is noted that agricultural and vacant land was altered into urban land. It can be
analyzed through maps that urban territory increased while there has been decline in
vegetation and agricultural land.
The years from 1990 to 2000 beheld a phenomenal increase in the urban
expansion of Lahore. The urban built-up area of Lahore increased from 352.75 km2 in
1990 and 445.12 km2 in 2000. The net accumulation of more than 92.37 km2 in
urban/built-up land during the period 1990 to 2000 has transformed from vacant and
113
agricultural land use to urban built-up environment and changed the land use profile of
Lahore. The land used for agriculture reduced from 1117.82 km2 in 1990 to 1062.25 km2
in 2000. The agricultural area reduced and its share in the total land decreased from 63%
in 1990 to 59.95% in 2000 (Table 4.14).
During this period (1990-2000), the urban/built-up land increased considerably 92
Km2 (33%) while vegetal cover constantly altered and decreased 56 Km2 (5%), vacant
land decreased 35 Km2 (13%) and was transformed into urban/built-up area during 1992-
2000 (Table 4.15). That is the time when government decided to deliberate the whole of
Lahore as the city district. The settlements adjacent to the limits of Lahore are also
included in the urban area. New housing schemes round about 110 and commercial areas
were approved to meet the residential need of increasing population, at the expense of
agricultural land as well as vacant land.
Figure 4.15: Land use Distribution of Lahore in 1990
Minallah, 2016
It is demonstrated from the Figures 4.15 & 4.16 that the expansion in the urban
area during the period mostly expanded towards south, south western and western part of
the district. During the period from 1990 to 2000, the urban growth of Lahore was
tremendous. Lahore had never experienced such a rapid expansion in the history, owing
114
to the massive population in the period. The population in the period increased from 4.83
million in 1990 to 6.76 in 2000 (GoP, 2000). The major expansion took place along
Ferozpur, GT and Riawind road. The fact lying behind the urban expansion in these
directions is the availability of large area of open spaces, pollution free environment, and
availability of good water quality and establishment of many public and private
initiatives.
Figure 4.16: Land use Distribution of Lahore in 2000
Minallah, 2016
Digital image classification shows that the growth of urban built-up area was at a
slower rate during the period between 2000-2010. The main emphasis was not on the
decrease in the urban population, rather it focused on the development aligning the
approved housing schemes. The urban/built-up land of Lahore increased from 445.12 km2
in 2000 to 517.43 km2 in 2010. The areas calculated by the author and calculated by the
SUPRRCO Pakistan are same in the year 2010. The share of built-up area in Lahore
increased from 25.12% in 2000 to 29.20% in 2010. From 2000 to 2010 the urban/built-up
land increased 72.31 km2 (16%) while agricultural land reduced 57.26 km2 (5%) and
11.54 km2 (5%) vacant land reduced from the land use profile of Lahore (Table 4.15).
115
Figure 4.17: Land use Distribution of Lahore in 2010
Minallah, 2016
Figure 4.18: Land use Distribution of Lahore in 2015
Minallah, 2016
116
The share of vacant and agricultural land decreased from 13.67% in 2000 to
13.02% in 2010 and 59.95% in 2000 to 56.72% in 2010 respectively. The land use map of
Lahore (2000, 2010) is shown in Figures 4.16 & 4.17. In 2010 the outcomes indicated
that the total built-up area in Lahore was 517.43 km2. It increased to 643.51.48 km2 in
2015, thus recording a massive growth of urban built-up land 126.08 km2 (24%) during
this time period 2010 to 2015 as shown in Figures 4.17 and 4.18, while agricultural land
was continuously converted and reduced 89 (9%). The share of total urban/built-up area
of Lahore enlarged from 29.20% in 2010 to 36.32% in 2015.
The area under use for agricultural purpose was reduced from 1004.99 km2 in
2010 to 915.25 km2 in 2015, while the vacant land reduced from 230.69 km2 in 2010 to
196.34 km2 in 2015. The total share of agricultural land reduced from 56.72% in 2010 to
51.68% in 2015 (Table 4.14) as a large part of it was converted into built-up land. The
result shows a rapid expansion of built-up land in general increased from 1973 to 2015,
by 187% with the greatest increase occurring from 1980 to 1990, 29% in 10 years.
Agricultural land, vacant land extent decreased by 38%, 24% respectively and mostly
they were converted to built-up area and urban land uses from 1973 to 2015 (Table 4.15).
All these relative trends are further demonstrated in Figures 4.19 and 4.20.
4.3.3.1. Nature, Rate and Extent of Land use Change
In order to determine the magnitude, extent and rate of change of land use change
in the area under study, following variables are measured.
Ta = Total area
Ca = Changed area
Ce = Change extent
Cr = Annual rate of change
These variables can be illustrated by the following formula:
I. Ca= Ta (t2)-Ta (t1);
II. Ce=[Ca/Ta (t1)]x100;
III. Cr=Ce/(t2-t1); Where t1 is the beginning and t2 is ending time of the urban land
used for the research conducted and the outcome was illustrated in Table 4.15
(Yesserie, 2009; Beza, 2011).
117
The average annual rate of change in urban/built-up land determined from the
image analysis land use change area statistics was 3% from 1973 to 1980, 2.9% from
1980 to 1990, 2.6% from 1990 to 2000, 1.62% from 2000 to 2010, 4.9% from 2010 to
2015 and 4.5 % for the whole study period of 1973 to 2015. This indicates a vivid change
in urban expansion and morphology of Lahore according to its extent and size.
Furthermore, agriculture land and vacant land showed an average reduction of change
approximately -0.5 to 2.98% annually. In general, the change values in the Table 4.15
showed that increase in urban built-up areas mostly originated from transformation of
other land uses in particular agriculture land to urban land uses (i.e. Built-up area) during
the past 42 years (1973-2015) following increasing development pressure within the
Lahore. Figures 4.19 and 20 portrayed the nature of relative land use change trends from
1973 to 2015 in Lahore. The areal extent of urban built–up area observed positive
increasing trends while all the study period agricultural area and vacant spaces showed
continuous decreasing trends.
Table 4.15: Overall amount, rate, nature and extent of land use change 1973-2015 Land Use 1973-1980 1980-1990 1990-2000
change
(∆/km2
)
Extent
(%)
Rate
of ∆
(%/yr)
change
(∆/km2)
Extent
(%)
Rate
of ∆
(%/yr)
change
(∆/km2)
Extent
(%)
Rate
of ∆
(%/yr)
Built-up 49.33 22.03 3.15 79.46 29.08 2.91 92.37 26.19 2.62
Vacant land -14.58 -4.56 -0.57 -27.70 -9.07 -0.91 -35.51 -12.79 -1.28
Agriculture -42.66 -3.52 -0.50 -52.75 -4.51 -0.45 -55.57 -4.97 -0.50
Water 7.91 53.48 7.64 1.47 6.48 0.65 -1.77 -7.32 -0.73
Land Use 2000-2010 2010-2015 1973-2015
change
(∆/km2
)
Extent
(%)
Rate
of ∆
(%/yr)
change
(∆/km2)
Extent
(%)
Rate
of ∆
(%/yr)
change
(∆/km2)
Extent
(%)
Rate
of ∆
(%/yr)
Built-up 72.31 16.25 1.62 126.08 24.37 4.87 419.55 187.33 4.46
Vacant land -11.54 -4.76 -0.48 -34.35 -14.89 -2.98 -123.68 -38.65 -0.92
Agriculture -57.26 -5.39 -0.54 -89.28 -8.88 -1.78 -297.52 -24.52 -0.58
Water -3.51 -15.67 -1.57 -2.45 -12.97 -2.59 1.65 11.16 0.27
Source: Computed from Table 4.14
118
Figure 4.19: Nature of Relative Land use Change of Lahore from 1973 to 2015
Minallah, 2016
Figure 4.20: Land use Changing Trends of Lahore from 1973 to 2015
Minallah, 2016
4.3.4. Temporal Urban Expansion of Lahore from 1972-2015
Urban expansion of Lahore denotes the growth of built-up area. First of all, built-
up area was extracted based on four land use type data by using GIS techniques with the
help of Arc/GIS 10.2 and got respectively temporal urban expansion maps of Lahore for
the year 1973, 1980, 1990, 2000, 2010, 2015 (Fig. 4.22 & 4.23) and calculated area of
expansion during the study period from 1973-2015 (Table 4.16).
Table 4.16: Comparison of Built-up and Non Built-up Area of Lahore
Year 1973 1980 1990 2000 2010 2015
Urban/Built-up Area (Km2) 223.96 273.29 352.75 445.12 517.43 643.51
Non Built-up Area (Km2) 1533 1476 1395 1304 1236 1112
Water 14.8 22.7 24.17 22.4 18.89 16.44
Total Area (Km2) 1772 1772 1772 1772 1772 1772
Source: Computed from Landsat Imagery
0
200
400
600
800
1000
1200
1400
Built-up Area Vacant Land Agriculture Land Water Bodies
Are
a (
Km
2)
Land use Profile of Lahore
1973 1980 19902000 2010 2015
0
200
400
600
800
1000
1200
1400
1973 1980 1990 2000 2010 2015
Are
a (
km
2)
Years
Built-up Area Vacant Land Agriculture Land Water Bodies
119
The key concern of the present research was to assess temporal urban expansion
from 1973-2015 with prior emphasis on the major land use type of urban built-up area
and non-built-up area. The comprehensive land use type maps were no longer required
and a simple binary class like urban built-up area from satellite remotely sensed data is
sufficient (Bhatta, 2009). The reclassification maps of Lahore land use type with two
main classes includes built-up are and non-built area comparison are shown in Figure
4.21. Table 4.16 depicts the results evaluated from satellite imagery after reclassification.
Figure 4. 21: Comparison of Built-up and non-built-up Area of Lahore
Minallah, 2016
Figure 4.22: Temporal Change in Urban Expansion of Lahore in 1973 and 2015
Minalla, 2016
223.96 273.29352.75
445.12 517.43643.51
1533 14761395
1304 12361112
0
500
1000
1500
2000
1973 1980 1990 2000 2010 2015
Are
a (
Km
2)
Years
Urban/Built-up Area Non- Built-up Area
120
Figure 4.23: Temporal Urban Expansion of Lahore from 1973 to 2015
Minallah, 2016
121
The land use map got after reclassification of Landsat imagery into two category
provides visual images of temporal expansion of the study area (Figures 4.22 & 4.23).
These temporal urban expansion maps of Lahore provide the proof of the confirmation
about the temporal land use dynamics of Lahore during the study period (1973-2015).
These temporal maps (Figures 4.22 and 4.23) deliver particulars about the nature, rate
extent and overall amount of urban built-up land change during the period (1973-2015) in
Lahore.
4.3.5. Annual Rate of Urban Expansion from 1972 to 2015
Temporal expansion and change of urban area are computed by annual growth
rate. In order to discuss annual growth rate of urban expansion, an estimation index
(ARU) is designed given by Wang and Bao, (1999); Zhu and Li, (2003); Xiao et al.,
(2006); Li et al., (2009); Haregeweyn, et al., (2012); Xu & Min, (2013) and it is defined
as follows:
𝐀𝐑𝐔 =𝐔𝐢−𝐔𝐣
𝐔𝐢 ×
𝟏
𝐓 × 𝟏𝟎𝟎% E Equation No. 4.2
Where ARU is Annual Rate of Urban Expansion; Ui and Uj represent the
urban/built-up areas at the beginning time and ending time for a certain study span (1972-
2015), respectively. T signifies the time that study period covers.
Table 4.17: The Urban area, ARU and increasing urban area of Lahore Year 1973 1980 1990 2000 2010 2015
Urban Area (Km2) 223.96 273.29 352.75 445.12 517.43 643.51
ARU (%) - 3.14 2.80 2.61 1.62 4.87
Increase Urban area (km2) - 49.33 79.46 92.37 72.31 126.08
Minallah, 2016
During the last 42 years, the urban/built-up area of Lahore has increased 419.55
km2 from 223.96 km2 in 1973 to 643.51 km2 in 2015 and the Annual rate of urban
expansion has increased. The result indicated that during the study period (1972 to 2015)
Lahore as a whole, retained a very high growth of increasing urban/built-up area in past
42 years (Table 4.17). The fastest growing period is in 2010–2015, when the ARU
touches 4.87%, and the second faster one is in 1973–1980, when the ARU is about
3.14%, and the third faster one is 1980-1990, when the ARU is about 2.8%. It can be
122
established that urban expansion of Lahore also slowed down between 1990-2000 and
2000-2010 at the rate of 2.6 % and 1.6 % respectively.
4.3.6. Urban Expansion Intensity Index
Intensity of urban expansion is a spatial unit that can define the rate of urban
expansion in different study periods, so it can be utilized to quantitatively link the
intensity of urban expansion at different study periods. The formula given by Liu et al.,
(2000); Hu et al., (2007); Zhou et al., (2009) and Gao et al., (2011) can be stated as
follows:
Ei = ΔA ⋅ 100 / A . Δt Equation No. 4.3
Where: Ei signifies intensity index of urban expansion, ΔA denotes the
transformation area of non-urban built-up area to urban built-up area. A signifies the total
area of study area, Δ t characterizes interval of computing period (in year).
Table 4.18. Indices of urban temporal expansion of Lahore during different periods
Indices 1973-1980 1980-1990 1990-2000 2000-2010 2010-2015 1973-2015
Expansion
area (km2)
49.33 79.46 92.37 72.31 126.08 419.55
Expansion
rate (km2)
7.04 7.94 9.24 7.23 25.22 9.98
Expansion
intensity (%) 0.39 0.45 0.52 0.41 1.42 0.56
Minallah, 2016
Table 4.18 shows that indices of temporal urban expansion and intensity of
expansion during different periods have been calculated by using the equation number
4.3. The urban/built-up area of Lahore was respectively 223.29 km2 in 1973, 273.29 km2
in 1980, 352.75 km2 in 1990, 445.12 km2 in 2000, 517.43 km2 in 2010 and 643.51 km2 in
2015 (Table 4.14). The annual average expansion rate was 9.98 km2 in the past 42 years,
the period extending from 1973 to 2015, and the urban built-up area was expanded to
419.55 km2 with an expansion intensity of 0.56% as shown in Figure 4.22. During the
period from 1973 to 1980, the temporal patterns of urban expansion indicated that the
urban area of Lahore grew at annual average expansion of 7.04 km2, with an intensity of
0.39%, an expansion area of 49.33 km2. Urban area expanded towards the southward
direction, along with the major roads. During the period of 1980 to 1990, an increase in
the urban expansion rate and intensity was noted. The urban/built-up area expanded by
79.46 km2 with an intensity of 0.45%, along with an annual average expansion rate of
123
7.94 km2. The Figure 4.23 presents the temporal urban expansion from 1980 to 1990. It is
indicated in the maps that the urban expansion of Lahore majorly occurred towards the
southern side of Lahore. Moreover, the land under agricultural use and forest area was
altered to urban land use. During the period of 1990 to 2000, there was observed an
increase in the urban expansion rate and intensity. The urban/built-up land expanded by
92.37 km2 with the intensity of 0.52% and annual average expansion rate of 9.24 km2. It
is indicated in the Figure 4.22 that the expansion during the period 1990-2000, has
occurred majorly towards south, along with south western and the western portion of
Lahore. During the period from 2000 to 2010, a slightl decline in the intensity and
expansion rate was observed. The urban/built-up area expanded by 72.31 km2, with the
intensity of 0.41 % and annual expansion rate for 7.23 km2. The period from 2010 to
2015, there was a massive increase in the urban expansion recorded to be 126.08 km2
with an intensity of 1.42% and annual average expansion rate of 25.22 km2.
4.3.7. Urban Change Detection of Lahore from 1973-2015
The land use change detection has been analyzed through post classification
technique of multi-temporal Landsat satellite imagery of 1973 to 2015. The post
classification technique specifies “from-to” change evidence. This classification approach
supports in mapping and measuring the phenomenon of conversion of land in urban
landscapes. The Spatial information of expansion of urban area is worthwhile to
comprehend the urban expansion direction in different periods from 1973-2015 (Figures
4.24 and 4.25). The post classification evaluation technique is very useful for data
acquired through different sensors with different spectral and spatial resolution.
This technique was used to detect land use changes, by analyzing independently
processed classified land use maps. The main feature of this method is its ability to
deliver expressive information on changing trends. This approach mainly depends on the
results of the classified images and data stored in GIS database. GIS provides compatible
medium for post-classification appraisals and facilitates qualitative valuation of the
factors, which has impact on urban expansion. GIS system has been utilized to
incorporate urban/built-up land class for the six time series and a thematic map was
generated to analyze trend of urban expansion as shown in Figures 4.24 and 4.25. During
the study span from 1973 to 2015, it was obvious that the urban/built-up areas expanded
in southeast, south and southwest direction of Lahore.
124
Figure 4.24: Urban Change Detection of Lahore from 1973 to 2015
Minallah, 2016
125
Satellite remote sensing implication proved to be effective in creating change
detection map (Figures 4.24 and 4.25), and is very useful in spatial understanding about
single entity and productive in analyzing, changing statistics and comprehensive visual
description of data. 1973-1980 era is supposed to be first spatial urban expansion period.
During this study span, there is 50 km2 increase in urban built-up area. Spatial patterns of
urban expansion depict that there is growth in built-up area while there is decline in
agriculture and vacant land. Most remarkable change in form of spatial urban expansion
is shown in southern side during this period. Urban expansion was rapid in 1980-1990
decade as depicted in Figure 4.24. It is evident from map that the urban spatial expansion
of Lahore occurred primarily on southern side of Lahore by converting vacant and
agricultural land into built-up area and urban uses.
Figure 4.25: Spatial Expansion of Lahore from 1973 to 2015
Minallah, 2016
Phenomenal increase in urban spatial expansion of Lahore is seen during the
period 1990-2000. During the period (1990-2000), the rate of the encroachment of
urban/built up areas expanded much more extensively in the similar direction of the
preceding period. It is clear from the Figure 4.25 that the urban spatial expansion during
this time frequently took place in the south, south western and western part of Lahore.
126
It is apparent from the study period during 1990-2000, there was extraordinary
urban spatial expansion of Lahore. Lahore had never experienced such a rapid physical
expansion throughout the past. Classified image analysis of decade (2000-2010) showed
slower urban expansion in this period. The rate of urban expansion during this period
slightly declined. It does not imply that population growth of Lahore decreased. The fact
lying behind this slower growth is development of existing approved housing societies.
One of the major factors behind the urban expansion during the period 2000 to 2010 is
encroachment of urban built-up areas, occupying extensively over agriculture and vacant
land which was reduced by 58 km2 & 12 km2 respectively. However the expansion of
urban/built up areas increased 126.08 km2 toward agricultural area more than vacant land
during 2010-2015.
Figures 4.24 and 4.25 depict an apparent Spatio-temporal urban expansion of
Lahore through the change detection maps of Lahore. Urban expansion encounters all
urban features and spread of urban area all over Lahore. The classified image results
show a noticeable expansion in populated communities. Urban expansion is more obvious
in southeast, south and southwest and western direction. Moreover Agricultural land
transformed into built-up area. Overlay analysis (Figure 4.25) of built-up area shows the
trends of change in 1973-2015.
4.4. Classification Accuracy Assessment
An imperative course of action related to the digital image classification is
accuracy assessment of the results after classification. This accuracy assessment has been
designed by confusion/error matrices. It is the most frequently used technique for per-
pixel image classification accuracy (Lu and Weng, 2007). Random selection of the
samples was done to avoid biased assessment of results (Jensen, 2005). 150 Ground
Control Points (GCPs) were designated for each land use class. Fieldwork strategies were
adopted and GPS device was used for the collection of comparison of sampled pixels
along with their corresponding land use type on ground. The accuracy assessment of the
historical satellite images for the period of 1973, 1980, 1990, 2000, 2010 and 2015 was
carried out by using following methods.
First of all, GCP sample points, collected randomly, were validated through field
observations for the land without any change in the period of the study, such as forests,
water bodies and ancient buildings. Secondly, additional confirmation of these land use
127
areas was made through published map and census report of population. The process of
accuracy assessment proceeded after picking up several test samples for each satellite
image for recognized classified results. Google images and base maps were used for
authentication and reference. The following Figure 4.26 indicates the descriptive example
of test samples of satellite image for accuracy assessment. Test samples are white in
colour before confirmation by using reference images. After confirmation, they were
turned to yellow.
Figure 4.26: An Example for Test Samples on an Image for Accuracy Assessment
Minallah, 2016
The accurate results are evident in Table 4.20, 4.21 and 4.22 indicating user
accuracy and producer accuracy, kappa index of agreement and over accuracy for all six
images. The user accuracy and producer accuracy for each images are calculated
separately. Error matrix was also drawn for the accuracy of the images.
The results drawn from the thematic Landsat MSS images for the years 1973 and
1980 certified the accuracy of 78.67% and 82.47 % respectively. Similarly, the Landsat
images of TM, ETM, OLI_TIRs of 1990, 2000, 2010 and 2015 indicate the accuracy of
Test Samples
128
85%, 87%, 89 % and 92% respectively. The four images of TM, ETM, and OLI/TIRs
system for the years 1990, 2000, 2010 and 2015 demonstrate a little higher accuracy as
compared to the MSS images of the year 1973 and 1980. This slightly higher result may
be due to the higher spectral, spatial and radiometric resolution. This analysis was good
enough for the accurate assessment and acknowledgement in terms of analyzing urban
change detection. The producer’s accuracy ranged from 50 % to 97% while the user’s
accuracy ranged from 60% to 86% for each land use class type.
Table 4.19: Overall Classification Accuracy and Kappa (κ) Statistics 1973 1980 1990 2000 2010 2015
Overall Accuracy (%) 78.67 82.47 85.00 87.42 89.66 92.67
Overall Kappa (k) 0.5349 0.7242 0.7701 0.8145 0.8385 0.8808
Minallah, 2016
Table 4.20: User’s and Producer’s Accuracy for each Land use type
Land use 1973 (%) 1980 (%) 1990 (%) 2000 (%) 2010 (%) 2015 (%)
P U P U P U P U P U P U
Built-up Area 76.9 71.4 82.2 78.1 90.4 89.1 93.5 92.1 97.1 92.9 94.1 96.0
Vacant Land 50.0 64.7 67.6 92.0 63.6 87.5 68.4 86.6 65.0 81.2 85.7 85.7
Agriculture 88.4 82.8 88.8 86.7 89.8 84.5 90.2 83.6 94.5 89.6 96.1 94.8
Water Bodies 50.0 62.5 70.0 60.0 73.3 68.7 78.9 83.3 72.7 80.0 85.7 66.6
*P for Producer Accuracy and U for User Accuracy
Minallah, 2016
Table 4.21: Conditional Kappa for each Category
Class Name Conditional Kappa (K)
1973 1980 1990 2000 2010 2015
Built-up Area 0.6872 0.7305 0.8317 0.8653 0.8844 0.9394
Vacant Land 0.5864 0.8973 0.8576 0.8475 0.7881 0.8424
Agriculture Land 0.4418 0.7204 0.7242 0.7529 0.8210 0.8947
Water Bodies 0.5982 0.4653 0.6591 0.8093 0.7865 0.6503
Minallah, 2016
Kappa index of agreement for each classified image is shown in the Table 4.19.
The results of the Kappa index of agreement is 53% for 1973, 72% for 1980, 77% for
1990, 81% for 2000, 83% for 2010 and 88% for the year 2015. The numerical visibility
regarding producer’s accuracy and user’s accuracy is shown is tabulated in Table 4.20 for
129
each land use type. Throughout the study period, image classification from 1973 to 2015,
the lowest user’s accuracy and the producer’s accuracy were not calculated. However, the
higher user’s and producer’s accuracies were detected for the urban built-up and
agricultural land classes due to much consideration of research for the change in urban
land use and urban expansion analysis.
130
CHAPTER 5: LAND SURFACE TEMPERATURE VARIATIONS
5.1. Introduction
The environmental changes are continually occurring on the Earth’s surface
because of urban development and expansion, as natural greenery and agricultural land
are turned into non-transpiring surfaces like metal asphalt and concrete. Such changes
produce the urban-rural disparity with relevance to air and land surface temperature.
Increasing urban development is seen all over the world particularly in developing
countries like Pakistan. It is necessary to keep the effects of such change in land use on
the climate in check. At the moment, global change in temperature is the biggest issue
surrounding mankind. It is vital to realize such alterations at a small scale since the
city/regional scales show more human population density and influences of such
atmospheric changes can be sensed on these scales. For the analysis of natural
environment affected by urban expansion, land surface temperature is one of the key
indicators and this indicator is governed by vegetation. In the present research, land
surface radiant temperature is retrieved from radiometrically corrected Landsat thermal
images of Lahore from 1990-2015. An attempt is made in this study to observe the land
surface temperature variations in correspondence with NDVI, NDBI indices and land use
changes, and their effects on Land surface temperature of Lahore. A predictive regression
model is developed which is an appropriate and convenient way to find a correlation
existing between the changes in land use and temperature.
In this chapter, the results that highlight the outcomes of the research are
discussed. The presented findings of the present research describe the prospective of land
surface temperature change as well as highlight the certain urbanization parameters i.e.
rapid population growth, land use changes, increasing number of registered vehicles,
increasing number of factories and greenhouse gases , as various factors of air and land
surface temperature change. Secondly, in this chapter, three different data time series of
MMiT, MMxT and MAT of metrological data are used to discuss the trends and temporal
changes in atmospheric temperature from 1950 to 2015, with emphasizing their root
causes in order to comprehend likely effects. To examine the significant change detected
in land surface temperature variation with the passage of time, linear regression and
Pearson correlation method are applied respectively. Moreover, this chapter also
131
encompasses the discussion on the spatial variations of land surface temperature in
Lahore. In addition, some of the hotspots of temperature are also pointed out.
The land use dynamics of Lahore have been indicated in the different time spans,
demonstrating variant thermal environment effects in different areas of urban expansion.
Moreover, the study further establishes the correlation that exists between NDVI, NDBI
and LST of Lahore. Finally the massive scale of hot spot is observed, over the densely
populated and industrial areas, where the urban heat islands are likely to develop, whereas
the cold areas are observed over the green spaces and water bodies.
5.2. Factors Increasing Land Surface Temperature
Earth’s climate is subject to so many influences that can be categorized into
natural and anthropogenic (human-induced) factors. Scientists have been conducting
observations in the climatic change due to the factors other than any natural influences of
the past since the beginning of the 20th century. The change in the climate, referred to as
Global warming, happened rapidly as compared to the other climate changes observed in
the past and that is why it yields greater importance to human population. With rapid
population growth and economic advancement, the influence of human activities on the
temperature has increased. The mean maximum and minimum temperature of Lahore
recorded to be 30.8°C and 17.8°C.
Figure 5.1: Factors Increasing Land Surface Temperature
Minallah, 2016
Population Growth
Urban Expansion/Lan duse Changes
Increase No. of Vehicles ,
& No. of Factories per year
Transformation of Natural Cover to Urban
Structure i.e. Impervious Surfaces
Air and Land Surface Temperature Rising
132
Urban population growth is one of the most important existing geographic
phenomena all over the world. The process of rapid urban expansion of Lahore was
recorded since 1951, ultimately increasing air and land surface temperature. The major
factors of this rapid urban expansion including education and health facilities,
employment opportunities, industrial and commercials activities in urban centers have
been contributing towards urban migration, a mass exodus of the people from rural to
urban centers. Due to this massive migration, urban centers expand day by day. Urban
expansion is the alteration of natural land cover to land use accompanying with urban
population growth and economic activity. Urban areas covered with impervious surfaces
such as buildings, road networks and steady built-up structures have higher ratio of solar
radiations, greater thermal capacity of absorption and conductivity as accumulated during
the plenty of sunlight in daytime and reradiating at night. Therefore, cities tend to
experience a comparatively higher air and land surface temperature with adjacent rural
areas. These thermal differences in aggregation with heat given off by urban house and
various human factors including transportation, industries, Greenhouse gases and
deforestation contribute to the increase in heat and develop UHI.
Owing to urban heat island, the cost of energy increases and quality of life is
drastically affected. With each degree increase in temperature, utilization of power
subsequently increases for cooling purposes. The level of atmospheric and land surface
temperature increases due to the subsequent increased electricity use for air conditioning.
The earth’s rising atmospheric and land surface temperature are the hot issue in today’s
world. Ultimately, the multi-source data and remotely sensed imagery facilitate the
process of estimating variation in temperature and micro-level urban climate. The
following sections of the study discuss the major causes of climatic change, along with
factors having influence on land surface temperature.
5.2.1. Rapid Growth of Population
The available facts and figures on human population indicate that the population
growth of Lahore was recorded and estimated from 1.13 million in 1951 to 9.55 million
in 2015 (GoP, 2015) as shown in Figure 5.2. The population density of Lahore has also
increased by this alarming growth from 641 to 5,569 persons/km2 from 1951 to 2015
respectively. The urban population of Lahore is 82% while remaining is rural (GoP,
2015). The mean annual growth rate of Lahore during 1951-61 was 4.3%, which declined
133
to 3.32% during 1981-98. The growth rate, however, is still higher when compared to
other major cities of the world (IMPL, 2007).
Figure 5.2: Population Growth of Lahore from 1951 to 2015
Source: GoP, 2000; GoP, 2015
Population density is directly proportional to the effects, generating heat as more
people will consume more energy leading to the emission of heat. Residential areas with
lower spatial distribution and higher density contribute to the factor influencing the
production of urban heat. It is also indicated as shown in the settlement density maps that
the areas with higher population density in the center of the city experience higher
temperature as compared to the areas in south towards rural areas away from the center of
the city have lower density as low heat island effects. The following scatter plot (Figure
5.3) is created for the comprehension of structure and distribution of correlated variables;
MAT and Population Growth.
Figure 5.3: Correlation between Population Growth and MAT of Lahore
Minallah, 2016
0
2
4
6
8
10
12
1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 2020
Pop
ula
tion
(M
illi
on
s)
Year District Urban
R² = 0.6842
y = 0.1369x + 24.05223
23.5
24
24.5
25
25.5
26
1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00
MA
T (
OC
)
Population (million)
134
The above mentioned scatter plot (Figure 5.3) of variables, population growth and
MAT, shows data sample points along with line rising from the bottom left to upper right,
representing the presence of significance correlation. Results have shown correlation
value of R2 0.68, indicating positive correlation between population growth and increase
of MAT of Lahore. The results obtained by Pearson correlation, significant degree of
correlation between growth of population and MAT of Lahore are shown in Table 5.1.
Using Pearson correlation coefficient, results were obtained, showing perfect positive
correlation between MAT and population change of Lahore. Results have shown in Table
5.1, Pearson correlation value 0.836, indicating strong positive correlations between
population growth and increase of MAT of Lahore at the significant percentage i.e. 95%
as measured by alpha value and P-value, which is not greater than 0.05.
Table 5.1: Pearson Correlation between Population Growth and MAT
Variable Analysis MAT Population
MAT
Pearson Correlation 1 0.836**
Sig. (1-tailed) - 0.005
N 66 8
Population
Pearson Correlation 0.836** 1
Sig. (1-tailed) 0.005 -
N 8 8
**. Correlation is significant at the 0.01 level (1-tailed).
Minallah, 2016
5.2.2. Land use Changes
The influence of land use is considered to be an important driver in climate
change. The change detection analysis of land use has become vital element in the current
policies for monitoring and supervision of environmental amendments. The influence of
land use on temperature has been detected widely after 1980’s, by using satellite remotely
sensed data. The expansion of urban area is evident in the classified images from the
period 1973 to 2015. In the same vein, the population explosion decreased the agricultural
land and vegetation. It can be observed from the results that the agricultural
land/vegetation is declining in the City Centre as a result of new settlements. The various
land use types are identified in the satellite images in the Table 5.2 given below.
135
Table 5.2: Land use Patterns of Lahore form 1973 to 2015
Year Land uses Total Area
(Km2) Built-up Area Vacant Land Agriculture Water
1973 Area Km2 223.96 320.02 1213.23 14.79 1772
% 12.64 18.06 68.47 0.83 100
1980 Area Km2 273.29 305.44 1170.57 22.70 1772
% 15.42 17.24 66.06 1.28 100
1990 Area Km2 352.75 277.74 1117.82 24.17 1772
% 19.91 15.67 63.08 1.36 100
2000 Area Km2 445.12 242.23 1062.25 22.40 1772
% 25.12 13.67 59.95 1.26 100
2010 Area Km2 517.43 230.69 1004.99 18.89 1772
% 29.20 13.02 56.72 1.07 100
2015 Area Km2 643.51 196.34 915.71 16.44 1772
% 36.32 11.08 51.68 0.93 100
Source: Computed from Landsat Images
Human encroachments are also one of the major reasons in modification of natural
system that forces environmental and climatic change at global, regional and local levels.
Lahore, like other mostly urbanized areas in the world, is experiencing socio-cultural and
economic transformations due to urbanization and population explosion and
interconnection of these anthropogenic factors. This is the reason Lahore is extending and
becoming economically strong and industrialized with massive increase in urban built-up
land. Spatio temporal changes of land use are visible all over Lahore. Table 5.2 indicates
that land use experienced a sea change since 1973 to 2015 as shown in Figure 5.4.
5.2.2.1. Urban Built-up Area
Urban expansion accompanying massive changes in its morphological
patterns has been a factor in temporal and spatial land use change, at global, regional and
local level. Land use alteration indicates the patterns of developments of the city in terms
of reduction of agricultural land and loss of vegetal cover, expansion in urbanized
housing schemes and construction of sky scrapers, parking lots and increased density of
population. Spatio-temporal urban expansion is actually transformation of agricultural
136
and vacant land into impervious surfaces that can be detected in the land use classification
of Lahore from 1973 to 2015.
Figure 5.4: Land use Patterns of Lahore from 1973 to 2015
Minallah, 2016
137
The population of Lahore in 1972 was 2.17 million, which increased to 9.5 million
in 2015 with an increase of 350% in forty three years. Increasing demand of residential
areas with the growing population had risen due to urban expansion. In 1973, the urban
built-up land of Lahore was 223.96 km2, which increased in 2015 to 643.51 km2 as shown
in Table 5.2 and Figure 5.4.
Figure 5.5: Population and Urban built-up area of Lahore from 1973 to 2015
Minallah, 2016
Owing to the rapid growth of population and land use changes, the local climate
of Lahore had adverse effects. The ever increasing demand of the buildings for residential
and commercial purposes has led to expansion of the city in all the directions, particularly
towards south and southeast of Lahore city. Statistical data of the built-up area is acquired
through image classification. The following results were deducted in finding the
magnitude of change in urbanization and its impact on MAT.
Figure 5.6: Correlation between Urban built-up area and MAT of Lahore
Minallah, 2016
0
2
4
6
8
10
12
1973 1981 1990 2000 2010 2015
0
100
200
300
400
500
600
700
Pop
ula
tion
(m
illi
n)
Urb
an
bu
ilt-
up
are
a (
Km
2)
Urbanized Land Population
R² = 0.9333
y = 0.0039x + 23.40823
23.5
24
24.5
25
25.5
26
200 250 300 350 400 450 500 550 600
MA
T (
OC
)
Urban built-up area (Km2)
138
The results obtained by Pearson correlation in Table 5.3 is 0.870 which shows
ideal positive correlation between MAT increase and urban built-up land at the significant
rate of 95%, as obtained by alpha value and P-value which is not more than 0.05. The
results also highlight value of R2 which was 0.933 (Figure 5.6) indicating very strong
positive relationship between built-up area and MAT of Lahore. The results demonstrate
that the relationship between urban expansion and MAT is significant.
Table 5.3: Pearson Correlation between Built-up Area and increase of MAT Variable Analysis MAT Built-up Area
MAT Pearson Correlation 1 0.870*
Sig. (1-tailed) 0.012
N 66 6
Built-up Area Pearson Correlation 0.870* 1
Sig. (1-tailed) 0.012
N 6 6
*. Correlation is significant at the 0.05 level (1-tailed).
Minallah, 2016
5.2.2.2. Reduction in Agricultural Land
The massive, unplanned urban development created environmental disturbances
that is vulnerable and sensitive to the reduction of agricultural land and vegetation cover
transformed into the impervious surfaces which affect the temperature of Lahore and
create urban heat island phenomenon. During the last 6 decades, agricultural land has
been replaced majorly by impervious surfaces and increased built-up areas that have
affected the land surface temperature and redistribution of isolation.
The regression analysis between reduction in Agricultural land, loss of vegetation
and MAT of Lahore indicate negative correlations. The results show value of R2 is 0.728
(Figure 5.7) and indicate negative correlation between vegetation cover and increase of
MAT of Lahore.
The results shown in Table 5.4 with Pearson correlation value of -0.929 indicate
high negative correlations exist between the reduction in vegetation/agricultural land and
MAT of Lahore at a significant 95% as given value of alpha and P-value is not greater
than 0.05.
139
Figure 5.7: Correlation between Reduction in Agriculture Land and MAT of Lahore
Minallah, 2016
Table 5.4: Pearson Correlation between Reduction in Vegetation and MAT
Variable Analysis MAT Vegetation
MAT Pearson Correlation 1 -.929**
Sig. (1-tailed) 0.001
N 66 7
Vegetation Pearson Correlation -0.929** 1
Sig. (1-tailed) 0.001
N 7 7
**. Correlation is significant at the 0.01 level (1-tailed).
Minallah, 2016
5.2.3. Increase in Registered Factories
The installation of industrial units has been ever increasing since 1990 -2015, but
a massive increase can be noted after 2005 as shown in Figure 5.8. This increasing
number of heavy industries and factory units also contributed to considerable increase in
the temperature of Lahore. The relation of the rise in temperature corresponding with the
number of industrial units is quantified by regression analysis. The results have been
obtained with the help of bivariate correlation analysis. Table 5.5 shows the results for
Lahore in order to indicate the correlation between MAT increase and industrialization.
R² = 0.728
y = -0.0035x + 28.678
23
23.5
24
24.5
25
25.5
26
900 950 1000 1050 1100 1150 1200 1250
MA
T (
OC
)
Agriculture Land
140
Figure 5.8: Number of Registered Factories in Lahore from 1990 to 2015
Source: GoP, 2015
Figure 5.9: Relationship between MAT and Registered Factories in Lahore
Minallah, 2016
Table 5.5: Pearson Correlation analysis between MAT and Factories in Lahore
Variable Analysis MAT Factories
MAT
Pearson Correlation 1 .954**
Sig. (1-tailed) .006
N 5 5
Factories
Pearson Correlation .954** 1
Sig. (1-tailed) .006
N 5 5
**. Correlation is significant at the 0.01 level (1-tailed).
Minallah, 2106
500
700
900
1100
1300
1500
1700
1900
2100
2300
2500
199
0
199
1
199
2
199
3
199
4
199
5
199
6
199
7
199
8
199
9
200
0
200
1
200
2
200
3
200
4
200
5
200
6
200
7
200
8
200
9
201
0
201
1
201
2
201
3
201
4
201
5
No.
of
Fact
ori
es
Year
R² = 0.910424.2
24.4
24.6
24.8
25
25.2
25.4
25.6
25.8
800 1000 1200 1400 1600 1800 2000 2200 2400
MA
T (O
C)
No. of Registered Factories
141
The result obtained by Pearson correlation is 0.95. A positive correlation between
the MAT increase and number of factories at a significant level of 95%, while P-value is
not greater than 0.05 was recorded. R2 is obtained to be 0.910 (Figure 5.9), indicating the
positive correlation between the MAT and factories of Lahore.
5.2.4. Increase in Registered Vehicles
The ever increasing number of registered vehicles is one of the major factors
responsible for changing climate of Lahore. The number of vehicles registered in the
period from 1990-2015 was obtained from the Excise and Taxation Office, Govt. of the
Punjab, Lahore. The increase in the number of registered vehicles is displayed in Figure
5.10. A comparison between the number of vehicles registered during different periods
supports the argument that the increase in number of vehicles is causing climatic change
in Lahore. The number of vehicles registered during 1990-2000, 2000-2010 and 2010-
2015 indicate a difference of 80000 vehicles from 1990-2015. The result is significant in
making comparison for the city of Lahore, comprising an area of 400 km2.
Figure 5.10: Number of Registered Vehicles of Lahore from 1990 to 2015
Source: Excise and Taxation office Lahore, Pakistan, 2015
According to the data received from Excise and Taxation Department Lahore, the
total number of registered vehicles in the city was 0.5 million in 1998, 1.2 million in 2005
and 3.5 million in 2007. The number of vehicles is getting multiplied in five to seven
years as there is no existing Master Plan of the infrastructure of the city, except
maintenance, remodeling, construction of underpasses and flyovers, and mega structures
of impervious structure like Metro Bus and Orange Train Track.
0
500000
1000000
1500000
2000000
2500000
3000000
3500000
199
0
199
1
199
2
199
3
199
4
199
5
199
6
199
7
199
8
199
9
200
0
200
1
200
2
200
3
200
4
200
5
200
6
200
7
200
8
200
9
201
0
201
1
201
2
201
3
201
4
201
5
Veh
icle
s
Year
142
Figure 5.11: Trends of Vehicles of Lahore from 1990 to 2015
Source: Excise and Taxation office Lahore, Pakistan, 2015
According to the Lahore Motor Registration Authority, 238,790 vehicles were
registered in the year 2007, while 290,919 vehicles were registered in 2011, showing 18
% increase. The increased number of vehicles in the city is causing threat to the
environment by emitting poisonous gases including carbon mono oxide, carbon dioxide,
unburned gases and smoke in the air. Utilizing bivariate correlation, the correlation
between increasing number of registered vehicles and increase in MAT for Lahore is
shown in Table 5.6.
Figure 5.12: Relationship between Vehicles and MAT of Lahore
Minallah, 2016
249335
723381
2387993
3287987
0
500000
1000000
1500000
2000000
2500000
3000000
3500000
1990 2000 2010 2015
Reg
iste
red
Veh
icle
s
Year
R² = 0.861324.2
24.4
24.6
24.8
25
25.2
25.4
25.6
25.8
0 500000 1000000 1500000 2000000 2500000 3000000 3500000
MA
T (
OC
)
No. of Registered Vehicles
143
Table 5.6: Pearson correlation between registered Vehicles and MAT of Lahore
Variable Analysis MAT Vehicles
MAT
Pearson Correlation 1 .928**
Sig. (1-tailed) - .004
N 6 6
Vehicles
Pearson Correlation .928** 1
Sig. (1-tailed) .004 -
N 6 6
**. Correlation is significant at the 0.01 level (1-tailed).
Minallah, 2016
The tabulated figures show that the Pearson correlation is 0.92 (Table 5.6),
indicating positive correlation between the MAT and increasing number of vehicles per
year with P-value is greater than 0.05 and overall significance level is 95%. R2 is found to
be 0.86 (Figure 5.12), indicating the positive correlation between the Vehicles and MAT
of Lahore.
5.2.5. Increase in Greenhouse Gases
The Earth possesses natural greenhouse effects where sunlight is allowed to enter
into the atmosphere but the heat radiations are absorbed. Since the time of industrial
revolution, anthropogenic activities have also increased the ratio of GHGs in the air. The
ingredients of the greenhouse gases include Carbon dioxide (CO2) that occupies only a
small portion (0.03%) of atmosphere as the most important greenhouse gas. The recent
climatic change is also contributed by the carbon dioxide in the greenhouse gas. Carbon
dioxide is naturally released into the atmosphere by volcanic eruptions, animal respiration
and human activities concerning combustion of fossil fuels for energy and deforestation.
CO2 sustains for a considerable period in atmosphere and increases its effects. CO2
concentration has increased up to 30% since the industrial revolution. The second major
component in greenhouse gases is Methane (CH4). It is produced by natural and human
activities. The most considerable source of Methane is decomposition of organic matter
related to landfills and agriculture activities. Another contributing source is digestion of
ruminants of cattle etc. Methane as greenhouse gas is much stronger as compared to CO2
as it absorbs more heat, even if it is less in ratio in the atmosphere.
144
Nitrous oxide (NOx) is another strong greenhouse gas that is produced by
agricultural sector, significantly in the use of organic fertilizer. Nitrous oxide is also
produced in the air while burning fossil fuels. Chlorofluorocarbons (CFCs) are man-made
compounds specifically used for industrial use, in air-conditioners and in refrigerators.
The use of Chlorofluorocarbons has been regulated for the adverse effect concerning the
ozone layer under the Montreal Protocol. The industrial activity in the 20 th century grew
up to 40-fold, with greenhouse gases emission to be 10-fold. Ozone (O3) is also a potent
greenhouse gas which has a short life span in the atmosphere. Chemical reactions are the
main source of letting ozone emit volatile organic compounds from industrial plants,
power plants, automobiles and other commercial sources, including nitrogen oxides.
Besides the issue of trapping heat, the pollutant ground-level of ozone creates health
problems including respiratory system. It also causes damage to the ecosystem and crops.
An increase in the atmospheric CO2 concentration has been recorded to be 40 %
since it was recorded in pre-industrial era. It was indicated to be 280 parts per million
(ppm) by volume in 2010, while increase up to 396 parts per million (ppm) by volume
was noted in 2013. For the first time in the history, the monthly average concentration at
Mauna Loa rose up to 400 parts per million (ppm) by volume in 2014. The current ratio
of CO2 in atmosphere is higher as compared to the ratio recorded in at least 800,000
years. From 1850 till the end of the 20th century, the overall warming was recorded to be
2.5W/m2. CO2 contributes about 60% of the total figure and 25% of the contribution is
made by CH4. The remainder is provided by NO2 and halocarbons. This factor has
resulted in an increase of Earth’s average temperature from 15.5°C to 16.2°C in the last
one century. The level of warming effects resulting from the double quantity of CO2 in
the atmosphere from pre-industrial level is estimated to be 4W/m2.
LST is increasing owing to the increased ratio of these greenhouse gases that
retain more heat in the atmosphere. This increase in LST is also bringing about other
effects in climatic change. All these affects are termed as anthropogenic climatic change.
Most interestingly, certain ratio of GHGs is necessary to maintain human and animal life
because these gases absorb heat and maintain average temperature on Earth surface
around 14°C. If the greenhouse effects become nonexistent, life would freeze as average
temperature of earth would fall down to -19°C (WMO, 2016). Besides the beneficial side
145
of greenhouse effects, the excessive ratio in Lahore is polluting its environment day by
day.
Figure 5.13: Greenhouse gases from 2008 to 2010 in Lahore
Source: EPA, 2015
Since the demand of the energy in the urban areas is rising, the emission is also
rising, resulting in air pollution with increased quantity of Sulfur dioxide (SO2), Carbon
dioxide, Nitrogen oxide (NOx), carbon monoxide CO, and particulate matter (PM)
released. All the factors contributing to the release of the matter in the atmosphere cause
problems for human respiration and increase air and surface temperature. The appendix 2
indicates that most of the gases are above the quality standards of national environment.
A correlation analysis indicates a positive relationship in the results between urban
density and the air pollutants in increased urban temperatures.
The air quality samples are taken from the different locations of the Lahore city as
these urban built-up areas are associated with population density and high land surface
temperature. By applying the statistical test on the obtained data of Landsat image
analysis, it has been detected that the massive increase in urban growth is the main cause
of change in temperature of Lahore. It is also considered to be the major factor
contributing to increased greenhouse gases that led to smog formulation. The smog
appears as a dense layer of clouds of suspended-particles over Lahore. This dense layer of
2008 2009 2010
0
20
40
60
80
100
120
140
Am
ou
nt
ug
/m3
NO
NO2
NOx
CO
SO2
O3
PM 2.5
146
suspended particles matters (PM) in the atmosphere is triggering rise in minimum
temperature of Lahore.
5.3. Comparison of Contributing Factors of Changing Temperature
Trends
The following section, in detail, discusses the analysis of comparative aspects of
chosen contributing factors in temperature change of Lahore in a designated time period.
They are:
Population Growth of Lahore
Change of Land use Patterns
o Urban Built-up area
o Agricultural Land
Increase in Number of Registered Factories
Increase in Number of Registered Vehicles
Increase in Greenhouse Gases
The results acquired by Pearson correlation coefficient, are shown in Table 5.7,
which is presenting significant degree of correlation between urban expansion factors i.e.
growth of population, land use changes (i.e. urban built-up area and agricultural land),
increased industrial activities, increased registered vehicles, and greenhouse gases and
increase MAT of Lahore from 1950 to 2015.
Table 5.7: Degree of Correlation of Different drivers behind the Changing
Temperature Trends
Contributing Factors Degree of
Correlation
Type of
Correlation
Population Growth 0.83 Positive
Land
uses
Urban Built-up area 0.87 Positive
Agricultural land -0.92 Negative
Increase Number of Registered Factories 0.95 Positive
Increase Number of Registered Vehicles 0.92 Positive
147
According to the Table 5.7 and Figure 5.14, it can be concluded that the reduction
in agricultural land and growth of urban population and built-up areas are the major
factors among all in exercising effects on temperature of Lahore. The rate of increase of
urban built up area is similar to the reduction in agricultural land.
Figure 5.14: Comparison showing all Contributing Factors of Temperature Change
Minallah, 2016
5.3.1. Multiple Regression Analysis
The multiple regression model needs to be fitted to assess the relative importance
of different covariates. There is a strong correlation among the variables that play their
respective roles, each indicating indispensable for one another in the multi regression
model. In the Table 5.8, the results of multiple regression analysis indicate that these
variables have a strong impact on temperature of Lahore. The independent variables of
vehicle, population growth, factories and built-up area had a positive correlation with
temperature. Factory growth and vehicle registrations have correlated population increase
and increase of built up area which caused increase in the temperature of Lahore. The
agricultural land had negative correlation with the temperature of Lahore. As the
agricultural areas reduced due to the loss of vegetation cover, it caused an increase in the
temperature of Lahore. The R2 described that these variables had a strong impact on
temperature. The R2 showed direct variation in the dependent variables because of
independent variables.
-1.5
-1
-0.5
0
0.5
1
1.5
Population Built-up Land Agricultural land Factories Vehicles
Deg
ree
of
Corr
elati
on
148
Table 5.8: Multiple Regression Analysis
Dependent Variable: Temperature
Method: Least Squares
Date: 11/17/16 Time: 07:32
Sample: 1951 to 2015
Included observations: 8
Variable Coefficient Std. Error t-Statistic Prob.
C 36.08774 14.15207 2.549997 0.1255
Vehicles 6.24E-07 4.91E-07 1.270813 0.3316
Population Growth 4.82E-08 8.86E-07 0.054438 0.9615
Factories 0.001872 0.004024 0.465161 0.6875
Built-up Area 0.000552 0.011500 0.047979 0.9661
Agriculture land -0.008686 0.009323 -0.931633 0.4499
R-squared 0.963461 Mean dependent var 24.79250
Adjusted R-squared 0.872113 S.D. dependent var 1.054335
S.E. of regression 0.377044 Akaike info criterion 1.000794
Sum squared resid 0.284324 Schwarz criterion 1.060375
Log likelihood 1.996825 F-statistic 10.54717
Durbin-Watson stat 2.728306 Prob (F-statistic) 0.088860
5.4. Atmospheric Temperature Trends of Lahore from 1950 to 2015
The urban climate of Lahore has mainly been affected by the large scale
urbanization. In addition to the global impact being exercised on the climate change,
indigenous factors also contribute to the climate change. The temperature trends of the
city demonstrate variations in different years. The temperature change throughout the
period of analysis is not constant. After 1980s, the rising temperature trend shows
consistency and regularity. The analyzed parameters of temperature, MMiT change
pattern is regular and steady throughout the study span. During 1950-2015, an increase is
observed up to 1.38°C in MMiT of Lahore (Fig. 5.15a). Maximum change in MMiT
during 1988-2015 is observed (Fig. 5.15a). MMxT shows less significance in the change
trends. During the period of 1950-2015, a decrease is observed in the change trends of
MMxT; 0.47°C (Fig. 5.15b).
The main increasing trend in MMxT is observed during the period of 1957-1987
(Fig. 5.15b). The rapid increase in MMiT affected the MAT of Lahore. MAT has also
gradually risen from the period 1950 to 2015. MAT increase for the last 65 years has been
observed to be 0.377°C (Fig. 5.15c). Post 1980s is significant for the massive sprawl in
Lahore. For the time span from 1980s to date, climate of Lahore has also been badly
affected by the urban population. During the most urbanized period, the intensity of the
149
temperature is recorded to be almost 93% of the total rise in MAT after 1950. The
prediction signifying further growth is also computed on the basis of currently analyzed
data. If the same patterns in the temperature trend persist, the future increase in
temperature until 2030 is predicted to be 0.658°C.
Figure 5.15: Atmospheric Temperature Variations of Lahore from 1950 to 2015
y = 0.0389x + 16.976
R² = 0.6156
16
17
18
19
20
21
195
0
195
2
195
4
195
6
195
8
196
0
196
2
196
4
196
6
196
8
197
0
197
2
197
4
197
6
197
8
198
0
198
2
198
4
198
6
198
8
199
0
199
2
199
4
199
6
199
8
200
0
200
2
200
4
200
6
200
8
201
0
201
2
201
4
Tem
per
atu
re (
oC
)
(a) Lahore MMiT
Lahore (PBO) Urban Linear (Lahore (PBO) Urban )
y = -0.0134x + 31.253
R² = 0.1358
28
29
30
31
32
33
195
0
195
2
195
4
195
6
195
8
196
0
196
2
196
4
196
6
196
8
197
0
197
2
197
4
197
6
197
8
198
0
198
2
198
4
198
6
198
8
199
0
199
2
199
4
199
6
199
8
200
0
200
2
200
4
200
6
200
8
201
0
201
2
201
4
Tem
per
atu
re (
oC
)
(b) Lahore MMxT
Lahore (PBO) Urban Linear (Lahore (PBO) Urban )
150
Source: PMD, 2016
Figure 5.16: Trend line showing the future prediction of MAT of Lahore until 2030
Source: PMD, 2016
5.5. Land Surface Temperature Variations of Lahore, 1990-2015
The spatial variations of land surface temperature are essential to the study of
urban climate change. This section of analysis pursues to estimate Spatio-temporal trends
of land surface temperature variation of Lahore from 1990 to 2015 through Satellite
Remote Sensing thermal images. Figures 5.17 to 5.20 indicate the spatial variations
observed in LST in the urban area of Lahore and point out hotspots of heat. The results
depict that temperature has revealed a considerable change from 1990 to 2015 and it
corresponds to land use changes and urban expansion. A comparison of land surface
temperature variations is presented with the help of two selected years 1990 and 2015.
y = 0.0128x + 24.116
R² = 0.1861
23
24
25
26
27
195
0
195
2
195
4
195
6
195
8
196
0
196
2
196
4
196
6
196
8
197
0
197
2
197
4
197
6
197
8
198
0
198
2
198
4
198
6
198
8
199
0
199
2
199
4
199
6
199
8
200
0
200
2
200
4
200
6
200
8
201
0
201
2
201
4
Tem
per
atu
re (
oC
)
(c) Lahore MAT
Lahore (PBO) Urban Linear (Lahore (PBO) Urban )
y = 0.0128x - 0.8478
R² = 0.1861
23
23.5
24
24.5
25
25.5
26
1950 1960 1970 1980 1990 2000 2010 2020 2030
Tem
pera
ture
(O
C)
Year
Note: Trend line is drawn on the basis of moving of every ten years from 1950 to 2015
151
The section also describes the thermal zones within Lahore. Assessment of two Land
surface temperature variation maps (Figure 5.17 and 5.20) setting show modification of
the land use from agricultural land/vegetation use to the built-up area which always plays
a dynamic role in fluctuating temperature trends.
It is obvious by interpreting the thermal maps that the vegetation cover and water
bodies’ area have low temperature effects as heat sink or absorber. It is observed in
calculated results that the urban land use and density change have strong impact on the
changing trends of land surface temperature of Lahore. The points of both heat absorption
and heat emission clearly reflect rise in land surface temperature throughout Lahore i.e.
the River Ravi, walled city of Lahore and industrialized areas and vacant land
respectively. In the present study, land surface temperature of Lahore was assessed
through Radiative Transfer Method and the outcomes of the study are shown in the Table
5.9 and 5.10. The result shows that LST is strongly correlated to urban expansion, i.e.
land surface temperature increases with rapid increase in urban expansion.
Table 5.9: Descriptive Statistics of Land Surface Temperature of Lahore, 1990-2015 Image Acquired Min Temp (°C) Max Temp (°C) Mean Temperature (°C)
16-03-1990 16.5149 30.7528 23.6338
19-03-2000 16.9988 30.9987 23.9987
07-03-2010 17.2123 31.5668 24.3895
21-03-2015 17.4071 33.8357 25.6214
Source: Computed from Landsat Thermal Images
Table 5.10: Temperature Change from 1990 to 2015 Temperature (°C ) Change
Temperature 1990-2000 2000-2010 2010-2015 1990-2015
Maximum 0.2459 0.5681 2.2689 3.0829
Minimum 0.4839 0.2135 0.1948 0.8922
Mean 0.3649 0.3908 1.2319 1.9876
Source: Computed from Table 5.8
Temperature observations at MET observatories are measured at only small
number of places in a city, therefore, they are not reliable for acquisition of temperature at
all desired sites. The RS technique provides spatial data for all required locations. The
estimated LST maps illustrate temperature variations in Lahore as shown in Figure 5.17
152
to 5.20. The retrieved degree Celsius (°C) land surface temperature of Lahore is the
highest in 2015, based on the satellite image analysis derived results. The maximum
temperature was noted to be 33.83°C, according to the LST maps (Figure 5.20), while
minimum reaching temperature was 17.41°C in March, 2015. The increase in surface
temperature is attributed to the heat wave that is recurrent in such summer months. These
heat waves are found in the summer season for a few days.
The statistical data of estimated temperature of the year 1990 shows that the
minimum surface temperature recorded was 16.51°C while the maximum temperature
recorded was 30.75°C. The mean temperature was 23.63°C in 1990. It is reflected in the
Figure 5.17 that the urban built-up area, vacant land and industrial areas exhibited have a
high temperature while agricultural land, vegetation and water bolides show lower
temperature comparatively. The ‘hotspots’ are easily recognizable in the LST distribution
map (Fig. 5.17). The center of the city (around walled city) and industrial area and vacant
lands are found to be the most extensive hot spots. The difference of the temperature in
hot spots is reflected not only in the state of vegetation cover, solar illumination and
atmospheric influences, but also variation in land use type.
Figure 5.17: Land Surface Temperature Variations of Lahore in 1990
Minallah, 2016
153
Figure 5.18 reflects the increase in the mean land surface temperature from
23.63°C in 1990 to 23.99°C in 2000. The increase in temperature of the study period,
from 1990 to 2000 is noted to be 0.39°C as described in Table 5.10. The increase in
population of Lahore has led to massive replacement of natural resources with impervious
surfaces such as bridges, roads, parking lots, buildings, pavements and other concrete
structures. The population increase is noted to be 4 million in 1990 which shot to 6
million in 2000. These heat islands are capable of retaining heat in the sun light and
omitting it at night, causing stress to the environment and affecting the urban micro-
climate of Lahore.
The mean temperature of the year 2000 was 23.99°C, as shown in Table 5.9,
signifying that the land surfaces experience a little difference in LST during the
mentioned periods 1990-2000. The maximum LST in the year 2000 was 30.99°C and
minimum LST recorded in 2000 was 16.99°C. The central area of Lahore can be easily
differentiated from the peripheries. The central area showed the temperature of 29°C,
while the temperature of the outskirts is lower, i.e. 16 to 27°C. The urban built-up areas
of Lahore have expanded eastwards and southwards.
Figure 5.18: Land Surface Temperature Variations of Lahore in 2000
Minallah, 2016
154
Figure 5.19 reflects the spatial variation of temperature of Lahore for the year
2010. The LST ranged from 17.21°C to 31.57°C with a mean temperature of 22.38°C.
The ground thermal pitches in the center of Lahore, comprising buildings, parking lots,
houses, cement pavements and infrastructure were particularly concentrated and
determined. The population density in the center of Lahore was greater, along with the
anthropogenic activities which were much more than ever before. Resultantly, the higher
surface temperature was recorded in Lahore.
Owing to the commercial activities and industrial consumption in the industrial
areas, the highest land surface temperature is measured. The Figure (5.19) shows the east,
southeast and south parts of Lahore exhibit the high temperature due to the vacant and
built-up land. The effects of the vegetation cover can be noted in the areas showing
lowest LST values over densely vegetation cover and agricultural land. The extreme
temperature detected in the built up, vacant land and industrial areas ranges from 27°C to
31.56°C.
Figure 5.19: Land Surface Temperature Variations of Lahore in 2010
Minallah, 2016
In response to the building geometry in the urban areas, the circulation of the wind
is limited. These environmental conditions lead to human discomfort and require air
155
conditioning. Moreover, air conditioners and electric generators are used in urban areas,
causing more heat and increasing temperature. However, in the rural and the suburban
areas, the heat is lower owing to the vegetation cover and agricultural land still in use.
Changes of LST in urban and rural were significant in causing notable urban heat island
effects. Figure 5.20 demonstrates the Spatio-temporal distribution of emissivity-corrected
LST of Lahore in 2015.
The readings of the land surface temperature for the year 2015 show that the
highest temperature is 33.83°C and the lowest temperature is 17.40°C. The mean
temperature is 25.62°C. Higher land surface temperatures mainly increase in industrial
zones and urban centers, that is, the UHI effects. After identifying the land surface
temperature variation maps, it was indicated that the maximum land surface temperature
values existed mostly in the center of the city, also known as walled city, featured by
densely built-up area, commercial centers and deep street canyons. The maximum
temperatures in the urban and the suburban areas experienced land surface temperature
within 28°C to 33°C. The LST observed in the River Ravi, water channels, canals, along
with green spaces was lowest surface temperature.
Figure 5.20: Land Surface Temperature Variations of Lahore in 2015
Minallah, 2016
156
The mean land surface temperature in 2015 was noted to be 25.62°C as compared
to the temperature of initial reference period of 1990, i.e. 23.68°C. The maximum
temperature of 33.83°C and the minimum temperature of 17.40°C was estimated for 2015
which was also higher than the initial reference period of 1990, i.e. 30.75°C maximum
and 16.51°C minimum surface temperature. The comparison of both the periods proves a
definite increase in temperature as shown in Table 5.8 and 5.9. The Spatio-temporal
distribution of emissivity-corrected temperature, ranging from the period of 1990 to 2015
of Lahore is shown in Figure 5.17 to 5.20.
5.6. Town wise Trends of LST of Lahore between 1990 and 2015
The method of digital remote sensing provides a spatial extent of surface urban
heat island (SUHI) effects, along with magnitude of hotness of whole of the city. Figure
5.17 and 5.20, reflect that the distribution of the impervious surfaces (IS) is directly
associated with the higher temperature. The LST town wise comparative study (Figure
5.21a & b) for the year 1990 and 2015 reflects the higher land surface temperature with
the extension of development going-on in the urban regions. Some of the hot spots in the
entire study region boast heat islands effects. According to Town wise LST map, high
temperature areas are Shalamar Town, Data Ganj Baksh Town, Gulbarg Town, Ravi
Town, Nishtar Town, Iqbal Town, and Saman Abad Town as Shown in Figure 5.21a.
The map of LST 1990 in Figure 5.17 indicates that the most widespread hot spot
is found in the urban built-up, industrial zone and bare soil located in the west and the
south of the city. On the other hand town wise LST map of March 1990, as shown in
Figure 5.21a, exhibits that low land surface temperature areas are Samanabad Town,
Wagha Town, Cantonment and Aziz Bhatti Town of Lahore. For comparison, LST is also
assessed for March 2015 as shown in Figure 5.20. According to the estimation, 1.98°C
(Table 5.10) LST has increased in last 25 years. It is observed that in Figure 5.21b
Shalamar Town, Data Ganj Baksh Town, Gulbarg Town, Ravi Town, Nishtar Town,
Iqbal Town, and Saman Abad Town were warmer in the year March 2015 than the year
March 1990. It is worth mentioning that in the area of Aziz Bhatti Town, Nishtar Town
and Wagha Town, there were no urbanization and development, therefore the lower
temperature was experienced in the year 1990. However the expansion of Lahore city in
these areas was urbanized and the temperature rose in 2015 as compared to 1990. In the
157
year 2015, the widespread hotspot was identified in the old city, industrial areas, airport
along with impervious runways and barren lands located in the east and southeast of the
city.
Figure 5.21: Town wise Comparison of LST of Lahore in 1990 and 2015
Minallah, 2016
158
Figure 5.22: Town wise Trends of LST of Lahore in 1990 and 2015
Minallha, 2016
The reduction of the diversity of species and damage to the eco-system can be
attributed to the conversion of natural vegetation and consumption of the cultivated land
into built-up land. The built-up areas comprise buildings, pavements, parking lots, roads
and respective infrastructure. All these building materials and concrete contribute towards
the increase in land surface temperature of Lahore. Similarly, transportation and the
combustion of the vehicles add to more air pollution, creating troubles for health issues
and contributing towards smog problem the number, of industries in Lahore has also been
a contributing factor in raising land surface temperature. The heat island effect is
prominent in industrial areas. The assessment of environmental condition and measures
for the policy making for the protection of the environment can be carried out by
considering the above mentioned factors.
5.7. The Correlation between LST and Urban Land use Patterns
The correlation between land use type and land surface temperature was examined
for further understanding of the influence of urban expansion and development on land
surface temperature variation of Lahore. The characteristics of the relationship between
temperature variations related with different types of land use are summarized in Table
5.11. The map in Figure 5.23 represents mean LST by altered land use type. It is evident
that the densely populated, built-up and industrial areas in the city are a factor of
temperature increase. The heat consumed by a human body along with the heat stored in
the impervious structures that absorb heat in the day time and release during the night
Aziz
Bhatti
Town
Data
Gunj
Baksh
Town
Gulber
g
Town
Iqbal
Town
Nishter
Town
Ravi
Town
Saman
abad
Town
Shalam
ar
Town
Wahga
Town
Canto
ment
Mean LST 1990 22.71 24.38 24.42 23.63 23.76 24.35 23.35 24.77 23.53 22.91
Mean LST 2015 25.41 25.17 27.85 25.62 25.69 25.78 25.31 25.57 26.14 27.25
0
5
10
15
20
25
30
LS
T (
°C)
159
time is also a contributing factor. The highest land surface and air temperature is always
found in the surroundings of urban built-up areas, open surfaces and industrial zones.
It indicates that the urban growth is contributing to the temperature raised by
substituting green cover with non-transpiring, non-evaporating surfaces of metal, stone,
asphalt and concrete. In contrast to that, the land under agricultural use, and growing
crops in the surrounding rural areas has cooler temperature as compared to the urban
environment. Areas under vegetation cover show much lower temperature in the last 25
years as the vegetation cover reduces the heat ratio stored in the surface and soil through
transpiration.
Table 5.11: Land Surface Temperature Variations with Different Land uses
Land uses
Year Built-up Area (LST) Vacant Land (LST) Agriculture (LST) Water (LST)
Min. Max. Mean Min. Max. Mean Min. Max. Mean Min. Max Mean
1990 18.78 29.11 23.19 19.68 30.75 23.16 18.78 27.03 21.10 16.51 28.28 20.78
2000 18.54 29.89 24.22 17.44 27.53 22.49 17.01 24.51 20.76 16.99 24.22 20.61
2010 19.95 30.03 24.99 18.80 30.57 24.68 18.20 24.61 21.41 17.22 22.03 19.62
2015 17.86 33.84 26.17 17.41 33.27 25.63 19.12 31.60 24.87 19.13 28.47 21.71
Source: Computed from Landsat Thermal Images
There is a dire need of studying the effects of land use on LST and understanding
the characteristics of thermal signature of different land uses. Figure 5.23 indicates the
average surface temperature by each land use type during the span from 1990 to 2015.
The variations in surface radiant temperature reflect the effects of different land use types
on urban thermal setting, as shown in the Figure 5.23. The Table 5.11, illustrates that the
patterns of the distinguishing temperature are related to the thermal physiognomies of the
each land use types. To comprehend the urban expansion impact on LST, the thermal
signature of different land use classes was acquired by land use map overlaid with a LST
map of the same year. The maximum and minimum and mean values of LST by type of
land use classes are indicated in the Table 5.11 and in Figure 5.23.
It is evident that the built-up or urban land exhibited the highest mean temperature
(23°C in 1990, 24°C in 2000, 24°C in 2010, and 26°C in 2015), followed by vacant land
(23°C in 1990, 22°C in 2000, 24°C in 2010 and 25°C in 2015) as shown in Figure 5.23.
This highlights that the urban expansion is associated with the rising temperature by
transforming natural vegetation cover and agricultural land with urban structure i.e. non-
160
evaporating, non-transpiring exteriors such as asphalt, metal, stone and concrete. The
standard deviations of hotness values are less in relation for both land use classes,
demonstrating that the surfaces of urban do not exhibit big differences in surface
temperature due to the non-evaporating, non-transpiration, dry nature of urban material.
Water bodies experience minimum lower temperature as compared to other land use
classes (19°C to 21°C). Table 5.11 indicates the statistics of the surface temperature,
followed by the agricultural land (21°C to 24°C). Henceforth, the water bodies and the
vegetation cover are cooler as compared to urban built-up and vacant land.
Figure 5.23: Land Surface Temperature Variations with Different Land uses
Minallah, 2016
161
In Table 5.11, the results of land surface radiant temperature indicate the
variations in land use classes. The temperature of the densely populated residential and
commercial areas exhibit maximum temperature, followed by the medium densely
populated area, vacant land, vegetation and park area. It is evident that the impervious
surfaces are warmer as compared to the vegetative covered areas. Urban and suburban
areas experience development in the south and south western side in low-cost residential
housing schemes. Moreover, the industrial zone and the highly built-up areas contribute
to concentration of the heat island. The standard deviation value of the LST is
comparatively lower for the urban cover indicating that there is no such wide variation in
the urban surfaces because of non-evaporative and non-transpiring materials.
The minimum land surface temperature in 1990 was detected in areas with water
bodies (River Ravi) followed by (16°C) thick vegetation covers (18°C). The pattern in
2015 showed contrast where the minimum temperature was found at water bodies (River
Ravi), 17°C, followed by natural vegetation cover 19°C. This difference is due to eroding
vegetation cover by the year 2015. This modification in temperature pattern is attributed
to the difference in the state of vegetative area, solar illumination, atmospheric influences
and satellite remotely sensed TM, ETM+ and OLI_TIRs dataset.
The data acquisition in the same season showed difference in the surface
temperature of the water bodies. There is considerably low temperature in thick
vegetation zones in 2015, as the dense vegetation cover reduces the intensity of heat
absorbed in soil through the natural process of transpiration. Crop lands have thin vegetal
cover and naked soil. Various factors like water content, vegetation and surface soil are
key to contribute to the difference observed in the surface radiant temperature values. The
relationship between the land surface temperatures, texture of the land cover, land use
changes, influence the land surface temperature of Lahore. GIS and remote sensing
techniques with image processing help in visualizing the land surface alterations by urban
expansion.
5.8. Correlation between LST and indices
5.8.1. Relationship of LST to NDVI
NDVI served as an indicator of vegetal profusion in the area and is then used to
measure land surface temperature. The areas with the highest vegetal cover showed low
162
LST as the area under vegetation cover determines the land surface temperature through
the process of evapotranspiration from surface to atmosphere by latent heat flux. The
correlation between the NDVI and LST is valuable for the understating of urban micro
climate. The urban green spaces add to moisture in the air and reduce the impact of heat
in the urban climate. The highest NDVI values were found in the south and southeast,
where vegetal cover and cropland are mostly located in the city of Lahore. The lowest
NDVI values were detected in the densely residential and built-up areas with less
vegetation cover.
Figure 5.24: Spatial Distribution of LST and NDVI of Lahore in1990
Minallah, 2016
The Spatio temporal distribution of LST and NDVI can be exemplified from the
Figure 5.24 to 5.27. Correlation analysis from Pixel to pixel was carried out to determine
the association between temperature and NDVI. It is demonstrated in the Table 5.12 that
land surface temperature tends to be strongly correlated with NDVI values in all kinds of
land use in the study span of 1990 to 2015. Figure 5.24 to 5.27 indicate the LST values to
be strongly negatively correlated to NDVI. Through Spatio temporal maps of LST and
NDVI, it is demonstrated that the features in pixels in NDVI with high values have low
LST, while the regions with lowest NDVI values have higher LST values.
163
Figure 5.25: Spatial Distribution of LST and NDVI of Lahore in 2000
Minallah, 2016
Figure 5.26: Spatial Distribution of LST and NDVI of Lahore in 2010
Minallah, 2016
It also implies that the areas displaying lowest NDVI values have less vegetal
cover as a consequence of urban expansion, whereas the higher NDVI values have thick
164
vegetal cover, and therefore, temperature increases with the decrease in vegetal density.
In case of Lahore, a strong correlation is observed between LST and NDVI, which
ensures the prospect of using linear regression in predicting LST if the values of NDVI
are known.
Figure 5.27: Spatial Distribution of LST and NDVI in 2015
Minallah, 2016
Henceforth, accurate LST values can be predicted by using NDVI. It is observed
that the NDVI values have decreased from 1990 to 2015 due to urban expansion and
reduction of vegetal cover in the city of Lahore. Spatial distribution of NDVI is not only a
matter of influence of reduced green spaces, rather can also be attributed to availability of
solar radiation, topography and other factors. NDVI is generally utilized in measuring
Land Surface Greenness (LSG), established on the postulation that values of NDVI are
directly comparative to the area under vegetal cover in an image per pixel area. Table
5.12 indicates the relationship between LST and vegetation density.
Table 5.12: Relationship between Vegetation Density and LST
Year NDVI
Minimum
NDVI
Maximum
LST
Minimum
LST
Maximum
Correlation
(R2)
1990 -0.264706 0.664336 16.5149 30.7526 0.988
2000 -0.439494 0.766422 16.9988 30.9987 0.977
2010 -0.285714 0.732484 17.0471 31.5668 0.975
2015 -0.178791 0.590235 17.4071 33.8357 0.984
Minallah, 2016
165
Figure 5.28 with scattered plots indicates the relationship between LST and
NDVI. The regression line produced expressive explanation, showing strongly negative
correlation with LST. These values of correlation can easily be visualized by plotting LST
values for vegetation cover index. The consequences indicate that the thick vegetal
covered areas can reduce the effects of temperature and UHI. The strongly negative
correlation between the temperature and Normalized Difference Vegetation Index
specifies that the greater biomass of vegetation has lower LST. The NDVI and surface
radiance temperature have direct impact on changes in land use type. The values for four
periods of analysis showed that the NDVI and LST are correlated negatively at the
Pearson index, i.e. -0.994, -0.989, -0.988 and -0.992.
Figure 5.28 (a, b, c and d): Relationship between NDVI and LST form 1990 to 2015
y = -15.62x + 26.255
R² = 0.9888
15
17
19
21
23
25
27
29
31
33
-0.4 -0.2 0 0.2 0.4 0.6 0.8
LS
T 1
99
0
NDVI 1990
1990 ( a )
y = -11.68x + 24.953
R² = 0.9774
15
17
19
21
23
25
27
29
31
33
-0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
LS
T 2
00
0
NDVI 2000
2000 ( b )
166
Minallah, 2016
5.8.2. Relationship of LST to NDBI
Normalized Difference Built-up Index is materialized to extract built-up area from
urban land use and strengthen building information. The values of NDBI are related to
temperature to investigate the impact of built-up area on surface temperature. Positive
correlation in association between NDBI and temperature indicates that built-up area
increases surface temperature. The correlation between NBDI and surface temperature is
directly proportional to each other, regions higher in land surface temperature have high
density constructions as compared to the regions with no construction with lower
temperature. The level of urbanization and industrialization is reflected clearly in NDBI
index.
y = -14.056x + 26.606
R² = 0.9758
16
18
20
22
24
26
28
30
32
34
-0.4 -0.2 0 0.2 0.4 0.6 0.8
LS
T 2
01
0
NDVI 2010
2010 ( c )
y = -20.992x + 29.34
R² = 0.9841
15
17
19
21
23
25
27
29
31
33
35
-0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7
LS
T 2
01
5
NDVI 2015
2015 ( d )
167
Figure 5.29: Spatial Distribution of LST and NDBI of Lahore in 1990
Minallah, 2016
Figure 5.30: Spatial Distribution of LST and NDBI of Lahore in 2000
Minallah, 2016
It can be demonstrated in the analysis of four NDBI index maps as shown in
Figure 5.29 to 5.32, that highest NDBI is found in the inner circle of the city, indicated
with red highlighted background. These areas with highest NDBI values are airports,
168
industrial zones and residential areas in the city of Lahore. The River Ravi has the lowest
NDBI index.
Figure 5.31: Spatial Distribution of LST and NDBI of Lahore in 2010
Minallah, 2016
Figure 5.32: Spatial Distribution of LST and NDBI of Lahore in 2015
Minallah, 2016
169
The lowest NDBI recorded in 1990 was in small agricultural area towards the
south and south east of the city. In 2015, however, the lowest NDBI index was found in
cropland in the south and southwest of the city. The higher NDBI values were found in
the central area of Lahore, concentrated by sky scrapers and concrete surfaces, parking
lots and high building density and the lower NDBI values were recorded in the east and
southeast outskirts (Figure 5.29 to 5.32). Furthermore, graphs of the scatterplots were
prepared to discover the correlation concerning surface temperature and NDBI.
Meaningful explanations were yielded by regression model in which NDBI values were
positively related with LST (Figure 5.33).
Table 5.13: Relationship between Built-up area and LST
Year NDBI
Minimum
NDBI
Maximum
LST
Minimum
LST
Maximum
Correlation
(R2)
1990 -0.645161 0.414634 16.5149 30.7526 0.989
2000 -0.623188 0.441441 16.9988 30.9987 0.977
2010 -0.521127 0.492228 17.0471 31.5668 0.984
2015 -0.607582 0.751279 17.4071 33.8357 0.984
To examine the relationship between LST and NDBI, sample points were
randomly selected from land surface temperature and NDBI maps were utilized to
produce regression fitting and to estimate coefficient of Pearson correlation (Figure 5.33).
The values for four periods of analysis showed that the NDBI and LST are correlated
positively at the Pearson index, i.e. 0.995, 0.989, 0.992 and 0.992. NDBI was effeciently
used to characterize the changes in LST.
Figurer 5.33 (a, b, c and d): Relationship between NDBI and LST form 1990 to 2015
y = 13.681x + 24.72
R² = 0.989215
17
19
21
23
25
27
29
31
33
-0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6
LS
T 1
99
0
NDBI 1990
1990 ( a )
170
Minallah, 2016
y = 13.232x + 24.245
R² = 0.977315
17
19
21
23
25
27
29
31
33
-0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6
LS
T 2
00
0
NDBI 2000
2000 ( b )
y = 14.017x + 23.809
R² = 0.9843
15
17
19
21
23
25
27
29
31
33
-0.6 -0.4 -0.2 0 0.2 0.4 0.6
LS
T 2
01
0
NDBI 2010
2010 ( c )
y = 11.867x + 24.17
R² = 0.984215
17
19
21
23
25
27
29
31
33
35
-0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
LS
T 2
01
5
NDBI 2015
2015 ( d )
171
5.9. Cross Validation of Satellite and MET Station Data
Table 5.14 and 5.15 illustrate the cross authentication of LST of Lahore computed
from Landsat thermal images with Lahore urban and rural MET observatory data. The
statistical data of estimated LST of the year 1990 show that mean LST was 23.6°C while
the mean LST was 25.6°C in 2015. The mean LST increased by 2°C between the periods from
1990 to 2015. The atmospheric temperature data analysis show that mean atmospheric
temperature was 22.6°C while the mean atmospheric temperature was 23.4°C in 2015 at urban
MET station. The mean atmospheric temperature increased from 1990 to 2015 by 0.8°C in both
urban and rural Met stations. So both the data sources satellite and MET Station data,
confirm that the temperature of Lahore has increased Sfrom 1990 to 2015.
Table 5.14: Cross Validation of LST with Lahore Urban (PBO) MET Station Data
Date of
Acquisition
Acquisition Source
Satellite (LST) Urban (PBO)
Max (°C) Min (°C) Mean (°C) Max (°C) Min (°C) Mean (°C)
16-03-1990 30.7 16.5 23.6 27.9 17.3 22.6
19-03-2000 30.9 16.9 23.9 27.6 14.0 20.8
07-03-2010 31.5 17.0 24.3 25.5 15.6 20.6
21-03-2015 33.8 17.4 25.6 28.5 18.3 23.4
Table 5.15: Cross Validation of LST with Lahore Rural (APT) MET Stations Data
Date of
Acquisition
Acquisition Source
Satellite (LST) Rural (APT)
Max (°C) Min (°C) Mean (°C) Max (°C) Min (°C) Mean (°C)
16-03-1990 30.7 16.5 23.6 28.6 15.1 21.9
19-03-2000 30.9 16.9 23.9 27.5 15.6 21.6
07-03-2010 31.5 17.0 24.3 25.5 16.5 21
21-03-2015 33.8 17.4 25.6 27.7 17.7 22.7
Figure 5.34: Comparison between LST with Urban-Rural MET Stations Data
Source: Minallah, 2016; PMD, 2016
0
5
10
15
20
25
30
35
40
Max Min Max Min Max Min
LST (Satellite) Met. Urban (PBO) Met. Rural (APT)
Cels
ius
Deg
ree
16-03-1990 19-03-2000 7/3/2010 21-03-2015
172
The land surface temperature values obtained in this research from the thermal
images are likely to be a bit higher than the air temperature because of the roughness and
coarseness of the land apparent which exercises impact on the surface radiance
temperature. It is also noted in the present study that effective measurement of the land
surface temperature must confirm to the importance of the nature of apparent, its
unevenness on emissivity and then should be incorporated. The emissivity values should
be obtained for various land use types and incorporated for the estimation of land surface
radiant temperature.
5.10. Urban Heat Island of Lahore
An urban heat island formed in a cosmopolitan city experiences warmer
atmosphere as compared to its immediate rural vicinity. This is attributed to the
anthropogenic activities pursued in the urban areas. Urban landscape also experiences
changes due to developments including building, streets, roads and other infrastructure by
replacing the vegetation cover with impervious surfaces while the permeable surface with
moist becomes impermeable and dry. These land use changes contribute to urban areas
which become warmer as compared to the countryside, ultimately forming a heat island.
The process of evaporation of the water in plant cools the surrounding areas.
In Figure 5.35 (a & b), the minimum and maximum temperatures as change in the
air temperature on the annual basis are shown in the rural and urban MET observatories.
The regression results of annual air temperature are given in the Table 5.16 and 5.17,
showing the net change in minimum and maximum air heat for the time span of 1950-
2015. Both the countryside and urban MET observatories demonstrating the minimum
and maximum air temperature were indicating increase at different rates. It is significant
to acknowledge that the minimum temperature increased in the urban stations as
associated to the countryside stations.
On the other hand, the study period from 1950-2015 has no momentous variation
in the maximum temperature in either of the stations. In the given Table 5.16, it is
indicated that the highest temperature increase was observed and measured to be 1.38°C
in the urban station. The decrease in the minimum temperature at Lahore airport station,
is observed and measured to be -1.44°C. The decreasing trend in the minimum
temperature is also observed in airport station.
173
Table 5.16: dTmin and dTmax over the period of 65 years (1950-2015) at Lahore
urban station and Lahore airport rural station
Period dTmin/6.5 decades dTmax/6.5decades
Lahore (PBO) Lahore (APT) Lahore (PBO) Lahore (APT)
Annual 1.38 -1.44 -0.47 -1.75
Minallah, 2016
Table 5.17: Regression results of temperature of Lahore urban station and Lahore
airport rural station during 1950 to 2015
Period Minimum Temperature Maximum Temperature
Lahore (PBO) Lahore (APT) Lahore (PBO) Lahore (APT)
Annual
y = 0.0386x +
16.983
y = 0.002x +
17.382
y = -0.0135x +
31.256
y = 0.0013x +
30.469
R² = 0.6014 R² = 0.0044 R² = 0.1325 R² = 0.0016
Minallah, 2016
Figure 5.35(a) illustrates the analysis and variability of mean maximum air
temperature of both the stations (urban and rural). The graph of maximum temperature
change trends in the urban areas shows tendency of increase from 1950 to 1998,
especially the year 1998 which was declared to be the warmest year in the history. Before
1998, the difference in the annual mean maximum temperatures of both the stations (rural
and urban) was higher as compared to the trend of increasing temperature till 1998, at
urban station in particular. The period after 1998-2015, the mean maximum temperature
of urban station shows decreasing trend while mean maximum temperature of rural
station shows increasing trend.
The Figure 5.35(b) indicates that the time period from 1950-1967 experienced
almost same trend in temperature change at both the stations, but afterwards, the period
from 1968-1994, the trends seem to differ in minimum temperature in urban station as
compared to the rural station. The year 1995 onwards, the minimum temperature of
Lahore started increasing at a rapid pace as the city was the center of massive urban
development and anthropogenic activities. The Figure 5.35 (b) also highlights the effects
of urbanization on the urban temperature. An analogous proportion is observed in the
temperature trends of increase at urban station, owing to the population growth
throughout the study period. The increase in population growth keeps escalating the
minimum temperature which affects the mean annual temperature of Lahore.
174
Figure 5.35: The mean maximum & minimum temperature variations of Lahore at
Lahore Airport and Shadman observatories.
Source: PMD, 2016
The long-term urban heat island of Lahore as highlighted in Figure 5.36 shows the
trends of temperatures of the two MET stations (rural-urban) of Lahore. The urban site
MET station is situated at Shadman while the rural site at Lahore airport. The difference
in the air temperature (both minimum and maximum) of urban and rural, is observed to be
increased, owing to the effects exercised by urban heat island phenomenon (Figure 5.36).
The massive change in the urban growth and population explosion related with the land
use alteration contributed to the changing temperature of urban areas. The transformation
of the vegetal cover into built-up land use has higher impact on minimum and maximum
air temperature (Figure 5.35 (a & b)), changing the mean annual temperature of Lahore. It
is also noted that the urban sprawl and population growth increased the impervious
26
27
28
29
30
31
32
331
950
195
2
195
4
195
6
195
8
196
0
196
2
196
4
196
6
196
8
197
0
197
2
197
4
197
6
197
8
198
0
198
2
198
4
198
6
198
8
199
0
199
2
199
4
199
6
199
8
200
0
200
2
200
4
200
6
200
8
201
0
201
2
201
4
Tem
pera
ture
An
om
aly
(°C
)
(a) Annual Mean Max. Temperature
Lahore (APT) Rural Lahore (PBO) Urban
16
17
18
19
20
21
195
0
195
2
195
4
195
6
195
8
196
0
196
2
196
4
196
6
196
8
197
0
197
2
197
4
197
6
197
8
198
0
198
2
198
4
198
6
198
8
199
0
199
2
199
4
199
6
199
8
200
0
200
2
200
4
200
6
200
8
201
0
201
2
201
4Tem
pera
ture
An
om
aly
(°C
)
(b) Annual Mean Min. Temperature
Lahore (APT) Rural Lahore (PBO) Urban
175
surfaces, affecting the minimum temperature more as compared to the maximum
temperature.
Figure 5.36: Urban and rural site Temperature Trends to represent long term UHI
Source: PMD, 2016
The Figures 5.37 and 5.38 display the urban heat island and some hotspots of
temperature over Lahore. In the urban areas, the impervious surfaces preserve heat and
create urban heat island. Besides the impervious surfaces, some of the other factors also
affect the UHI. In large metropolises, the preservation of heat is higher than that of the
smaller cities. Fig 5.37 & 5.38 show the spatial variability of heat island of Lahore where
the densely built-up area, industrial area and the urban land use change demonstrate
higher heat island effects as compared to the country side. The Figures 5.37 and 5.38 also
highlight the maximum temperature of urban heat island in the industrial area,
commercial area, transport network and densely built-up areas.
It supports the fact that concentration of heat in urban area is due to the
impervious structure which affects the local climatic conditions. The distribution of
surface land temperature variations is presented in the Figures 5.37 and 5.38. It is due to
the vertical developments in the city entre and new developments are found at the
peripheries of the city. The original land cover has been destroyed by the new developing
sites that enhance LST.
21
21.5
22
22.5
23
23.5
24
24.5
25
25.5
26
195
01
952
195
41
956
195
81
960
196
21
964
196
61
968
197
01
972
197
41
976
197
81
980
198
21
984
198
61
988
199
01
992
199
41
996
199
82
000
200
22
004
200
62
008
201
02
012
201
4
Tem
pera
ture
An
om
ely
(0
C)
Lahore Urban- Rural MAT
Lahore (APT) Rural Lahore (PBO) Urban
176
Figure 5.37: Presence of Urban Heat Island in 1990
Minallah, 2016
Figure 5.38: Presence of Urban Heat Island in 2015
Minallah, 2016
177
The areas with higher land surface temperature values are identified to confirm the
contributing factors for developing heat island. It is observed that highest Land surface
temperature values are found in industrial areas, vacant lands, densely populated and
built-up areas. The higher land surface temperature at vacant lands can be recorded as
activities related to the development carried on in those areas. In the same vein, the urban
micro-climate is affected by the ongoing development activities in the new housing
schemes in the urban area. The direction of the expansion of the city is also identified in
the vacant lands which show higher temperature.
Research related to urban heat island has significant implications in terms of
health issues pertaining to human beings. The consequence of the heat island, especially
in the hot summer season, can have severe implications in climatic change, at night in
particular. Heat that emerges round the clock allows no respite for the inhabitant
including those, who do not intake much quantity of water at night to stay hydrated. The
facility of air conditioning is not available for everyone in the underdeveloped countries
and poor neighborhood, besides it offers relief in hard environmental conditions, giving
rise to the outside temperature as the air conditioner consumes energy and exhausts heat.
In the conclusion of the present research, the LST variations are examined and it
is indicated that there is a momentous variation in the land use in terms of temperature
comparisons. In built-up areas, higher temperature is recorded, followed closely by the
vacant land, while the temperature is less in the areas with water bodies and vegetation. It
is because of the albedo along with the thermal capacity of different land use. It has also
been demonstrated that thermal data received from satellite can be materialized to
measure the spatial extent and magnitude of the urban heat island. An investigation of the
environment can be made by utilizing satellite remote sensing techniques efficiently and
effectively.
178
CHAPTER 6: SUMMARY, CONCLUSION AND
RECOMMENDATIONS
6.1. Summary
The present study used remote sensing techniques to evaluate urban expansion in
terms of the amount of expansion, the location of expansion and the rate of expansion that
has taken place in Lahore during the period from 1951 to 2015. The integration of GIS
and remote sensing techniques has brought about an effective and efficient approach to
identify urban expansion and to assess the impact of urban expansion on land surface
temperature. The study has shown that Lahore has experienced widespread changes in its
land use during the period from 1972 to 2015 at an annual rate of change of 4.46% in its
built area. From the present research it is deduced that, from 1951 to 2015, Lahore has
undergone a massive urban expansion associated with land use changes and this
phenomenon subsequently has resulted in the loss of non-urban lands such as agricultural
land and vegetation cover leading to modification of the thermal characteristics of the
urban land surface in Lahore. In the present study, image classification techniques of
remote sensing provided a comprehensive understanding of the nature, extent, rate, trends
and location of urban expansion and consequential thermal modification. This rapid urban
expansion of Lahore is the outcome of the accelerating economic and industrial activities
along with increase in its urban population as a result of rural to urban migration since
1951.
In the present era, the prevalent circumstances leading to change in land use
patterns and land surface temperature of Lahore, Pakistan are not strange phenomenon in
the urban world, as metropolitan and urban centers of the world have observed the threats
of visible change in urban land use and increase in land surface temperature. The impact
of urban expansion on urban micro-climate has been observed throughout the world and
the metropolitan cities of developing countries like Beijing (Liu et al., 2007), Delhi
(Mohan, 2013), Lahore (Sajjad et al., 2009 and 2015) and Shanghai (Chen et al., 2016),
are not safe and are subject to the environmental change due to the rapid urbanization.
Besides the economic, social and psychological effects of massive urbanization on the
natural environment, the process of urban expansion and its impact on temperature can be
measured quantitatively.
179
According to the present study, since 1951 Lahore, has experienced remarkable
population growth, expansion and developmental activities and they have serious impact
on the urban climate of Lahore. The total urban built-up area of Lahore was 66 km2 in
1951 as shown in Figure 4.12a. The population of Lahore, as reported in 1951, was 1.135
million which increased to 1.626 million in 1961 and its average annual growth rate was
3.66% (GoP, 1961). The inter censual increase of population of Lahore during the decade
from 1951 to 1961 was 0.491 million. During the decade 1951-1961, the increase of
population of Lahore was noted to be 43.3% (Table 4.3).
During the next period of 1961-1972, total urban built-up area was increased to be
170 km2 as shown in Figure 4.12b. Since 1961, the population growth of Lahore began to
increase at a high rate. In the period between 1961 to 1972, Lahore grew at an
unprecedented average annual growth rate of 4.06% (Table 4.3) and during this period the
population of Lahore increased from 1.63 million in 1961 to 2.59 million in 1972 (GoP,
1972). The inter censual increase of population of Lahore during 1961-1972 was 59.2%
(Table 4.3).
The change in urban land use profile of Lahore continued from 1973 to 1980. In
1973, the urban/built-up land of Lahore was 223.96 Km2 which increased to 273.29 Km2
in 1980. It is also noted that the agricultural land decreased from 1213.23 Km2 in 1973 to
1170.57Km2 in 1980 as shown in Table 4.14 and Figures 4.13 and 4.14. During the period
from 1973 to 1980, the urban built-up area increased about 49.33 Km2 (22%) while
agricultural land reduced 42.66 Km2 (4%) as presented in Table 4.15. The population of
Lahore increased rapidly, up to 3.54 million in 1981 which was about 2.59 million in
1972 with annual population growth rate of 3.8% (GOP, 1984). About 1 million people
were added to the total population of Lahore in just one decade, 1972-1981.
During the period 1980-1990, the urban built up area of Lahore increased from
273.29 km2 in 1980 to 352.75 km2 in 1990 as shown in Table 4.14. During this phase, the
changed in urban built-up area of Lahore is 79.46 Km2 while agricultural land constantly
transformed and decreased 52.75 Km2 as presented in Table 4.15, while the population of
Lahore increasing rapidly, was 3.54 million in 1981 with the estimated population in
1990 was 4.95 million. An increase of 1.41 million people was reported to be added in
population of Lahore between 1980 and 1990. During 1980-1990, urban area expanded
180
and included many rural settlements. The city saw rapid expansion eastward and in
southeast direction.
From 1990 to 2000, the urban built-up area of Lahore increased from 352.75 km2
in 1990 to 445.12 km2 in 2000 as shown in Table 4.14. The net accumulation of more
than 92.37 km2 (Table 4.15) of urban built-up land during the period 1990 to 2000 has
converted from agricultural and vacant land use to urban built-up area. The land used for
agriculture reduced from 1117.82 km2 in 1990 to 1062.25 km2 in 2000 (Table 4.14). The
population of Lahore was 4.95 million in the year 1990 and increased to 6.319 million in
1998. An increase of 1.369 million (GoP, 2000) people was reported in the population of
Lahore during the period 1990 to 2000. The average annual growth rate was 3.5%, during
the period from 1981 to 1998 whereas inter-censual increase of population of Lahore was
78.3%. From 1981 to 1998, an increase of 2.74 million of people was recorded in the
population of Lahore.
During the years 2000 to 2010, the built-up area of Lahore enlarged from 445.12
km2 in 2000 to 517.43 km2 in 2010 as shown in Table 4.14 and Figures 4.16 and 4.17.
From 2000 to 2010, the urban built-up land increased to 72.31 km2 (16%) while
agricultural area reduced to 57.26 km2 (5%) and vacant land 11.54 km2 (5%) decreased
from the land use profile of Lahore. During the years 2010 to 2015, the total urban land
recorded was 643.51 km2. The results indicate that in 2010 the total built-up area in
Lahore was 517.43 km2 as shown in Table 4.14 and Figures 4.17 and 4.18. It increased to
643.51 km2 in 2015, thus recording a growth of 57.05 km2 (24%) in urban built-up land.
During this time period, 2010 to 2015, agricultural land was continuously changed and
reduced 34.35(15%) as presented in Table 4.15. The Spatio-temporal analysis revealed
that 419.55 km2 (Table 4.15) of the urban built-up area increased from 1972 to 2015. The
population of Lahore was 2.59 million in 1972, while the population of Lahore was
recorded 9.55 million in 2015 (Estimated). With the growth of population, housing
demand and city development increased and cultivated land was converted into land for
housing colonies, industrial zones and roads. The new housing schemes were approved by
LDA at the cost of fertile agricultural land, to accommodate the demands of the
increasing population of 6.97 million people during the period 1972 to 2015. The targeted
areas under the expansion are south and south east and west along the major roads. As a
181
consequence, the land surface temperature of urban land surface has increased in
comparison with countryside.
The prospect of land use modification as well as climax of the parameters of urban
expansion is a factor of increase in temperature in Lahore. Three different data time series
of MMxT, MMiT and MAT are used to encounter the arguments on the trends and
temporal changes in atmospheric temperature from 1950 to 2015. The outcomes
emphasize that there is no significant change in minimum and maximum air temperature
of Lahore at the airport station (Appendix 01). Figure 5.15 shows that minimum air
temperature rose more than maximum air temperature at urban station. There is not any
significant increase in the maximum atmospheric temperature at both stations, so the
mean temperature of Lahore is not significantly affected by the mean maximum
temperature. It is evident from the analysis that the increase in minimum temperature is
recorded in the urban station related to the rural station situated at the airport which is an
open area. The maximum temperatures recorded at both of the stations have not
experienced any significant change in the time span of 65 years. After 1995, the minimum
temperature started increasing rapidly as Lahore had been undergoing massive urban
development since 1981. It is observed that the increase in minimum temperature at urban
station is due to the population of the city which increased momentously during the study
period. It has been reflected by the results that the change in temperature, over the span of
sixty five years of the study period, is higher for MMiT as compared to MMxT of Lahore.
The Spatio-temporal distribution of emissivity corrected land surface temperature,
has been computed for the period from 1990 to 2015 of Lahore by thermal images. The
statistical data of estimated land surface temperature of the year 1990 shows that the
minimum LST was 16.51°C while the maximum LST was 30.75°C. The mean land
surface temperature was 23.63°C in 1990 as shown in Figure 5.17 and Table 5.9. The
minimum LST in 2000 was 16.99°C while maximum LST was 30.99°C. The mean land
surface temperature was 23.99°C in 2000 as shown in Table 5.9 and Figure 5.18. The
increase in mean land surface temperature of the study period, from 1990 to 2000, is
noted to be 0.36°C as presented in Table 5.10. The land surface temperature ranged from
17.21°C to 31.57°C as shown in Figure 5.19, with a mean land surface temperature of
24.38°C in 2010 as shown in Table 5.10. The increase in mean temperature of the study
period, from 2000 to 2010, is noted to be 0.39°C (Table 5.10). The readings of the LST
182
for the year 2015 show that the highest maximum surface temperature is 33.83°C and the
minimum land surface temperature is 17.40°C as shown in Figure 5.20. The mean land
surface temperature for the year 2015 was 25.62°C. The increased mean land surface
temperature of the study period, from 2010 to 2015, was noted to be 1.23°C as shown in
Table 5.10. The increased mean land surface temperature of Lahore, from 1990 to 2015,
is noted to be 1.98°C as illustrated in Table 5.10. After making the land surface
temperature variation maps (Figures 5.17 to 5.20), it is indicated that the highest land
surface temperature values existed mostly in the center of the city, also known as walled
city, featured by densely built-up area, commercial centers and deep street canyons. The
relatively higher land surface temperatures are observed in industrial zones, urban centers
and highly densely built up areas.
The map in Figure 5.21a represents Town wise LST in March 1990. Town wise
comparison of land surface temperature of Lahore for the year 1990, reflects that the
areas of high temperature are Shalamar Town (24.77°C), Gulbarg Town (24.42°C), Data
Ganj Baksh Town (24.38°C), Ravi Town (24.35°C), Nishtar Town (23.76OC) and Iqbal
Town (23.63OC) as shown in Figure 5.21a. On the other hand, town wise LST map of
March 1990 as shown in Figure 5.21a exhibits that low land surface temperature areas are
Samanabad Town (23.35°C), Wagha Town (23.53°C), Aziz Bhatti Town (22.71°C) and
Cantonment (22.92°C) of Lahore. For comparison, LST is also measured for March 2015
as presented in Figure 5.21b. It is observed in Figure 5.21b that Shalamar Town
(25.57°C), Gulbarg Town (27.85°C), Data Ganj Baksh Town (25.17°C), Ravi Town
(25.78°C), Nishtar Town(25.69°C), Iqbal Town (25.62°C), and Samanabad Town
(25.31°C) have been warmer in March 2015 than March 1990. According to the
assessment, 1.98°C (Table 5.10) land surface temperature of Lahore has increased in last
25 years from 1990 to 2015.
In the conclusion of the present research, the LST variations have been examined
and it has been noted that there is a relationship between modification in the land use and
temperature as displayed in Figure 5.6, 5.7 and 5.23. In built-up land, the highest
temperature is recorded, followed by the vacant land, while the temperature is lower in
the areas with water bodies and vegetation as shown in Figure 5.23. The analysis of
relationship between the remote sensing indices and LST shows that NDVI values
indicate negative correlation between LST, while NDBI values indicate positive
183
correlation between LST with the thermal values. In most of the densely populated and
industrial areas of Lahore, high temperature is being experienced. The process of
intensification of land surface temperature of Lahore is gradual. One of the major issues
in intensification is the reduction in agricultural land in the vicinity of the city area. It is
significant to note that the cultivated land and green spaces had been transformed into
built-up areas and eventually in impervious surfaces, resulting in an increase in
temperature of Lahore.
184
6.2. Conclusion
The land surface temperatures in urban areas are increasing gradually as a
consequence of massive land use changes taking place due to urban expansion. It has led
to reduction in agricultural land and loss of vegetation in cities around the world. Cities
are multifunctional centers of industrial and anthropogenic activities. These functions are
causing urban growth and indicate the impact of urbanization on local climate. Since
1800, studies concerning the recognition of rising temperature phenomenon in urban
areas have increased manifold. A number of scholars (Howard, 1818; Harwood, 2008,
Gabler et al., 2009, James et al., 2014) documented that temperatures in urban areas,
varied from those of the nearby countryside, in line with the greenhouse effects produced
by use of carbon fuelled machinery. UHI is a quantifiable pocket of warm air produced by
a large urban area. This comes as to no surprise as cities signify areas with higher density
of population and centre of concentration of human activities. The cities, in this regard,
consume 60 to 80% of energy produced globally and are contributing to CO2 emission
with equal share (OECD, 2010). A number of studies indicate that the land surface
temperatures of cities are generally (1-6°C) warmer than those of the adjacent rural areas
(Gabler et al., 2009). Several contributing factors include energy use, automobile,
industry, heat generating human activities, thermodynamic capacities of material,
structural geometry and impervious surfaces are responsible for storage of heat and re-
radiation of heat in the atmosphere. These factors in turn change the conditions that alter
the near-surface atmospheric temperature over the urban areas.
The findings of the present study reveal that the city of Lahore over the last few
decades has experienced a rapid population and urban growth. The expansion of urban
areas in Lahore city has influenced the local climate. The urban climate of Lahore is
affected not only by factors of global climactic change in the South Asian region but
indigenous factors of this change have also exercised an adverse impact. The emission of
CO2 in particular, and greenhouse gases in general, contribute towards urban warming in
Lahore. The significant variations in temperature trends of Lahore show increase in
temperature during various years. Moreover, land surface temperature is also
progressively rising in Lahore. One of the leading causes is reduction in the agricultural
area in the city. This notable change creating the climatic condition is known as ‘Urban
Heat Island’ in Lahore. Lahore is undergoing rapid expansion of urban areas and it has
185
caused development of urban heat island. The UHI phenomenon requires the
comprehension of distribution of LST and spatial variations in order to investigate its
mechanism and locate possible solution. Urban heat island effect in Lahore can be
compared with the other major cities of the world as London (Kolokotroni et al., 2006),
Beijing (Liu et al., 2007), Tokyo (Fujibe, 2011), Delhi (Mohan, 2013), Lahore (Sajjad et
al., 2009 and 2015) and Shanghai (Chen et al., 2016) and the contrast calls for
modification in action plans to mitigate UHI effects.
The findings of the study elaborate that the night time temperature increase in
Lahore has also been the main source of change in climatic conditions on local scale. The
construction material is mostly concrete, asphalt and metal. Impervious surfaces absorb
radiation during the daytime and contribute to increase in temperature at night when the
heat absorbed during the day is emitted. The heat radiation in the atmosphere stays and
eventually cause an increase in the value of minimum temperature as speed of the wind in
the city is less than those of the surroundings. The results of the present study showed a
positive relationship between the urban density, air pollutants and increased temperatures.
For the purpose of analysis between air pollutant and air temperature, air quality samples
were collected from different locations in the city of Lahore, which show high population
density areas have high temperature (Appendix 3).
According to the findings of the present research, it is observed that the massive
increase in urban growth resulted in an increased emission of GHGs, particularly CO2,
Carbon monoxide and Sulfur dioxide, forming smog over the city in the shape of
suspended-particle laden layer of thick cloud. Lahore is the fourth worst city for smog
among the ten worst cities of the world for smog (Vergin, 2014). One of the factors
contributing to smog in cities is alternate energy resource in the industries; coal, wood
and other pollution producing fuels. Moreover, the traffic jams in the city also enhance
the emission of Carbon monoxide in the city, creating a thick film of smog. The cloud of
smog traps the emitted and reflected radiation from the surface of the Earth and produces
greenhouse effect. This effect is a major cause of increase in the minimum temperature of
the city. It also affects the mean annual temperature of Lahore. Geographically, the city of
Lahore comes in temperate zone (Low Latitude), located at 31°34' N latitude, where
temperature is comparatively higher, and wind cannot cross through the city easily.
186
During winter, the city remains under the spell of low visibility as perpetual twilight
sustains over the city, the pollutants get stuck in the air and rains are generally rare.
The findings of this research lead us to conclude that the population growth of
Lahore was recorded and estimated from 1.13 million in 1951 to 9.55 million in 2015
(GoP, 2015). The population density of Lahore has also increased from 641 to 5,386
persons/km2 from 1951 to 2015. Especially the period of 1981-1998, the population of
Lahore increased from 3.5 million to 6.3 million respectively, adding three million more
people in the population of Lahore. The average annual population growth rate in the year
1981 was 3.5%. The next period, 1998-2015, experienced a further increase of 6.3 to 9.5
million with population growth rate 3.3 in the year 1998. Almost 3.2 million more people
were added to the population of Lahore. Both the periods of population analysis
confirmed the rapid urban population growth of Lahore. The massive urban population of
Lahore has practically more impact on its urban micro-climate.
The results revealed a substantial increase in the built-up area and impervious
structure for the period 1951 to 2015. The increase recorded in built up area of Lahore is
momentous as it shot from 66 km2 in 1951 to 643.51 km2 in 2015 and has caused an
increased land surface temperature and the urban heat island to experience as well. The
Spatio-temporal analysis reflects that 419.55km2 of the urban built up area has been
increased while 297.52 km2of agricultural lands has been reduced from 1973 to 2015. The
agricultural land of Lahore is noted to be reduced from 1213.23 km2 in 1973 to 915.71
km2 in 2015. The rate of change measured for the urban expansion of Lahore is 9.98% per
year with expansion intensity of 0.56% for the period from 1973 to 2015. The increase
can also be evaluated by the fact that the built-up area was 66 km2 in 1951, while it grew
to 643.51 km2 in 2015. The temporal analysis reflects that 577.51 km2 of the urban built-
up area has increased from the year 1951 to 2015. It has also been noticed that remote
sensing and GIS techniques are efficient for analyzing increased surface temperature with
regard to reduction in vegetation cover and increased urban development.
The results indicate that the land use changes and urban development increased
the mean land surface temperature of Lahore by 1.98°C during the study period from
1990 to 2015. The mean LST was 23.63°C in the year 1990 while it was 25.62°C in 2015.
The Spatio-temporal comparative analysis of temperature shows that the maximum land
surface temperature is 30.75°C while the minimum land surface temperature is 16.51°C
187
as recorded in 1990 as compared to the temperature of 2015, which shows increase when
maximum land surface temperature is 33.83°C while the minimum is 17.40°C. Hence, the
huge alteration in urban land use with the reduction in the urban green spaces, has led to
an increased surface temperature and intensity of urban heat island in Lahore.
The mean atmospheric temperature increased by 1.69°C between the period from
1950 to 2015. The mean atmospheric temperature is 23.43°C in 1950 while mean
atmospheric temperature is 25.11°C in 2015 at urban MET station. It has been noted that
the minimum temperature increased which affected the mean annual temperature of
Lahore at the urban MET station as compared to the rural station. It has also been
observed that the minimum temperature after the year 1995, started increasing at a faster
rate as Lahore experienced rapid urban development and increased urbanization in this
period. The minimum temperature is subject to increase in mean annual temperature
(MAT) of Lahore, especially after 1990s. It is noteworthy that the minimum and
maximum temperature differences in urban and rural stations have shown in Figure 5.35
and accelerating trends since 1995, due to the impact of urban expansion on temperatures.
As the green spaces are converted into the impervious surfaces, the minimum temperature
is affected more than the maximum temperature by the conversion of natural land into
urban structure. This study also observed the impact of urban sprawl on minimum
temperature which is lot more extensive than on maximum temperature.
Lahore is the second largest city of Pakistan in terms of population size and is also
identified as being more vulnerable to increased land surface temperature. However, this
change in the temperature trends and land use of Lahore is not something unique as many
global cities of the developed world are threatened by the precarious change in LST.
Therefore, the effects of urban expansion on local climate are observed to be changing all
over the world. Similarly, cities in the developing world like Lahore are also in danger in
terms of its environmental changes due to urban expansion. For instance, increase in
mean annual temperature of Seoul, South Korea by 1.5°C (Chung et al., 2004), increase
in mean annual temperature of Sao Paolo Brazil by 2°C (Freitas et al., 2007), the
temperature increase of Dhaka (Alam and Rabbani, 2007), tendency of increase in
temperature of Beijing (Liu et al., 2007), increased temperature from 0.28 to 0.44°C in
the Yangtze River delta (Du et al., 2007), raised temperature of Jimeta-Yola, Nigeria by
9°C, (Zemb et al. 2010), increased temperature in Tokyo by 3°C, where the warming rate
188
is higher at night time (Fujibe, 2011), Delhi maximum urban heat island reached 10.7°C
from 8.3°C (Mohan, 2013), raised LST in Bangkok due to impervious surfaces (Hokao et
al., 2012), increased urban heat island effect in Istanbul due to the increased artificial
surfaces (Balçik, 2014) and severe increase in surface urban heat island in Shanghai. It
has been identified that the conversion of agricultural lands into built-up areas is the
major source of increase in temperature in Shanghai (Chen et al., 2016). All the
aforementioned studies conducted in major cities of the world have confirmed the adverse
effect of urban expansion and urbanization on the local climate change. Lahore, one of
the big cities of the developing countries, is facing an environmental threat in terms of air
and surface temperature increase and change in land use due to urban expansion and
anthropogenic activities. The findings of the present study conclude that land use change
and anthropogenic activities have significant impact on the local climate of Lahore, and
this study can offer scientific reasoning for the future planning of the land to be used,
which is directly proportional to the climatic change.
In the present research, satellite remote sensing provides data for the assessment
of land surface temperature variation as this technique offers the opportunity to collect
data of larger areas simultaneously. It is not feasible to collect data over hundred square
kilometers for the assessment of land surface temperature by using instruments and
survey method as it would yield point data to be interpolated to have an access to wide
area coverage. Through remote sensing, it becomes easy to access data of a wide-area
coverage and reduces the problems of approachability. Satellite Remote Sensing
expedites the process of mapping land surface temperature variations and land use change
and intensity of urban heat island at the local and regional scale, as this technique is both
cost effective and accurate in assessment.
Finally, the integration of remote sensing and GIS techniques has demonstrated
that it is an effective and efficient methodology for analyzing and monitoring patterns of
urban expansion and its impact on land surface temperature. Moreover, the present
research shows that the integration of proportionate urban built-up area and greenery
spaces can provide a significant measure to reduce urban heat island effect. The
conclusions drawn from the study signify that the development and the maintenance of
green spaces is critical in sustainable urban planning. These measures reduce the urban
warming and associated effects of the climatic change.
189
6.3. Recommendations
The present study aims at utilizing both readings of temperature from satellite
based LST and meteorological measurements to assess the impact of urban expansion on
land surface temperature of Lahore using remote sensing techniques. Further studies
related to the phenomenon of urban expansion and heat island can be carried out in the
future by keeping in view the recent high resolution satellite (SPOT) images to measure
the current trends, rate and directions of the urban expansion and to monitor the current
land use patterns of Lahore. Eventually, the impact of urban expansion can be analyzed
and assessed by utilizing the current thermal high resolution images in order to measure
the land surface temperature as well as to determine the trends and magnitude of urban
heat island. Furthermore, the population growth, number of vehicles and industrialization
can be monitored in terms of emission of gases which are a potential source of
temperature increase.
Higher resolution satellite imagery is recommended to investigate the
quantification and the classification of land use type for the detailed analysis of different
land use classes. The pixel based analysis and distinguished resolution of the imagery
provide precise and accurate results. It is recommended that for the retrieval of
temperature, ASTER & MODIS data should be utilized for the improvement in the
estimation of LST. The distribution of the each land use type and pattern can be further
investigated in terms of its impact on LST in the urbanized area. The study of the
seasonal changes of temperature correlating with different land uses is recommended. The
future researchers in the field should also try to provide information relating to the surface
temperature that exercises impact on the soil moisture.
Future researches established on the correlation between LST and NDVI are
pertinent for the estimation of temperature in less-vegetated or non-vegetated surfaces,
including water bodies, vacant lands, and man-made features, dead or stressed vegetation.
The influence of the each parameter will have significant potential for classification of
urban thermal environment with more advanced thermal infrared images. It is
recommended that further research may present the Vegetation Sensitivity Index (VSI) a
matric for assessing the sensitivity of a particular environment especially its vegetation
with respect to climatic change. VSI, is a new indicator of vegetation sensitivity to
190
climate changeability and sensitivity index of vegetation productivity to a changing
climate based on water availability, temperature and cloudiness.
Further studies in the future are required to be more focused on the improvement
in retrieval techniques of land surface temperature to reduce the effects of inhomogeneous
atmospheric condition and thin cloud. Various atmospheric effects including variable
surface emissivity, partial water vapour absorption, sub pixel variation of land surface
temperature and urban structure and geometry affect the estimation of LST. It is,
therefore, suggested that these factors may be given consideration while computing the
accurate temperature in future studies. The evaluation of the future land use scenarios is
also recommended to make balanced strategies in spatial morphological arrangements of
different land use. It will also offer alternative to moderate the hot land use types by cold
ones.
It is pertinent to explore the patterns of anthropogenic activities and their impact
and dynamics that may reduce the urban heat island effects, ultimately decreasing global
warming. The errors in every land use type are needed to be removed by estimating
temperature accurately. The patterns of the study can also be extended for the estimation
of GHGs from the satellite data and to relate it with the observations of ground
observatories of CO2 and to comprehend the real-time variation of CO2 intensity on earth
surface.
Change in LST of Lahore in not only the result of alteration in urban land use of
Lahore but also the repercussion of multifarious changes which have been taking place in
cities/places near Lahore particularly in neighboring states of Punjab and Haryana (India)
where every year in the months of October/ November paddy fields are burnt to prepare
fields for winter crops like wheat. This factor is interesting and can further be investigated
in future research in this area of prime importance. The growing number of thermal
power plants to produce electricity in the province may also be responsible for increasing
temperatures of Lahore. In conclusion, these parameters are recommended to be
studied/analyzed in future research in this field.
The method of applying the remote sensing techniques as used in this research can
be applied as a substitute for traditional empirical observations in finding the in-situ data
for analysis of environmental and climatic change studies. It is recommended that the
191
similar methodology be utilized for the analysis of the regions other than Lahore in
Pakistan that experience massive urbanization. The researches in the future will also
provide the recommendations focused on managing thermal environment in accordance
with the land use management of the big cities. The future research should invite
investigation into the reduction of UHI effects with measures reducing heat in cities.
In analogous studies like this one, many statistical methods, e.g. regression and
time series, are applied to remotely sense data to infer results and future researchers
should be aware of the growing potential of the application of spatial statistics. It is
suggested that the researchers who undertake work in this field to examine the
relationships between land use type and surface temperature at a particular point in time
should apply spatial statistics for accurate and reliable results. Spatial statistics is directly
related to two fundamental properties of remotely sensed data, spatial autocorrelation and
spatial heterogeneity. This is particularly true when remote sensing applications
concerned with spatial variability, the relationships between different attributes and
statistical methods draw a particular result based on geostatsitical theory.
192
REFERENCES
Ackerman, B. 1985. Temporal march of the Chicago heat island. Journal of climate and
applied meteorology, 24, 547-554.
Adinna, E., Christian, E. I. and Okolie, A. T. 2009. Assessment of urban heat island and
possible adaptations in Enugu urban using landsat-ETM. Journal of Geography and
Regional Planning, 2(2), 30.-36
Adu-Poko, I., Drummond, J. & Li, Z. 2012. Land-cover change monitoring in Obuasi,
Ghana: an integration of earth observation, geoinformation systems and stochastic
modelling. Journal of Earth Science and Engineering, 2, 1-14.
Afsar, S., Kazmi, J. H. and Bano, S. 2013. Examining the Impacts of Land Use Changes
in Land Surface Temperature (LST) in Karachi through the time Series of Landsat Data.
Journal of Basic and Applied Sciences, 10(1), 222-230.
Agam, N., Kustas, W. P., Anderson, M. C., Li, F. & ColaizzI, P. D. 2008. Utility of
thermal image sharpening for monitoring field‐scale evapotranspiration over rain fed and
irrigated agricultural regions. Geophysical Research Letters, 35.
Agarwal, C., Green, G. M., Grove, J. M., Evans, T. P. & Schweik, C. M. 2002. A review
and assessment of land-use change models: dynamics of space, time, and human choice.
Aguilera, F., Valenzuela, L. M. & Botequilha-Leitão, A. 2011. Landscape metrics in the
analysis of urban land use patterns: A case study in a Spanish metropolitan area.
Landscape and Urban Planning, 99, 226-238.
Ahmed, B., Kamruzzaman, M., Zhu, X., Rahman, M. S. & Choi, K. 2013. Simulating
land cover changes and their impacts on land surface temperature in Dhaka, Bangladesh.
Remote Sensing, 5, 5969-5998.
Akbari, H., Davis, S., Huang, J., Dorsano, S., & Winnett, S. 1992. Cooling our
communities: a guidebook on tree planting and light-colored surfacing: Lawrence
Berkeley Lab., CA (United States); Environmental Protection Agency, Washington, DC
(United States). Climate Change Division.
http://www.osti.gov/energycitations/servlets/purl/5032229-bDvBcf/5032229.pdf
[Accessed 22 August 2013].
193
Akbari, H., Gartland, L. and Konopacki, S. 1998. Measured energy savings of light
colored roofs: Results from three California demonstration sites. Lawrence Berkeley
National Lab., Environmental Energy Technologies Div., Berkeley, CA (United States).
Akbari, H., Pomerantz, M. and Taha, H. 2001. Cool surfaces and shade trees to reduce
energy use and improve air quality in urban areas. Solar energy, 70, 295-310.
Akinbode, O., Eludoyin, A., & Fashae, O. 2008. Temperature and relative humidity
distributions in a medium-size administrative town in southwest Nigeria. Journal of
environmental management, 87(1), 95-105.
Alcoforado, M. J. & Andrade, H. 2008. Global warming and the urban heat island. Urban
ecology. Springer.
Alam, M. & Rabbani, M. G. 2007. Vulnerabilities and responses to climate change for
Dhaka. Environment and urbanization, 19, 81-97.
Almas, A. S., Rahim, C., Butt, M., & Shah, T. I. 2005. Metropolitan growth monitoring
and land use classification using geospatial techniques. Paper presented at the
Proceedings of International Workshop on Service and Application of Spatial Data
Infrastructure, Hangzhou, China. http://henu.geodata.cn/Portal/wenxian/papers/277-
282%20Amjed%20S.%20Almas-A039.pdf [Accessed on 22 August 2013].
Alphan, H. 2003. Land‐use change and urbanization of Adana, Turkey. Land degradation
& development, 14, 575-586.
Alrababah, M. & Alhamad, M. 2006. Land use/cover classification of arid and semi‐arid
Mediterranean landscapes using Landsat ETM. International journal of remote sensing,
27, 2703-2718.
Anderson, J. R. 1976. A land use and land cover classification system for use with remote
sensor data, US Government Printing Office.
Anderson, M., Kustas, W., Norman, J., Hain, C., Mecikalski, J., Schultz, L., González-
Dugo, M., Cammalleri, C., D'urso, G. & Pimstein, A. 2011. Mapping daily
evapotranspiration at field to continental scales using geostationary and polar orbiting
satellite imagery. Hydrology and Earth System Sciences, 15, 223-239.
194
Angel, S., Sheppard, S., Civco, D. L., Buckley, R., Chabaeva, A., Gitlin, L., Kraley, A.,
Parent, J. & Perlin, M. 2005. The dynamics of global urban expansion, World Bank,
Transport and Urban Development Department Washington, DC.
Ao, K. F., & Ngo, H. T. M. 2000. GIS analysis of Vancouver’s urban heat island.
Available at: http://www.geog.ubc.ca/courses/klink/g470/class00/kfao/abstract.html.
[Accessed 23 August].
Aniello, C., Morgan, K., Busbey, A. & Newland, L. 1995. Mapping micro-urban heat
islands using Landsat TM and a GIS. Computers & Geosciences, 21, 965-969.
Anwar M. M., and Bhalli, M.N. 2012. Urban population growth monitoring and land use
classification by using GIS and Remote Sensing techniques: a case study of Faisalabad
city. Asian journal of social sciences & humanities, 1(1), 05-13.
Arif, G. M. and Hamid (2007) Life in the City: Pakistan in Focus. UNFPA, Islamabad,
Pakistan.
Arif, G. M. and Hamid (2007a) Gender Dimensions in Rural-Urban Migration in
Pakistan. Paper presented in 8th Population Association of Pakistan, Conference held in
Islamabad 18-19 November.
Authority, G. L. 2006. London’s urban heat island: a summary for decision makers.
London: Greater London
Authority.http://static.london.gov.uk/mayor/environment/climatechange/docs/UHIsumma
ryreport.pdf [Accessed 10 Mar 2013].
Bähr, H.-P. 2001. Image segmentation for change detection in urban environments.
Baig, A. A. and Jillian, R. 2013. Monitoring of Satellite based Spatial and Temporal
Change in Land Surface Temperature of Lahore. 3rd International Conference on
Aerospace Science & Engineering (ICASE2013) August 21-23, 2013 Islamabad,
Pakistan.
Bannari, A., Morin, D., Bonn, F. & Huete, A. 1995. A review of vegetation indices.
Remote sensing reviews, 13, 95-120.
Barnes, K. B., Morgan III, J. M., Roberge, M. C. & Lowe, S. 2001. Sprawl development:
its patterns, consequences, and measurement. Towson University, Towson, 1-24.
195
Barnsley, M. & Barr, S. 1996. Inferring urban land use from satellite sensor images using
kernel-based spatial reclassification. Photogrammetric Engineering and Remote Sensing,
62, 949-958
Barsi, J. A., Schott, J., Palluconi, F. D., Helder, D., Hook, S., Markham, B., Chander, G.
& O'donnelL, E. 2003. Landsat TM and ETM+ thermal band calibration. Canadian
Journal of Remote Sensing, 29, 141-153.
Basar, U., Kaya, S. & Karaca, M. 2008. Evaluation of urban heat island in Istanbul using
remote sensing techniques [Online]. Available:
http://www.isprs.org/proceedings/XXXVII/congress/7_pdf/5_WG-VII-5/40.pdf.
Betts, R. A. 1999. Self‐beneficial effects of vegetation on climate in an ocean‐atmosphere
general circulation model. Geophysical Research Letters, 26, 1457-1460.
Bhandari, S. 2010. Urban change monitoring using GIS and remote sensing tools in
Kathmandu valley (Nepal).
Bhalli, M.N. and Ghaffar, A. 2015. Use of Geospatial Techniques in Monitoring Urban
Expansion and Land Use Change Analysis: A Case of Lahore, Pakistan. Journal of Basic
& Applied Sciences, 11, 265-273.
Bhatta, B. 2008. Remote sensing and GIS, Oxford University Press New Delhi.
Bhatta, B. 2009. Analysis of urban growth pattern using remote sensing and GIS: a case
study of Kolkata, India. International Journal of Remote Sensing, 30, 4733-4746.
Bierkens, M. F., Dolman, A. J. & Troch, P. A. 2008. Climate and the hydrological cycle,
International Association of Hydrological Sciences.
Blankenstein, S. and Kuttler, W. 2004. Impact of street geometry on downward longwave
radiation and air temperature in an urban environment. Meteorologische Zeitschrift, 13,
373-379.
Bounoua, L., Defries, R., Collatz, G. J., Sellers, P. & Khan, H. 2002. Effects of land
cover conversion on surface climate. Climatic Change, 52, 29-64.
Bousse, Y. S. 2009. Mitigating the urban heat island effect with an intensive green roof
during summer in Reading, UK. Master’s Thesis, Reading University, Reading, UK.
196
Bouyer, J., Musy, M., Huang, Y. and Athamena, K. 2009. Mitigating urban heat island
effect by urban design: forms and materials. Proceedings of the 5th urban research
symposium, cities and climate change: responding to an urgent agenda, Marseille, 28-30.
Brandsma, T. & Wolters, D. 2012. Measurement and statistical modeling of the urban
heat island of the city of Utrecht (the Netherlands). Journal of Applied Meteorology and
Climatology, 51, 1046-1060.
Brown, J. F., Wardlow, B. D., Tadesse, T., Hayes, M. J. & Reed, B. C. 2008. The
Vegetation Drought Response Index (VegDRI): A new integrated approach for
monitoring drought stress in vegetation. GIScience & Remote Sensing, 45, 16-46.
Burchell, R. W., Shad, N., Listokin, D., Phillips, H., Downs, A., Seskin, S., Davis, J.,
Moore, T., Helton, D. & Gall, M. 1998. The Costs of Sprawl-Revisited. Transit
Cooperative Research Program (TCRP) Report 39. Transportation Research Board:
Washington, DC, USA.
Camilloni, I., & Barrucand, M. 2012. Temporal variability of the Buenos Aires,
Argentina, urban heat island. Theoretical and Applied Climatology, 107(1-2), 47-58.
Carlson, T. 2007. An overview of the" Triangle Method" for estimating surface
evapotranspiration and soil moisture from satellite imagery. Sensors, 7, 1612-1629.
Carnahan, W. H., & Larson, R. C. 1990. An analysis of an urban heat sink. Remote
sensing of Environment, 33(1), 65-71.
Chander, G. & Markham, B. 2007. Revised Landsat 5 TM radiometric calibration
procedures and post-calibration dynamic ranges. 2003.
Chandler, T. J. 1960. Wind as A Factor of Urban Temperatures—A Survey in North‐East
London. Weather, 15, 204-213.
Chandler, T. J. 1965. The climate of London, Hutchinson.
Chapin, F., Sturm, M., Serreze, M., Mcfadden, J., Key, J., Lloyd, A., Mcguire, A., Rupp,
T., Lynch, A. & Schimel, J. 2005. Role of land-surface changes in Arctic summer
warming. Science, 310, 657-660.
Charabi, Y., & Bakhit, A. 2011. Assessment of the canopy urban heat island of a coastal
arid tropical city: The case of Muscat, Oman. Atmospheric Research, 101(1), 215-227.
197
Chase, T., Pielke SR, R., Kittel, T., Nemani, R. & Running, S. 2000. Simulated impacts
of historical land cover changes on global climate in northern winter. Climate Dynamics,
16, 93-105.
Chen, L., Jiang, R. and Xiang, W. N. 2015. Surface Heat Island in Shanghai and Its
Relationship with Urban Development from 1989 to 2013. Advances in Meteorology,
2016.
Chen, S. S., & Jim, C. 2003. Quantitative assessment of the trees cape and cityscape of
Nanjing, China. Landscape ecology, 18(4), 395-412.
Chen, X. L., Zhao, H. M., Li, P.-X., & Yin, Z. Y. 2006. Remote sensing image-based
analysis of the relationship between urban heat island and land use/cover changes.
Remote sensing of Environment, 104(2), 133-146.
Chen, Y. H., Wang, J. & LI, X.-B. 2002. A study on urban thermal field in summer based
on satellite remote sensing. Remote Sensing for Land and Resources, 4.
Cheng, J. & Masser, I. 2003. Urban growth pattern modeling: a case study of Wuhan city,
PR China. Landscape and urban planning, 62, 199-217.
Chia, L. S. 1970. Temperature and humidity observations on two overcast days in
Singapore. Journal of the Singapore National Academy of Science, 1, 85-90.
Christy, J. R., Norris, W. B., Redmond, K. & Gallo, K. P. 2006. Methodology and results
of calculating central California surface temperature trends: evidence of human-induced
climate change? Journal of Climate, 19, 548-563.
Chung, U., Choi, J. & Yun, J. I. 2004. Urbanization effect on the observed change in
mean monthly temperatures between 1951-1980 and 1971-2000 in Korea. Climatic
Change, 66, 127-136.
Chuvieco, E. 2008. The Role of Satellite Remote Sensing in Monitoring the Global
Environment. , New York: Springer Science + Business Media.
Clarke, J. and Peterson, J. 1972. Effect of regional climate and land use on nocturnal heat
island. Bulletin of the American meteorological society, Amer meteorological SOC 45
Beacon st, Boston, ma 02108-3693, 714.
198
Cleve, C., Kelly, M., Kearns, F. R. & Moritz, M. 2008. Classification of the wild land–
urban interface: A comparison of pixel-and object-based classifications using high-
resolution aerial photography. Computers, Environment and Urban Systems, 32, 317-326.
Collatz, G. J., Bounoua, L., Los, S., Randall, D., Fung, I. & Sellers, P. 2000. A
mechanism for the influence of vegetation on the response of the diurnal temperature
range to changing climate. Geophysical Research Letters, 27, 3381-3384.
Coltri, P. P., Ferreira, N. J., Freitas, S., & Demetrio, V. A. 2009. Changes in land cover
and use affect the local and regional climate in Piracicaba, Brazil. Journal of Urban and
Environmental Engineering (JUEE), 2(2), 68-74.
Congalton, R. G. & Green, K. 2008. Assessing the accuracy of remotely sensed data:
principles and practices, CRC press.
Coppin, P., Jonckheere, I., Nackaerts, K., Muys, B. & Lambin, E. 2004. Review Article
Digital change detection methods in ecosystem monitoring: a review. International
journal of remote sensing, 25, 1565-1596.
Cox, J. R. 2011. Cool Neighborhoods within the New York Metro Heat Island; city
weathers: meteorology and urban design 1950-2010.
http://www.sed.manchester.ac.uk/architecture/research/csud/workshop/programme/Cox_
NewYork.pdf.[ Accessed 14 Aug 2013].
Defries, R. S., Rudel, T., Uriarte, M. & Hansen, M. 2010. Deforestation driven by urban
population growth and agricultural trade in the twenty-first century. Nature Geoscience,
3, 178-181.
Deosthali, V. 2000. Impact of rapid urban growth on heat and moisture islands in Pune
City, India. Atmospheric Environment, 34, 2745-2754.
Dewan, A. M. & Yamaguchi, Y. 2009. Using remote sensing and GIS to detect and
monitor land use and land cover change in Dhaka Metropolitan of Bangladesh during
1960–2005. Environmental monitoring and assessment, 150, 237-249.
Dong, Y., Forster, B. & Ticehurst, C. 1997. Radar backscatter analysis for urban
environments. International Journal of Remote Sensing, 18, 1351-1364.
Donnay, J.-P., Barnsley, M. J. & Longley, P. A. 2003. Remote Sensing and Urban
Analysis: GISDATA 9, CRC Press.
199
Dousset, B. & Gourmelon, F. 2003. Satellite multi-sensor data analysis of urban surface
temperatures and land cover. ISPRS Journal of Photogrammetry and Remote Sensing, 58,
43-54.
Dozier, J. 1989. Spectral signature of alpine snow cover from the Landsat Thematic
Mapper. Remote sensing of Environment, 28, 9-22.
Du, Y., Xie, Z., Zeng, Y., Shi, Y. & Wu, J. 2007. Impact of urban expansion on regional
temperature change in the Yangtze River Delta. Journal of Geographical Sciences, 17,
387-398.
EPA. 2003. Cooling Summertime Temperatures: Strategies to Reduce Urban Heat
Islands [Online]. United States Environmental Protection Agency. Available:
http://www.epa.gov/heatisland/resources/pdf/HIRIbrochure.pdf [Accessed 23 DEC 2014].
EPA. 2008. Reducing Urban Heat Islands: Compendium of Strategies. . Climate
Protection Partnership Division U.S. Washington, DC: U.S. Environmental Protection
Agency. Available at: http://www.epa.gov/heatisland/resources/compendium.htm
[Accessed 23 August, 2014].
Epsteln, J., Payne, K. & Kramer, E. 2002. Techniques for mapping suburban sprawl.
Photogrammetric engineering & remote sensing, 63, 913-918.
Eum, J.-H., Scherer, D., Fehrenbach, U. & Woo, J.-H. 2011. Development of an urban
land cover classification scheme suitable for representing climatic conditions in a densely
built-up Asian megacity. Landscape and Urban Planning, 103, 362-371.
Ezber, Y., Lutfi Sen, O., Kindap, T. & Karaca, M. 2007. Climatic effects of urbanization
in Istanbul: a statistical and modeling analysis. International Journal of Climatology, 27,
667-679.
Fan, F., Wang, Y., Qiu, M., & Wang, Z. 2009. Evaluating the temporal and spatial urban
expansion patterns of Guangzhou from 1979 to 2003 by remote sensing and GIS methods.
International Journal of Geographical Information Science, 23(11), 1371-1388.
Feddema, J. J., Oleson, K. W., Bonan, G. B., Mearns, L. O., Buja, L. E., Meehl, G. A. &
Washington, W. M. 2005. The importance of land-cover change in simulating future
climates. Science, 310, 1674-1678.
200
Foody, G. M. 2002. Status of land cover classification accuracy assessment. Remote
sensing of environment, 80, 185-201.
Freeman, L. 2001. The effects of sprawl on neighborhood social ties: An explanatory
analysis. Journal of the American Planning Association, 67, 69-77.
Freitas, E. D., Rozoff, C. M., Cotton, W. R. & Dias, P. L. S. 2007. Interactions of an
urban heat island and sea-breeze circulations during winter over the metropolitan area of
São Paulo, Brazil. Boundary-Layer Meteorology, 122, 43-65.
Friedel, M. J. 2012. Data-driven modeling of surface temperature anomaly and solar
activity trends. Environmental Modelling & Software, 37, 217-232.
Fujibe, F. 2010. Day-of-the-week variations of urban temperature and their long-term
trends in Japan. Theoretical and applied climatology, 102, 393-401.
Fujibe, F. 2011. Urban warming in Japanese cities and its relation to climate change
monitoring. International Journal of Climatology, 31, 162-173.
Fung, T. & Ledrew, E. 1987. Application of principal components analysis change
detection. Photogrammetric Engineering and Remote Sensing, 53(12), 1649–1658.
Fung, W., Lam, K., Nichol, J. & Wong, M. S. 2009. Derivation of nighttime urban air
temperatures using a satellite thermal image. Journal of Applied Meteorology and
Climatology, 48, 863-872.
Gallego, F. J. 2004. Remote sensing and land cover area estimation. International Journal
of Remote Sensing, 25, 3019-3047.
Gallo, K. P., & Owen, T. W. 1999. Satellite-based adjustments for the urban heat island
temperature bias. Journal of Applied Meteorology, 38(6), 806-813.
Gao, B. C. 1996. NDWI—a normalized difference water index for remote sensing of
vegetation liquid water from space. Remote sensing of Environment, 58(3), 257-266.
Gao, J. 2008. Mapping of land degradation from ASTER data: a comparison of object-
based and pixel-based methods. GIScience & Remote Sensing, 45, 149-166.
Garcia-Cueto, O. R., Jauregui-Ostos, E., Toudert, D., & Tejeda-Martinez, A. 2007.
Detection of the urban heat island in Mexicali, BC, México and its relationship with land
use. Atmósfera, 20(2), 111-131.
201
Gartland, L. 2010. Heat islands: understanding and mitigating heat in urban areas,
Routledge.
Gatrell, J. D. & Jensen, R. R. 2008. Sociospatial applications of remote sensing in urban
environments. Geography Compass, 2, 728-743.
Ghaffar, A. 2006. Assessing urban sprawl in Lahore by using RS/GIS techniques.
Pakistan Geographical Review, 61(2), 99-102.
Gillies, R., Kustas, W. & Humes, K. 1997. A verification of the' triangle' method for
obtaining surface soil water content and energy fluxes from remote measurements of the
Normalized Difference Vegetation Index (NDVI) and surface e. International Journal of
Remote Sensing, 18, 3145-3166.
Giridharan, R., Ganesan, S. and Lau, S. 2004. Daytime urban heat island effect in high-
rise and high-density residential developments in Hong Kong. Energy and Buildings, 36,
525-534.
Gitelson, A. A. & Merzlyak, M. N. 1996. Signature analysis of leaf reflectance spectra:
algorithm development for remote sensing of chlorophyll. Journal of plant physiology,
148, 494-500.
Goetz, S., Varlyguin, D., Smith, A., Wright, R., Prince, S., Mazzacato, M., Melchoir, B.
2004. Application of multi-temporal Landsat data to map and monitor land cover and land
use change in the Chesapeake Bay watershed. Analysis of Multi-temporal remote sensing
image, World Scientific Publishers, Singapore, 223-232.
Goldblum, C. & Wong, T.-C. 2000. Growth, crisis and spatial change: a study of
haphazard urbanization in Jakarta, Indonesia. Land Use Policy, 17, 29-37.
Gong, P., Wang, J., Yu, L., Zhao, Y., Zhao, Y., Liang, L., Niu, Z., Huang, X., Fu, H. &
Liu, S. 2013. Finer resolution observation and monitoring of global land cover: first
mapping results with Landsat TM and ETM+ data. International Journal of Remote
Sensing, 34, 2607-2654.
GoP. 1961. District Census Report of Lahore 1961. Islamabad: Population Census
Organization, Statistics Division. Govt. of Pakistan.
GoP. 1972. District Census Report of Lahore 1972. Islamabad: Population Census
Organization, Statistics Division. Govt. of Pakistan.
202
GoP. 1984. District Census Report of Lahore 1981. Islamabad: Population Census
Organization, Statistics Division. Govt. of Pakistan.
GoP. 1998. Population size and growth of major cities. Pakistan Bureau of Statistical,
Government of Pakistan. Available
at:http://www.pbs.gov.pk/sites/default/files/tables/population%20size%20and%20growth
%20of%20major%20cities.pdf [Accessed 23 August 2013].
GoP. 2000. District Census Report of Lahore 1998. Islamabad: Population Census
Organization, Statistics Division. Govt. of Pakistan.
GoP. 2004. City Report of Lahore 1998. Islamabad: Population Census Organization,
Statistics Division, Govt. of Pakistan.
GoP. (2005) Basic population and housing data by union councils 1998. Islamabad:
Population Census Organization, Statistics Division.
GoP. (2005) Punjab development statistics. Lahore: Bureau of Statistics Lahore, Pakistan.
GoP, (2009) Pakistan statistical year book 2009. Islamabad: Federal Bureau of Statistic,
Pakistan
GoP. (2010) Pakistan economic survey 2009-2010. Islamabad: Finance Division
Islamabad, Pakistan.
GoP. (2011) Pakistan economic survey 2010-2011. Islamabad: Finance Division
Islamabad, Pakistan.
GoP. (2014) Pakistan economic survey 2013-2014. Islamabad: Finance Division
Islamabad, Pakistan.
GoP. (2015) Pakistan economic survey 2014-2015. Islamabad: Finance Division
Islamabad, Pakistan.
GoP. 2012. Punjab development statistics 2012. Bureau of Statistics Lahore. Government
of the Punjab. Pakistan.
GoP. 2013. Punjab development statistics 2013. Bureau of Statistics Lahore. Government
of the Punjab. Pakistan.
GoP. 2014. Punjab development statistics 2014. Bureau of Statistics Lahore. Government
of the Punjab. Pakistan.
203
GoP. 2015. Punjab development statistics 2015. Bureau of Statistics Lahore.
Government of the Punjab. Pakistan.
Griffiths, P., Hostert, P., Gruebner, O. & Der Linden, S. V. 2010. Mapping megacity
growth with multi-sensor data. Remote Sensing of Environment, 114, 426-439.
Grimm, N. B., Morgan Grove, J., Pickett, S. T., & Redman, C. L. 2000. Integrated
Approaches to Long-TermStudies of Urban Ecological Systems: Urban ecological
systems present multiple challenges to ecologists-pervasive human impact and extreme
heterogeneity of cities, and the need to integrate social and ecological approaches,
concepts, and theory. BioScience, 50(7), 571-584.
Guillevic, P., Koster, R., Suarez, M., Bounoua, L., Collatz, G., Los, S. & Mahanama, S.
2002. Influence of the interannual variability of vegetation on the surface energy balance-
a global sensitivity study. Journal of Hydrometeorology, 3, 617-629.
Guillevic, P. C., Privette, J. L., Coudert, B., Palecki, M. A., Demarty, J., Ottlé, C. &
Augustine, J. A. 2012. Land Surface Temperature product validation using NOAA's
surface climate observation networks—Scaling methodology for the Visible Infrared
Imager Radiometer Suite (VIIRS). Remote Sensing of Environment, 124, 282-298.
Guindon, B., Zhang, Y. & Dillabaugh, C. 2004. Landsat urban mapping based on a
combined spectral–spatial methodology. Remote Sensing of Environment, 92, 218-232.
Gumma, M. K., Thenkabail, P. S., Hideto, F., Nelson, A., Dheeravath, V., Busia, D. &
Rala, A. 2011. Mapping irrigated areas of Ghana using fusion of 30 m and 250 m
resolution remote-sensing data. Remote Sensing, 3, 816-835.
Hall, D. K., Riggs, G. A. & Salomonson, V. V. 1995. Development of methods for
mapping global snow cover using moderate resolution imaging spectroradiometer data.
Remote sensing of Environment, 54, 127-140.
Hamdan, H., Yusof, F. & Marzukhi, M. A. 2014. Social Capital and Quality of Life in
Urban Neighborhoods High Density Housing. Procedia-Social and Behavioral Sciences,
153, 169-179.
Hansen, M., Defries, R., Townshend, J. R. & Sohlberg, R. 2000. Global land cover
classification at 1 km spatial resolution using a classification tree approach. International
Journal of Remote Sensing, 21, 1331-1364.
204
Hardegree, L. C. 2006. Spatial Characteristics of the Remotely-Sensed Surface Urban
Heat Island in Baton Rouge, LA: 1988-2003. University of Alabama.
Haregeweyn, N., Fikadub, G., Tsunekawa, A., & Tsubo, M. 2012. The dynamics of urban
expansion and its impacts on land use/land cover change and small-scale farmers living
near the urban fringe: A case study of Bahir Dar, Ethiopia. Landscape and Urban
Planning, 106, 149-157.
Haregeweyn, N., Fikadu, G., Tsunekawa, A., Tsubo, M. & Meshesha, D. T. 2012. The
dynamics of urban expansion and its impacts on land use/land cover change and small-
scale farmers living near the urban fringe: A case study of Bahir Dar, Ethiopia.
Landscape and urban planning, 106, 149-157.
Harwood IV, J. W. 2008. Delineation and GIS Mapping of Urban Heat Islands Using
Landsat TM Imagery. Kent State University.
Hashim, N. B. M., Asmala, A., & Abdullah, M. 2007. Mapping urban heat island
phenomenon: Remote sensing approach. Journal-The Institution of Engineers, Malaysia,
68(3), 25-30.
Hathout, S. 2002. The use of GIS for monitoring and predicting urban growth in East and
West St Paul, Winnipeg, Manitoba, Canada. Journal of Environmental management, 66,
229-238.
Hawkins, T. W., Brazel, A. J., Stefanov, W. L., Bigler, W. & Saffell, E. M. 2004. The
role of rural variability in urban heat island determination for Phoenix, Arizona. Journal
of Applied Meteorology, 43, 476-486.
He, C., Okada, N., Zhang, Q., Shi, P. & LI, J. 2008. Modelling dynamic urban expansion
processes incorporating a potential model with cellular automata. Landscape and urban
planning, 86, 79-91.
Herold, M., Goldstein, N. C. & Clarke, K. C. 2003. The spatiotemporal form of urban
growth: measurement, analysis and modeling. Remote sensing of Environment, 86, 286-
302.
Herold, M., Roberts, D. A., Gardner, M. E. & Dennison, P. E. 2004. Spectrometry for
urban area remote sensing-Development and analysis of a spectral library from 350 to
2400 nm. Remote Sensing of Environment, 91, 304-319.
205
He, C., Okada, N., Zhang, Q., Shi, P., & Zhang, J. 2006. Modeling urban expansion
scenarios by coupling cellular automata model and system dynamic model in Beijing,
China. Applied Geography, 26(3), 323-345.
He, C., Okada, N., Zhang, Q., Shi, P., & Li, J. (2008). Modelling dynamic urban
expansion processes incorporating a potential model with cellular automata. Landscape
and urban planning, 86(1), 79-91.
Hestir, K. L. 2011. Land cover classification and change detection in dry lands: an
evaluation of remote sensing approaches. New Mexico State University.
Hokao, K. & Phonekeo, V. & Srivanit, M. 2012. Assessing the Impact of Urbanization
on Urban Thermal Environment: A Case Study of Bangkok Metropolitan. International
Journal of Applied, 2, 243-256.
Houghton, J. T. 1996. Climate change 1995: The science of climate change: contribution
of working group I to the second assessment report of the Intergovernmental Panel on
Climate Change, Cambridge University Press.
Houghton, J., Ding, Y., Griggs, D., Noguer, M., Van DER Linden, P., Dai, X., Maskell,
K. & Johnson, C. 2001. IPCC Third Assessment Report: Climate Change, 2001 (TAR).
Working group I: the scientific basis.
Howard, L. 1818. The Climate of London: Deduced from Meteorological Observations,
Made at Different Places in the Neighbourhood of the Metropolis, W. Phillips, sold also
by J. and A. Arch.
Howarth, P. J. & Boasson, E. 1983. Landsat digital enhancements for change detection in
urban environments. Remote Sensing of Environment, 13, 149-160.
Harwood, J.W. 2008. Delineation and GIS Mapping of Urban Heat Islands Using Landsat
TM Imagery. (Unpublished MA thesis). Kent, Ohio: Kent State University.
Huang, G., Zhou, W. & Cadenasso, M. 2011. Is everyone hot in the city? Spatial pattern
of land surface temperatures, land cover and neighborhood socioeconomic characteristics
in Baltimore, MD. Journal of environmental management, 92, 1753-1759.
Huete, A. R. 1988. A soil-adjusted vegetation index (SAVI). Remote sensing of
environment, 25, 295-309.
206
Im, J., Jensen, J. & Tullis, J. 2008. Object‐based change detection using correlation image
analysis and image segmentation. International Journal of Remote Sensing, 29, 399-423.
Ifatimehin, O. O. and Ufuah, M. E. 2006. An Analysis of Urban Expansion and Loss of
Vegetation Cover in Lokoja, Using GIS Techniques. The Zaria Geographers, 17(1), 28-
36.
Imhoff, M. L., Zhang, P., Wolfe, R. E. & Bounoua, L. 2010. Remote sensing of the urban
heat island effect across biomes in the continental USA. Remote Sensing of Environment,
114, 504-513.
Irons, J. R., Dwyer, J. L. & Barsi, J. A. 2012. The next Landsat satellite: The Landsat data
continuity mission. Remote Sensing of Environment, 122, 11-21.
Jackson, R. & Huete, A. 1987. Suitability of Spectral Indices for Evaluating Vegetation
Characteristics on Arid Rangelands.
Jackson, T. J., Chen, D., Cosh, M., Li, F., Anderson, M., Walthall, C., Hunt, E. 2004.
Vegetation water content mapping using Landsat data derived normalized difference
water index for corn and soybeans. Remote sensing of Environment, 92(4), 475-482.
Jan, B. and Iqbal, M. 2008. Urbanization trend and urban population projections of
Pakistan using weighted approach. Sarhad Journal of Agriculture (Pakistan), 24(1), 173-
180.
James, M. M. & Charles, N.M. 2014. Dynamism of Land use Changes on Surface
Temperature in Kenya: A Case Study of Nairobi City. International Journal of Science
and Research (IJSR), 3(4), 38-41.
Jat, M. K., Garg, P. & Khare, D. 2008. Modelling of urban growth using spatial analysis
techniques: a case study of Ajmer city (India). International Journal of Remote Sensing,
29, 543-567.
Jensen, J. 2004. Digital change detection. Introductory digital image processing: A
remote sensing perspective (pp. 467-494). New Jersey: Prentice-Hall. DOI.
Jensen, J., Cowen, D., Althausen, J., Narumalani, S. & Weatherbee, O. 1993. An
evaluation of the Coast Watch change detection protocol in South Carolina.
Photogrammetric Engineering and Remote Sensing, 59, 1039-1044.
207
Jensen, J. R. 2005. Introductory digital image processing: a remote sensing perspective,
3rd ed, Prentice Hall, Upper Saddle River, N.J.
Jensen, J. R. 2006. Remote Sensing of the Environment: An Earth Resource Perspective,
Upper Saddle River, NJ: Prentice Hall.
Jensen, J. R. 2009. Remote Sensing of the Environment: An Earth Resource Perspective
2/e, Pearson Education India.
Jensen, J. R. & Cowen, D. C. 1999. Remote sensing of urban/suburban infrastructure and
socio-economic attributes. Photogrammetric engineering and remote sensing, 65, 611-
622.
Jensen, J. R. & Cowen, D. C. 2011. Remote Sensing of Urban/Suburban Infrastructure
and Socio‐Economic Attributes. The Map Reader: Theories of Mapping Practice and
Cartographic Representation, 153-163.
Jensen, J. R., Hodgson, M. E., Tullis, J. A. & Raber, G. T. 2005. Remote sensing of
impervious surfaces and building infrastructure. Geo-Spatial Technologies in Urban
Environments. Springer.
Jensen, J. R. & Im, J. 2007. Remote sensing change detection in urban environments.
Geo-Spatial Technologies in Urban Environments. Springer.
Jensen, J. R., Rutchey, K., Koch, M. S. & Narumalani, S. 1995. Inland wetland change
detection in the Everglades Water Conservation Area 2A using a time series of
normalized remotely sensed data. Photogrammetric Engineering and Remote Sensing, 61,
199-209.
Jensen, R., Gatrell, J., Boulton, J. & Harper, B. 2004. Using remote sensing and
geographic information systems to study urban quality of life and urban forest amenities.
Ecology and Society, 9, 5.
Jensen, R. R., Boulton, J. R. & Harper, B. T. 2003. The relationship between urban leaf
area and household energy usage in Terre Haute, Indiana, US. Journal of Arboriculture,
29, 226-230.
Jia, K., Wei, X., Gu, X., Yao, Y., Xie, X. & Li, B. 2014. Land cover classification using
Landsat 8 Operational Land Imager data in Beijing, China. Geocarto International, 1-11.
208
Jiang, J. & Tian, G. 2010. Analysis of the impact of land use/land cover change on land
surface temperature with remote sensing. Procedia environmental sciences, 2, 571-575.
Jianya, G., Haigang, S., Guorui, M. & Qiming, Z. 2008. A review of multi-temporal
remote sensing data change detection algorithms. The International Archives of the
Photogrammetry, Remote Sensing and Spatial Information Sciences, 37, 757-762.
Jiménez‐muñoz, J. C. & Sobrino, J. A. 2003. A generalized single‐channel method for
retrieving land surface temperature from remote sensing data. Journal of Geophysical
Research: Atmospheres (1984–2012), 108(D22), 01-09.
Jin, M., Dickinson, R. E. & Zhang, D. 2005. The footprint of urban areas on global
climate as characterized by MODIS. Journal of Climate, 18, 1551-1565.
Jones, P., Trenberth, K., Ambenje, P., Bojariu, R., Easterling, D., Klein, T., Parker, D.,
Renwick, J., Rusticucci, M. & Soden, B. 2007. Observations: surface and atmospheric
climate change. IPCC, Climate change, 235-336.
Joseph, G. 2005. Fundamentals of remote sensing, Universities Press.
Joseph, M., Wang, L. & Wang, F. 2012. Using Landsat imagery and census data for
urban population density modeling in Port-au-Prince, Haiti. GIScience & Remote Sensing,
49, 228-250.
Joshi, J. P., & Bhatt, B. 2012. Estimating temporal land surface temperature using remote
sensing: A study of Vadodara urban area, Gujarat. International Journal of Geology,
Earth and Environmental Sciences, 2(1), 123-130.
Jothimani, P. 1997. Operational urban sprawl monitoring using satellite remote sensing:
excerpts from the studies of Ahmedabad, Vadodara and Surat, India. 18th Asian
conference on remote sensing held during October, 1997. 24.
Vergin, J. 2014. Top 10 worst cities for smog. Agency. Available at:
http://www.dw.com/en/top-10-worst-cities-for-smog/g-17469135 [Accessed 24
November, 2016].
Jusuf, S. K., Wong, N., Hagen, E., Anggoro, R., & Hong, Y. 2007. The influence of land
use on the urban heat island in Singapore. Habitat International, 31(2), 232-242.
209
Jung, M., Henkel, K., Herold, M. & Churkina, G. 2006. Exploiting synergies of global
land cover products for carbon cycle modeling. Remote Sensing of Environment, 101,
534-553.
Kaiser, M., Aboulela, H., EL Serehy, H. & Ezzedin, H. 2010. Spectral enhancement of
SPOT imagery data to assess marine pollution near Port Said, Egypt. International
Journal of Remote Sensing, 31, 1753-1764.
Kalnay, E. & Cai, M. 2003. Impact of urbanization and land-use change on climate.
Nature, 423, 528-531.
Kamishima, K. & Keita, K. 20003. The Analysis of Greening Effects on Urban
Environment Using GIS.
Kantzioura, A., Kosmopoulos, P. & Zoras, S. 2012. Urban surface temperature and
microclimate measurements in Thessaloniki. Energy and Buildings, 44, 63-72.
Kardinal Jusuf, S., Wong, N., Hagen, E., Anggoro, R. & Hong, Y. 2007. The influence of
land use on the urban heat island in Singapore. Habitat International, 31, 232-242.
Karnieli, A., Agam, N., Pinker, R. T., Anderson, M., Imhoff, M. L., Gutman, G. G.,
Panov, N. & Goldberg, A. 2010. Use of NDVI and land surface temperature for drought
assessment: merits and limitations. Journal of Climate, 23, 618-633.
Kataoka, K., Matsumoto, F., Ichinose, T. & Taniguchi, M. 2009. Urban warming trends
in several large Asian cities over the last 100 years. Science of the total environment, 407,
3112-3119.
Kato, S. & Yamaguchi, Y. 2005. Analysis of urban heat-island effect using ASTER and
ETM+ Data: Separation of anthropogenic heat discharge and natural heat radiation from
sensible heat flux. Remote Sensing of Environment, 99, 44-54.
Kato, S. & Yamaguchi, Y. 2007. Estimation of storage heat flux in an urban area using
ASTER data. Remote Sensing of Environment, 110, 1-17.
Katpatal, Y. B., Kute, A. and Satapathy, D. R. 2008. Surface-and air-temperature studies
in relation to land use/land cover of Nagpur urban area using Landsat 5 TM data. Journal
of Urban Planning and Development, 134(3), 110-118.
Katsiabani, K., Adaktilou, N. & Cartalis, C. 2009. A generalized methodology for
estimating land surface temperature for non-urban areas of Greece through the combined
210
use of NOAA–AVHRR data and ancillary information. Advances in Space Research, 43,
930-940.
Kaufmann, R. K. & Seto, K. C. 2001. Change detection, accuracy, and bias in a
sequential analysis of Landsat imagery in the Pearl River Delta, China: econometric
techniques. Agriculture, ecosystems & environment, 85, 95-105.
Kennaway, T. & Helmer, E. 2007. The forest types and ages cleared for land
development in Puerto Rico. GIScience & Remote Sensing, 44, 356-382.
Kerr, Y. H., Lagouarde, J. P., Nerry, F. & Ottlé, C. 2004. Land surface temperature
retrieval techniques and applications. Thermal remote sensing in land surface processes,
CRC Press, Boston, USA, 33-109.
Khan, A. A., Arshad, S. & Mohsin, M. 2014. Population growth and its impact on urban
expansion: A case study of Bahawalpur, Pakistan. Universal Journal of Geoscience, 2,
229-241.
Kidder, S. Q. & Essenwanger, O. M. 1995. The effect of clouds and wind on the
difference in nocturnal cooling rates between urban and rural areas. Journal of Applied
Meteorology, 34, 2440-2448.
Kifle, B. 2003. Urban heat island and its feature in Addis Ababa (a case study). Paper
presented at the Fifth International Conference on Urban Climate.
http://nargeo.geo.uni.lodz.pl/~icuc5/text/P_6_11.pdf [Accessed 14 Aug 2013].
Kim, Y. H. and Baik, J. J. 2002. Maximum urban heat island intensity in Seoul. Journal
of Applied Meteorology, 41, 651-659.
Kit, O., Lüdeke, M. & Reckien, D. 2012. Texture-based identification of urban slums in
Hyderabad, India using remote sensing data. Applied Geography, 32, 660-667.
Keramitsoglou, I., Kiranoudis, C. T., Ceriola, G., Weng, Q., & Rajasekar, U. 2011.
Identification and analysis of urban surface temperature patterns in Greater Athens,
Greece, using MODIS imagery. Remote sensing of environment, 115(12), 3080-3090.
Knight, J. F., Lunetta, R. S., Ediriwickrema, J. & Khorram, S. 2006. Regional scale land
cover characterization using MODIS-NDVI 250 m multi-temporal imagery: A
phenology-based approach. GIScience & Remote Sensing, 43, 1-23.
211
Kohli, D., Sliuzas, R., Kerle, n. & Stein, A. 2012. An ontology of slums for image-based
classification. Computers, Environment and Urban Systems, 36, 154-163.
Kolokotroni, M., Giannitsaris, I. & Watkins, R. 2006. The effect of the London urban
heat island on building summer cooling demand and night ventilation strategies. Solar
Energy, 80, 383-392.
Kottmeier, C., Biegert, C. and Corsmeier, U. 2007. Effects of urban land use on surface
temperature in Berlin: Case study. Journal of urban planning and development, 133(2),
128-137.
Kumar, K. S., Bhaskar, P. U., & Padmakumari, K. 2012. Estimation of land surface
temperature to study urban heat island effect using Landsat ETM+ image. International
Journal of Engineering Science, 4, 771-778.
Kustas, W. & Anderson, M. 2009. Advances in thermal infrared remote sensing for land
surface modeling. Agricultural and Forest Meteorology, 149, 2071-2081.
Kuttler, W. 2008. The urban climate–basic and applied aspects. Urban ecology. Springer.
Lambin, E. F., Turner, B. L., Geist, H. J., Agbola, S. B., Angelsen, A., Bruce, J. W.,
Coomes, O. T., Dirzo, R., Fischer, G. & Folke, C. 2001. The causes of land-use and land-
cover change: moving beyond the myths. Global environmental change, 11, 261-269.
Landsberg, H. E. 1981. The urban climate, Academic press.
Lata, K. M., Sankar Rao, C., Krishna Prasad, V., Badrinath, K. & Raghavaswamy, V.
2001. Measuring urban sprawl: a case study of Hyderabad. GIS development, 5.
Li, B., Yu, W. & Wang, J. 2011. An Analysis of Vegetation Change Trends and Their
Causes in Inner Mongolia, China from 1982 to 2006. Advances in Meteorology, 2011.
Li, K., Lin, B. and Jiang, D. 2012. A New Urban Planning Approach for Heat Island
Study at the Community Scale. J. Heat Isl. Inst. Int, 7, 50-54.
Li, L., Sato, Y. & Zhu, H. 2003. Simulating spatial urban expansion based on a physical
process. Landscape and urban planning, 64, 67-76.
Li, X., Ma, Y., Xu, H., Wang, J. & Zhang, D. 2009. Impact of land use and land cover
change on environmental degradation in Lake Qinghai watershed, northeast Qinghai-
Tibet Plateau. Land Degradation and Development, 20, 69.
212
Li, X. & Yeh, A. 1998. Principal component analysis of stacked multi-temporal images
for the monitoring of rapid urban expansion in the Pearl River Delta. International
Journal of Remote Sensing, 19, 1501-1518.
Li, Y.-Y., Zhang, H. & Kainz, W. 2012. Monitoring patterns of urban heat islands of the
fast-growing Shanghai metropolis, China: Using time-series of Landsat TM/ETM+ data.
International Journal of Applied Earth Observation and Geoinformation, 19, 127-138.
Li, Z.-L., Tang, B.-H., Wu, H., Ren, H., Yan, G., Wan, Z., Trigo, I. F. & Sobrino, J. A.
2013. Satellite-derived land surface temperature: Current status and perspectives. Remote
Sensing of Environment, 131, 14-37.
Liang, S. 2008. Advances in land remote sensing: system, modeling, inversion and
application, Springer.
Liang, B. and Weng, Q. 2008. Multiscale analysis of census-based land surface
temperature variations and determinants in Indianapolis, United States. Journal of Urban
Planning and Development, 134(3), 129-139.
Lillesand, T., Kieffer, R. W. & Chipman, J. 2007. Remote Sensing and Image
Interpretation, John Wiley and Sons, New York, US.
Lillesand, T. M., Kiefer, R. W., & Chipman, J. W. 2004. Remote sensing and image
interpretation: John Wiley & Sons Ltd.
Liu, H. & Weng, Q. 2008. Seasonal variations in the relationship between landscape
pattern and land surface temperature in Indianapolis, USA. Environmental monitoring
and assessment, 144, 199-219.
Liu, J., Zhuang, D., Luo, D. & Xiao, X. M. 2003. Land-cover classification of China:
integrated analysis of AVHRR imagery and geophysical data. International Journal of
Remote Sensing, 24, 2485-2500.
Liu, L. & Zhang, Y. 2011. Urban heat island analysis using the Landsat TM data and
ASTER data: A case study in Hong Kong. Remote Sensing, 3, 1535-1552.
Liu, W., Ji, C., Zhong, J., Jiang, X. & Zheng, Z. 2007. Temporal characteristics of the
Beijing urban heat island. Theoretical and Applied Climatology, 87, 213-221.
Liu, X. & Herold, M. 2007. Population estimation and interpolation using remote sensing.
Urban remote sensing, 269-290.
213
Liu, X. & Lathrop JR, R. 2002. Urban change detection based on an artificial neural
network. International Journal of Remote Sensing, 23, 2513-2518.
Liu, Y., Gao, J. & Yang, Y. 2003. A holistic approach towards assessment of severity of
land degradation along the Great Wall in northern Shaanxi Province, China.
Environmental Monitoring and Assessment, 82, 187-202.
Lo, C. P., Quattrochi, D. A. & Luvall, J. C. 1997. Application of high-resolution thermal
infrared remote sensing and GIS to assess the urban heat island effect. International
Journal of Remote Sensing, 18, 287-304.
Lu, D. & Weng, Q. 2007. A survey of image classification methods and techniques for
improving classification performance. International journal of Remote sensing, 28, 823-
870.
Lulla, K., Duane Nellis, M. & Rundquist, B. 2013. The Landsat 8 is ready for geospatial
science and technology researchers and practitioners. Geocarto International, 28, 191-
191.
Lwin, K. K. & Murayama, Y. 2011. Modelling of urban green space walkability: Eco-
friendly walk score calculator. Computers, Environment and Urban Systems, 35, 408-420.
MA, Y., Kuang, Y. & Huang, N. 2010. Coupling urbanization analyses for studying
urban thermal environment and its interplay with biophysical parameters based on
TM/ETM+ imagery. International Journal of Applied Earth Observation and
Geoinformation, 12, 110-118.
Mahmood, R., Foster, S. A. & Logan, D. 2006. The GeoProfile metadata, exposure of
instruments, and measurement bias in climatic record revisited. International journal of
climatology, 26, 1091-1124.
Maimaitiyiming, M., Ghulam, A., Tiyip, T., Pla, F., Latorre-Carmona, P., Halik, Ü,
Sawut, M. & Caetano, M. 2014. Effects of green space spatial pattern on land surface
temperature: Implications for sustainable urban planning and climate change adaptation.
ISPRS Journal of Photogrammetry and Remote Sensing, 89, 59-66.
Maki, M., Ishiahra, M., & Tamura, M. 2004. Estimation of leaf water status to monitor
the risk of forest fires by using remotely sensed data. Remote sensing of Environment,
90(4), 441-450.
214
Maktav, D., Erbek, F. & Jürgens, C. 2005. Remote sensing of urban areas. International
Journal of Remote Sensing, 26, 655-659.
Maktav, D., & Erbek, F. 2005. Analysis of urban growth using multi‐temporal satellite
data in Istanbul, Turkey. International Journal of Remote Sensing, 26(4), 797-810.
Mallick, J. 2014. Land Characterization Analysis of Surface Temperature of Semi-Arid
Mountainous City Abha, Saudi Arabia Using Remote Sensing and GIS. Journal of
Geographic Information System, 6(6), 664-676.
Mallick, J., Kant, Y., & Bharath, B. 2008. Estimation of land surface temperature over
Delhi using Landsat-7 ETM+. J Indian Geophysics Union, 12(3), 131-140.
Mandelas, E. A., Hatzichristos, T. & Prastacos, P. 2007. A fuzzy cellular automata based
shell for modeling urban growth–a pilot application in Mesogia area. 10th AGILE
International Conference on Geographic Information Science, Aalborg University,
Denmark, 1-9.
Mao, Y., Ye, A. & Xu, J. 2012. Using Land Use Data to Estimate the Population
Distribution of China in 2000. GIScience & Remote Sensing, 49, 822-853.
Masson, V. 2006. Urban surface modeling and the meso-scale impact of cities.
Theoretical and Applied Climatology, 84, 35-45.
Mandelas, E. A., Hatzichristos, T., & Prastacos, P. 2007. A fuzzy cellular automata based
shell for modeling urban growth–a pilot application in Mesogia area. Paper presented at
the 10th AGILE International Conference on Geographic Information Science, Aalborg
University, Denmark.
Markham, B. & Barker, J. 1987. Thematic Mapper band pass solar exoatmospheric
irradiances. International Journal of Remote Sensing, 8, 517-523.
Matinfar, H. R., Sarmadian, F., Alavi panah, S. K. & Heck, R. J. 2007. Comparisons of
Object-Oriented and Pixel-Based Classification of Land Use/Land Cover Types Based on
Lansadsat7, Etm+ Spectral Bands (Case Study: Arid Region of Iran. American-Eurasian
J. Agric. & Environ. Sci., 2 (4), 448-456.
Mayunga, S., Coleman, D. & Zhang, Y. 2007. A semi‐automated approach for extracting
buildings from Quick Bird imagery applied to informal settlement mapping. International
Journal of Remote Sensing, 28, 2343-2357.
215
Mcfeeters, S. 1996. The use of the Normalized Difference Water Index (NDWI) in the
delineation of open water features. International journal of remote sensing, 17, 1425-
1432.
Meng, C., Li, Z. L., Zhan, X., Shi, J. & Liu, C. 2009. Land surface temperature data
assimilation and its impact on evapotranspiration estimates from the Common Land
Model. Water resources research, 45.
Mesev, T., Longley, P. A., Batty, M. & Xie, Y. 1995. Morphology from imagery:
detecting and measuring the density of urban land use. Environment and Planning A, 27,
759-780.
Miller, S. N., Phillip Guertin, D. & Goodrich, D. C. 2007. Hydrologic Modeling
Uncertainty Resulting From Land Cover Misclassification1. Wiley Online Library.
Mitchell, M. & Yuan, F. 2010. Assessing forest fire and vegetation recovery in the Black
Hills, South Dakota. GIScience & Remote Sensing, 47, 276-299.
Mohan, M., Kikegawa, Y., Gurjar, B., Bhati, S., & Kolli, N. R. 2013. Assessment of
urban heat island effect for different land use–land cover from micrometeorological
measurements and remote sensing data for megacity Delhi. Theoretical and Applied
Climatology, 1-12.
Mohan, M., Pathan, S. K., Narendrareddy, K., Kandya, A. & Pandey, S. 2011. Dynamics
of urbanization and its impact on land-use/land-cover: A case study of megacity delhi.
Journal of Environmental Protection, 2, 1274.
Mohsin, M., Arshad, S. and Khan, A.A. 2014. Population Growth and Its Impact on
Urban Expansion: A Case Study of Bahawalpur, Pakistan. Universal Journal of
Geoscience. 2(8): 229-241.
Moran, M., Scott, R., Keefer, T., Emmerich, W., Hernandez, M., Nearing, G., Paige, G.,
Cosh, M. & O’Neill, P. 2009. Partitioning evapotranspiration in semiarid grassland and
shrub land ecosystems using time series of soil surface temperature. Agricultural and
forest meteorology, 149, 59-72.
Moran, M. S. 2004. Thermal infrared measurement as an indicator of planet ecosystem
health. Thermal remote sensing in land surface processes, 257-282.
216
Moreno‐Garcia, M. C. 1994. Intensity and form of the urban heat island in Barcelona.
International Journal of Climatology, 14, 705-710.
Mundia, C., & Aniya, M. 2005. Analysis of land use/cover changes and urban expansion
of Nairobi city using remote sensing and GIS. International Journal of Remote Sensing,
26(13), 2831-2849.
Muñoz‐Villers, L. & López‐Blanco, J. 2008. Land use/cover changes using Landsat
TM/ETM images in a tropical and bio diverse mountainous area of central‐eastern
Mexico. International Journal of Remote Sensing, 29, 71-93.
Muttitanon, W. & Tripathi, N. 2005. Land use/land cover changes in the coastal zone of
Ban Don Bay, Thailand using Landsat 5 TM data. International Journal of Remote
Sensing, 26, 2311-2323.
Myneni, R. B., Dong, J., Tucker, C., Kaufmann, R., Kauppi, P., Liski, J., Zhou, L.,
Alexeyev, V. & Hughes, M. 2001. A large carbon sink in the woody biomass of northern
forests. Proceedings of the National Academy of Sciences, 98, 14784-14789.
Nadoushan, M. A., Soffianian, A. & Alebrahim, A. 2012. Predicting Urban Expansion in
Arak Metropolitan Area Using Two Land Change Models. World Applied Sciences
Journal, 18, 1124-1132.
Nagendra, H., Munroe, D. K. & Southworth, J. 2004. From pattern to process: landscape
fragmentation and the analysis of land use/land cover change. Agriculture, Ecosystems &
Environment, 101, 111-115.
NASA. 2000. Land Surface Temperature [Online]. Available:
http://earthobservatory.nasa.gov/GlobalMaps/view.php?d1=MOD11C1_M_LSTDA
[Accessed 20 DEC 2014].
NESPAK 2004. Integrated Master Plan for Lahore-2021; Final Report Volume 1 Existing
Scenario, National Engineering Services Pakistan (Pvt.) Ltd. Lahore, Punjab Pakistan.
Nichol, J. E. 1994. Modelling the relationship between LANDSAT TM thermal data and
urban morphology. Paper presented at the Proceedings of ACMS/ASPRS Annual
Convention and Exposition, Baltimore, United States.
Nichol, J. 2005. Remote sensing of urban heat islands by day and night. Photogrammetric
Engineering & Remote Sensing, 71(5), 613-621.
217
Nichol, J. 2009. Remote sensing of urban areas, Sage Publications: Thousand Oaks, CA,
USA.
Nichol, J. E., Fung, W. Y., Lam, K.-S. & Wong, M. S. 2009. Urban heat island diagnosis
using ASTER satellite images and ‘in situ air temperature. Atmospheric Research, 94,
276-284.
Nichol, J. E. & Wong, M. S. 2006. Assessing urban environmental quality with multiple
parameters. Urban remote sensing, 253-268.
Nieuwolt, S. 1966. The urban microclimate of Singapore. Journal of Tropical Geography,
22, 30-37.
Nonomura, A., Kitahara, M. & Masuda, T. 2009. Impact of land use and land cover
changes on the ambient temperature in a middle scale city, Takamatsu, in Southwest
Japan. Journal of environmental management, 90, 3297-3304.
Nuruzzaman, M. 2015. Urban Heat Island: Causes, Effects and Mitigation Measures-A
Review. International Journal of Environmental Monitoring and Analysis, 3, 67.
OECD 2010. Cities and Climate Change, OECD publishing. Available at:
http://dx.doi.org/10.1787/9789264091375-en [Accessed 23 August, 2014].
Oke, T. R. 1982. The energetic basis of the urban heat island. Quarterly Journal of the
Royal Meteorological Society, 108, 1-24.
Oke, T. R. 1987. Boundary layer climates, Psychology Press.
Oke, T. R. 1992. Boundary layer climates (Vol. 5): Psychology Press.
Ooka, R. 2007. Recent development of assessment tools for urban climate and heat‐island
investigation especially based on experiences in Japan. International Journal of
Climatology, 27(14), 1919-1930.
Okwen, R., PU, R. and Cunningham, J. 2011. Remote sensing of temperature variations
around major power plants as point sources of heat. International journal of remote
sensing, 32(13), 3791-3805.
Owen, T., Carlson, T. and Gillies, R. 1998. An assessment of satellite remotely-sensed
land cover parameters in quantitatively describing the climatic effect of urbanization.
International Journal of Remote Sensing, 19, 1663-1681.
218
Parker, D. E. 2006. A demonstration that large-scale warming is not urban. Journal of
climate, 19, 2882-2895.
Parry, M. L. 2007. Climate change 2007-impacts, adaptation and vulnerability: Working
group II contribution to the fourth assessment report of the IPCC, Cambridge University
Press.
Pease, R. W., Lewis, J. E. & Outcalt, S. I. 1976. Urban terrain climatology and remote
sensing. Annals of the Association of American Geographers, 66, 557-568.
Peng, S.-S., Piao, S., Zeng, Z., Ciais, P., Zhou, L., Li, L. Z., Myneni, R. B., Yin, Y. &
Zeng, H. 2014. Afforestation in China cools local land surface temperature. Proceedings
of the National Academy of Sciences, 111, 2915-2919.
Phinn, S., Stanford, M., Scarth, P., Murray, A. & Shyy, P. 2002. Monitoring the
composition of urban environments based on the vegetation-impervious surface-soil
(VIS) model by subpixel analysis techniques. International Journal of Remote Sensing,
23, 4131-4153.
Pielke, R. A., Marland, G., Betts, R. A., Chase, T. N., Eastman, J. L., Niles, J. O., &
Running, S. W. 2002. The influence of land-use change and landscape dynamics on the
climate system: relevance to climate-change policy beyond the radiative effect of
greenhouse gases. Philosophical Transactions of the Royal Society of London. Series A:
Mathematical, Physical and Engineering Sciences, 360(1797), 1705-1719.
Pinho, O. and Orgaz, M. M. 2000. The urban heat island in a small city in coastal
Portugal. International Journal of biometeorology, 44(35), 198-203.
Pongracz, R., Bartholy, J. & Dezso, Z. 2006. Remotely sensed thermal information
applied to urban climate analysis. Advances in Space Research, 37, 2191-2196.
Prasad, A. D., Jain, K. & Gairola, A. 2013. Surface Temperature Estimation using
Landsat Data for part of the Godavari and Tapi Basins, India: A Case Study. International
Journal of Engineering and Advanced Technology (IJEAT), 2(3), 320-322.
PRB., 2013. World Population Data Sheet: Population Reference Bureau.
Priyadarsini, R., Hien, W. N. & David, C. K. W. 2008. Microclimatic modeling of the
urban thermal environment of Singapore to mitigate urban heat island. Solar energy, 82,
727-745.
219
Pu, R., Gong, P., Michishita, R. & Sasagawa, T. 2006. Assessment of multi-resolution
and multi-sensor data for urban surface temperature retrieval. Remote Sensing of
Environment, 104, 211-225.
Puertas, O., Henríquez, C. & Meza, F. 2010. Assessing spatial dynamics of urban growth
using an integrated land use model. Application in Santiago Metropolitan Area, 2045,
415-425.
Puertas, O. L., Henríquez, C. & Meza, F. J. 2014. Assessing spatial dynamics of urban
growth using an integrated land use model. Application in Santiago Metropolitan Area,
2010–2045. Land Use Policy, 38, 415-425.
Purevdorj, T., Tateishi, R., Ishiyama, T., & Honda, Y. 1998. Relationships between
percent vegetation cover and vegetation indices. International Journal of Remote Sensing,
19(18), 3519-3535.
Qin, Z., Dall'olmo, G., Karnieli, A. & Berliner, P. 2001. Derivation of split window
algorithm and its sensitivity analysis for retrieving land surface temperature from
NOAA‐advanced very high resolution radiometer data. Journal of Geophysical Research:
Atmospheres (1984–2012), 106, 22655-22670.
Qin, Z.-H., Karnieli, A. & Berliner, P. 2001. A mono-window algorithm for retrieving
land surface temperature from Landsat TM data and its application to the Israel-Egypt
border region. International Journal of Remote Sensing, 22, 3719-3746.
Quattrochi, D. & Luvall, J. 1999. High spatial resolution airborne multispectral thermal
infrared data to support analysis and modeling tasks in the EOS IDS Project Atlanta.
URL: http://wwwghcc. msfc. nasa. gov/atlanta/, Global Hydrology and Climate center,
NASA, Huntsville, Alabama (last date accessed: 1 June 2003).
Quattrochi, D. A. & Luvall, J. C. 1999. Thermal infrared remote sensing for analysis of
landscape ecological processes: methods and applications. Landscape ecology, 14, 577-
598.
Qureshi, J., Mahmood, S. A., Almas, A. S., Rafique, H. M., & Irshad, R. 2012.
Monitoring spatiotemporal and micro-level climatic variations in Lahore and subrubs
using satellite imagery and multi-source data. Journal of Faculty of Engineering &
Technology, 19(1), 53-68.
220
Rajasekar, U. & Weng, Q. 2009. Urban heat island monitoring and analysis using a non-
parametric model: A case study of Indianapolis. ISPRS Journal of Photogrammetry and
remote sensing, 64, 86-96.
Rajasekar, U. & Weng, Q. 2009. Spatio‐temporal modelling and analysis of urban heat
islands by using Landsat TM and ETM+ imagery. International Journal of Remote
Sensing, 30, 3531-3548.
Rajeshwari, A. & Mani, N. 2014. Estimation of land surface temperature of din Digul
district using Landsat 8 data. IJRET: International Journal of Research in Engineering and
Technology, 3(5), 122-126.
Rao, P. 1972. Remote sensing of urban heat islands from an environmental satellite.
Amer Meteorological SOC 45 Beacon St, Boston, MA 02108-3693.
Rashed, T., Weeks, J., Couclelis, H. & Herold, M. 2007. An integrative GIS and remote
sensing model for place-based urban vulnerability analysis. Integration of GIS and remote
sensing. Wiley, Chichester, 199-224.
Ratanopad, S. & Kainz, W. 2006. Land cover classification and monitoring in northeast
Thailand using landsat5 TM data. ISPRS Technical Commission II Symposium, Vienna.
Reis, S. 2008. Analyzing land use/land cover changes using remote sensing and GIS in
Rize, North-East Turkey. Sensors, 8, 6188-6202.
Retalis, A., Paronis, D., Lagouvardos, K. & Kotroni, V. 2010. The heat wave of June
2007 in Athens, Greece—Part 1: Study of satellite derived land surface temperature.
Atmospheric Research, 98, 458-467.
Riaz, O. 2012. Impact of Population Growth on Urban Expansion in Lahore, 1951-1998.
PhD thesis (Unpublished), University of the Punjab, Lahore, Pakistan.
Richards, J. A. & Richards, J. 1999. Remote sensing digital image analysis, Springer.
Rinner, C. and Hussain, M. 2011. Toronto’s urban heat island—exploring the relationship
between land use and surface temperature. Remote Sensing, 3, 1251-1265.
Rizwan, A. M., Dennis, L. Y. & Liu, C. 2008. A review on the generation, determination
and mitigation of Urban Heat Island. Journal of Environmental Sciences, 20, 120-128.
221
Rosenzweig, C., Solecki, W. D., Hammer, S. A. & Mehrotra, S. 2011. Climate change
and cities: first assessment report of the Urban Climate Change Research Network ,
Cambridge University Press.
Roth, M. 2000. Review of atmospheric turbulence over cities. Quarterly Journal of the
Royal Meteorological Society, 126, 941-990.
Roth, M. 2002. Urban heat island dynamics in Singapore.
Roth, M., Oke, T. & Emery, W. 1989. Satellite-derived urban heat islands from three
coastal cities and the utilization of such data in urban climatology. International Journal
of Remote Sensing, 10, 1699-1720.
Rozenstein, O., Qin, Z., Derimian, Y. & Karnieli, A. 2014. Derivation of Land Surface
Temperature for Landsat-8 TIRS Using a Split Window Algorithm. Sensors, 14, 5768-
5780.
Ruiliang, P. u., Gong, P., Michishita, R., & Sasagawa, T. 2006. Assessment of multi-
resolution and multi-sensor data for urban surface temperature retrieval. Remote sensing
of environment, 104(2), 211-225.
Running, S. W. 2008. Ecosystem disturbance, carbon, and climate. Science, 321, 652-
653.
Saaroni, H., Ben-dor, E., Bitan, A. and Potchter, O. 2000. Spatial distribution and micro
scale characteristics of the urban heat island in Tel-Aviv, Israel. Landscape and Urban
Planning, 48, 1-18.
Sadidy, J., Firouzabadi, P. & Entezari, A. 2005. The use of radar sat and Landsat image
fusion algorithms and different supervised classification methods to improve land use
map accuracy–case study: sari plain–Iran. Department of Geography, Tarbiat Moallem
Sabzevar University.
Şahin, M., Yıldız, B. Y., Şenkal, O. & Peştemalcı, V. 2012. Modelling and remote
sensing of land surface temperature in Turkey. Journal of the Indian Society of Remote
Sensing, 40, 399-409.
Sajjad, S., Shirazi, S. A., Ahmed Khan, M. & Raza, A. 2009. Urbanization effects on
temperature trends of Lahore during 1950-2007. International Journal of Climate Change
Strategies and Management, 1(3), 274-281.
222
Sajjad, S. H. 2013. Observational and modelling approaches to study urban climate:
application on Pakistan. PhD thesis (Unpublished), Université de Strasbourg.
Sajjad, S. H., Batool, R., Qadri, S. T., Shirazi, S. A. & Shakrullah, K. 2015. The long-
term variability in minimum and maximum temperature trends and heat island of Lahore
city, Pakistan. Science International, 27.
Sameen, M. I. & AL Kubaisy, M. A. 2014. Automatic surface temperature mapping in
arcgis using landsat-8 tirs and envi tools, case study: Al Habbaniyah Lake. J. Environ.
Earth Sci, 4, 12-17.
Santamouris, M., Paraponiaris, K. and Mihalakakou, G. 2007. Estimating the ecological
footprint of the heat island effect over Athens, Greece. Climatic Change, 80, 265-276.
Schmidt, H. & Karnieli, A. 2000. Remote sensing of the seasonal variability of vegetation
in a semi-arid environment. Journal of Arid Environments, 45, 43-59.
Schmugge, T., Hook, S. & Coll, C. 1998. Recovering surface temperature and emissivity
from thermal infrared multispectral data. Remote Sensing of Environment, 65, 121-131.
Schroeder, T. A., Cohen, W. B., Song, C., Canty, M. J. & YAng, Z. 2006. Radiometric
correction of multi-temporal Landsat data for characterization of early successional forest
patterns in western Oregon. Remote Sensing of Environment, 103, 16-26.
Schwarz, N., Lautenbach, S. & Seppelt, R. 2011. Exploring indicators for quantifying
surface urban heat islands of European cities with MODIS land surface temperatures.
Remote Sensing of Environment, 115, 3175-3186.
Seber, G. A., & Lee, A. J. 2012. Linear regression analysis (Vol. 936): John Wiley &
Sons.
Seto, K. C. & Shepherd, J. M. 2009. Global urban land-use trends and climate impacts.
Current Opinion in Environmental Sustainability, 1, 89-95.
Seto, K. C., Woodcock, C., Song, C., Huang, X., Lu, J. & Kaufmann, R. 2002.
Monitoring land-use change in the Pearl River Delta using Landsat TM. International
Journal of Remote Sensing, 23, 1985-2004.
Shalaby, A. & Tateishi, R. 2007. Remote sensing and GIS for mapping and monitoring
land cover and land-use changes in the Northwestern coastal zone of Egypt. Applied
Geography, 27, 28-41.
223
Shekhar, S. 2007. Changing Space of Pune–A GIS perspective GIS@ development
MapWorld Form, Hyderabad, India. Paper Ref NO: MWF PN, 116.
Shenghe, L., Prieler, S., & Xiubin, L. 2002. Spatial patterns of urban land use growth in
Beijing. Journal of Geographical Sciences, 12(3), 266-274.
Shirazi, S. A. 2011. Urban Development and its impact on the Vegetation of Lahore. PhD
Thesis (Unpublished) University of Karachi, Karachi, Pakistan.
Shudo, H., Sugiyama, J., Yokoo, N. and Oka, T. 1997. A study on temperature
distribution influenced by various land uses. Energy and buildings, 26, 199-205.
Shukla, J. & Mintz, Y. 1982. Influence of land-surface evapotranspiration on the earth's
climate. Science, 215, 1498-1501.
Stathopoulou, M., & Cartalis, C. 2009. Downscaling AVHRR land surface temperatures
for improved surface urban heat island intensity estimation. Remote sensing of
environment, 113(12), 2592-2605.
Sobrino, J. A., Jiménez-Muñoz, J. C. & Paolini, L. 2004. Land surface temperature
retrieval from LANDSAT TM 5. Remote Sensing of environment, 90, 434-440.
Sobrino, J. A., Jiménez-Muñoz, J. C., Sòria, G., Romaguera, M., Guanter, L., Moreno, J.,
Plaza, A. & Martínez, P. 2008. Land surface emissivity retrieval from different VNIR and
TIR sensors. IEEE Transactions on Geoscience and Remote Sensing, 46, 316-327.
Son, N., Chen, C., Chen, C., Chang, L. & Minh, V. 2012. Monitoring agricultural drought
in the Lower Mekong Basin using MODIS NDVI and land surface temperature data.
International Journal of Applied Earth Observation and Geoinformation, 18, 417-427.
Stemn, E. 2014. Assessment of Urban Expansion and Its Effect on Surface Temperature
in the Sekondi-Takoradi Metropolis of Ghana–A Remote Sensing and GIS Approach.
Stohlgren, T. J., Chase, T. N., Pielke, R. A., Kittel, T. G. and Baron, J. 1998. Evidence
that local land use practices influence regional climate, vegetation, and stream flow
patterns in adjacent natural areas. Global Change Biology, 4, 495-504.
Stone JR, B. & Rodgers, M. O. 2001. Urban form and thermal efficiency: How the design
of cities influences the urban heat island effect. Journal of the American Planning
Association, 67, 186-198.
224
Streutker, D. R. 2002. A remote sensing study of the urban heat island of Houston, Texas.
International Journal of Remote Sensing, 23(13), 2595-2608.
Streutker, D. R. 2003. Satellite-measured growth of the urban heat island of Houston,
Texas. Remote Sensing of Environment, 85, 282-289.
Sudhira, H., Ramachandra, T. & Jagadish, K. 2004. Urban sprawl: metrics, dynamics and
modelling using GIS. International Journal of Applied Earth Observation and
Geoinformation, 5, 29-39.
Sun, Q., Tan, J. & Xu, Y. 2010. An ERDAS image processing method for retrieving LST
and describing urban heat evolution: a case study in the Pearl River Delta Region in
South China. Environmental Earth Sciences, 59, 1047-1055.
Sun, Q., Wu, Z. & Tan, J. 2012. The relationship between land surface temperature and
land use/land cover in Guangzhou, China. Environmental Earth Sciences, 65, 1687-1694.
Sun, Z., Ma, R. & Wang, Y. 2009. Using Landsat data to determine land use changes in
Datong basin, China. Environmental geology, 57, 1825-1837.
Sun, Q., Tan, J., & Xu, Y. 2010. An ERDAS image processing method for retrieving LST
and describing urban heat evolution: a case study in the Pearl River Delta Region in
South China. Environmental Earth Sciences, 59(5), 1047-1055.
Takeuchi, W., Hashim, N., & Thet, K. M. 2010. Application of remote sensing and GIS
for monitoring urban heat island in Kuala Lumpur Metropolitan area. Paper presented at
the Map Asia 2010 and the International Symposium and Exhibition on Geoinformation,
Kuala Lumpur. http://ismwiki.vms.my/images/9/9e/306_mapasia2010.pdf [Accessed 14
Aug 2 013].
Tan, K. C., San Lim, H., Matjafri, M. Z. & Abdullah, K. 2010. Landsat data to evaluate
urban expansion and determine land use/land cover changes in Penang Island, Malaysia.
Environmental Earth Sciences, 60, 1509-1521.
Taha, H. 1997. Urban climates and heat islands: albedo, evapotranspiration, and
anthropogenic heat. Energy and buildings, 25, 99-103.
Taubenböck, H., Wegmann, M., Berger, C., Breunig, M., Roth, A. & Mehl, H. 2008.
Spatiotemporal analysis of Indian mega cities. Proceedings of the international archives
225
of the photogrammetry, remote sensing and spatial information sciences (ISPRS), 37, 75-
82.
Thenkabail, P. S., Biradar, C. M., Noojipady, P., Dheeravath, V., LI, Y., Velpuri, M.,
Gumma, M., Gangalakunta, O. R. P., Turral, H. & Cai, X. 2009. Global irrigated area
map (GIAM), derived from remote sensing, for the end of the last millennium.
International Journal of Remote Sensing, 30, 3679-3733.
Thi Van, T. & Duong xuan Bao, H. 2010. Study of the impact of urban development on
surface temperature using remote sensing in Ho Chi Minh City, northern Vietnam.
Geographical Research, 48, 86-96.
Tian, Q. & Min, X.-J. 1998. Advances in study on vegetation indices. Advance Earth
Science, 13, 327-333.
Townshend, J. R., Masek, J. G., Huang, C., Vermote, E. F., Gao, F., Channan, S., Sexton,
J. O., Feng, M., Narasimhan, R. & Kim, D. 2012. Global characterization and monitoring
of forest cover using Landsat data: opportunities and challenges. International Journal of
Digital Earth, 5, 373-397.
Tran, H., Uchihama, D., Ochi, S. & Yasuoka, Y. 2006. Assessment with satellite data of
the urban heat island effects in Asian mega cities. International Journal of Applied Earth
Observation and Geoinformation, 8, 34-48.
Turner, I., Bl, C., Wc, K., Rw, R., Jf, M., & Jt, M. WB (Eds.), 1990. The Earth as
Transformed by Human Action: Global and Regional Changes in the Biosphere over the
Past 300 Years: Cambridge University Press, Cambridge.
Trenberth, K. E. 1992. Climate system modeling, Cambridge University Press.
Trenberth, K. E. 2004. Climatology (communication arising): rural land-use change and
climate. Nature, 427, 213-213.
Trenberth, K.E., P.D. Jones, P. Ambenje, R. Bojariu, D. Easterling, A. Klein Tank, D.
Parker, F. Rahimzadeh, J.A. Renwick, M. Rusticucci, B. Soden and P. Zhai. 2007.
Observations: surface and atmospheric Climate Change. In: climate change 2007: the
physical science basis. Contribution of working group I to the forth assessment report of
the intergovernmental panel on climate change [Solomon, S., D. Qin, M. Manning, Z.
Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge
University Press, Cambridge, United Kingdom and New York, Ny, USA.
226
Tursilowati, L., Tetuko Sri Sumantyo, J., Kuze, H. & Adiningsih, E. S. 2012.
Relationship between urban heat island phenomenon and land use/land cover changes in
Jakarta-Indonesia. Journal of Emerging Trends in Engineering and Applied Sciences, 3,
645-653.
UN. 2004. World urbanization prospects: the 2003 revision. New York: Population
division, Department of Economic and Social Affairs, United Nations, ESA/P/WP/215.
UN, 2005. World Urbanization Prospects: The 2005 Revision. New York: Department of
Economic and Social Affairs: Population Division.
UN. 2008. World Urbanization Prospects, The 2007 Revision [Online]. United Nations,
New York, Available:
http://www.un.org/esa/population/publications/wup2007/2007WUP_Highlights_web.pdf
[Accessed 23 DEC 2014].
UN. 2009. World population prospects the 2008 revision and world urbanization
prospects. New York: Population Division, Department of Economic and Social Affairs,
United Nations.
UN. 2010. World urbanization prospects the 2009 revision highlights. New York:
Population division, Department of Economic and Social Affairs, United Nations,
ESA/P/WP/215.
UN. 2014. World urbanization prospects the 2014 revision highlights. New York:
Population division, Department of Economic and Social Affairs, United Nations.
UN. 2015. World urbanization prospects the 2015 revision highlights. New York:
Population division, Department of Economic and Social Affairs, United Nations.
USGS, 2001. Landsat 7 Science Data User’s Handbook.
http://landsathandbook.gsfc.nasa.gov/pdfs/Landsat7_Handbook.pdf
USGS, 2015. Landsat 8 (L8) Data users handbook.
https://landsat.usgs.gov/documents/Landsat8DataUsersHandbook.pdf
Van, T. T., & Bao, H. D. X. 2010. Study of the impact of urban development on surface
temperature using remote sensing in Ho Chi Minh City, northern Vietnam. Geographical
Research, 48(1), 86-96.
227
Vinnikov, K. Y., Yu, Y., Goldberg, M. D., Chen, M. & Tarpley, D. 2011. Scales of
temporal and spatial variability of midlatitude land surface temperature. Journal of
Geophysical Research: Atmospheres (1984–2012), 116.
Viterito, A. 1991. Future warming for US cities. Population and Environment, 13(2),
101-111.
Voogt, J. A., & Oke, T. R. 1998. Effects of urban surface geometry on remotely-sensed
surface temperature. International Journal of Remote Sensing, 19(5), 895-920.
Voogt, J. A., & Oke, T. R. 2003. Thermal remote sensing of urban climates. Remote
sensing of environment, 86(3), 370-384.
Wan, Z. 2007. Collection-5 MODIS Land Surface Temperature Products Users' Guide.
ICESS, University of California, Santa Barbara.
Wan, Z., Wang, P. & Li, X. 2004. Using MODIS land surface temperature and
normalized difference vegetation index products for monitoring drought in the southern
Great Plains, USA. International Journal of Remote Sensing, 25, 61-72.
Ward, D., Phinn, S. R. & Murray, A. T. 2000. Monitoring growth in rapidly urbanizing
areas using remotely sensed data. The Professional Geographer, 52, 371-386.
Webster, C. 1996. Urban morphological fingerprints. Environment and Planning B:
Planning and design, 23, 279-297.
Weeks, J. R., Hill, A., Stow, D., Getis, A. & Fugate, D. 2007. Can we spot a
neighborhood from the air? Defining neighborhood structure in Accra, Ghana.
GeoJournal, 69, 9-22.
Weier, J. & Herring, D. 2011. Measuring vegetation (NDVI & EVI). NASA online
publication, http://earthobservatory.nasa.gov/Features/MeasuringVegetation.
Weng, Q. 2001. A remote sensing? GIS evaluation of urban expansion and its impact on
surface temperature in the Zhujiang Delta, China. International Journal of Remote
Sensing, 22(10), 1999-2014.
Weng, Q. 2002. Land use change analysis in the Zhujiang Delta of China using satellite
remote sensing, GIS and stochastic modelling. Journal of environmental management,
64(3), 273-284.
228
Weng, Q., LU, D. and Schubring, J. 2004. Estimation of land surface temperature–
vegetation abundance relationship for urban heat island studies. Remote sensing of
Environment, 89, 467-483.
Weng, Q. 2009. Thermal infrared remote sensing for urban climate and environmental
studies: Methods, applications, and trends. ISPRS Journal of Photogrammetry and
Remote Sensing, 64(4), 335-344.
Weng, Q. 2011. Advances in environmental remote sensing: sensors, algorithms, and
applications, CRC Press.
Weng, Q. & Fu, P. 2014. Modeling annual parameters of clear-sky land surface
temperature variations and evaluating the impact of cloud cover using time series of
Landsat TIR data. Remote Sensing of Environment, 140, 267-278.
Weng, Q., Lu, D. & Schubring, J. 2004. Estimation of land surface temperature–
vegetation abundance relationship for urban heat island studies. Remote sensing of
Environment, 89, 467-483.
Wilson, E. H., Hurd, J. D., Civco, D. L., Prisloe, M. P., & Arnold, C. 2003. Development
of a geospatial model to quantify, describe and map urban growth. Remote sensing of
environment, 86(3), 275-285.
Woodward, S. L. 2003. Biomes of Earth: terrestrial, aquatic, and human-dominated.
Wu, C. & Murray, A. T. 2005. A cokriging method for estimating population density in
urban areas. Computers, Environment and Urban Systems, 29, 558-579.
Xian, G. & Crane, M. 2006. An analysis of urban thermal characteristics and associated
land cover in Tampa Bay and Las Vegas using Landsat satellite data. Remote Sensing of
environment, 104, 147-156.
Xiao, J., Shen, Y., Ge, J., Tateishi, R., Tang, C., Liang, Y. & Huang, Z. 2006. Evaluating
urban expansion and land use change in Shijiazhuang, China, by using GIS and remote
sensing. Landscape and urban planning, 75, 69-80.
Xiao, R., Weng, Q., Ouyang, Z., Li, W., Schienke, E. W. & Zhang, Z. 2008. Land surface
temperature variation and major factors in Beijing, China. Photogrammetric Engineering
& Remote Sensing, 74, 451-461.
229
Xu, H. 2007. Extraction of urban built-up land features from Landsat imagery using a
thematicoriented index combination technique. Photogrammetric Engineering & Remote
Sensing, 73, 1381-1391.
Xu, H. 2008. A new index for delineating built‐up land features in satellite imagery.
International Journal of Remote Sensing, 29, 4269-4276.
Xu, H. 2010. Analysis of impervious surface and its impact on urban heat environment
using the normalized difference impervious surface Index (NDISI). Photogrammetric
Engineering & Remote Sensing, 76, 557-565.
Xu, X. & Min, X. 2013. Quantifying spatiotemporal patterns of urban expansion in China
using remote sensing data. Cities, 35, 104-113.
Yang, L., Cao, Y., Zhu, X., Zeng, S., Yang, G., He, J. & Yang, X. 2014. Land surface
temperature retrieval for arid regions based on Landsat-8 TIRS data: a case study in
Shihezi, Northwest China. Journal of Arid Land, 6, 704-716.
Yang, L., Xian, G., Klaver, J. M. & Deal, B. 2003. Urban land-cover change detection
through sub-pixel imperviousness mapping using remotely sensed data. Photogrammetric
Engineering & Remote Sensing, 69, 1003-1010.
Yeon-hee, K. and Jong-Jin, B. 2005. Spatial and temporal structure of the urban heat
island in Seoul. Journal of Applied Meteorology and Climatology, 44(7), 591-605.
Yuan, F. 2008. Land‐cover change and environmental impact analysis in the Greater
Mankato area of Minnesota using remote sensing and GIS modelling. International
Journal of Remote Sensing, 29, 1169-1184.
Yuan, F. & Bauer, M. E. 2007. Comparison of impervious surface area and normalized
difference vegetation index as indicators of surface urban heat island effects in Landsat
imagery. Remote Sensing of Environment, 106, 375-386.
Yue, W., Xu, J. and Xu, L. 2008. Impact of human activities on urban thermal
environment in Shanghai. Acta Geogr Sin, 63(3), 247-256.
Yesserie, A. G. 2009. Spatio-temporal land use/land cover changes analysis and
monitoring in the Valencia Municipality, Spain.
230
Yuan, F., Sawaya, K. E., Loeffelholz, B. C. & Bauer, M. E. 2005. Land cover
classification and change analysis of the Twin Cities (Minnesota) Metropolitan Area by
multitemporal Landsat remote sensing. Remote sensing of Environment, 98, 317-328.
Yuan, F., Wu, C. & Bauer, M. E. 2008. Comparison of spectral analysis techniques for
impervious surface estimation using Landsat imagery. Photogrammetric Engineering &
Remote Sensing, 74, 1045-1055.
Yue, W., Xu, J., & Xu, L. 2008. Impact of human activities on urban thermal
environment in Shanghai. ActaGeogr Sin, 63(3), 247-256.
Yuhai, W. X. B. 1999. Study on the methods of land use dynamic change research [J].
Progress in geography, 18, 1999, 81-87.
Yüksel, A., Akay, A. E. & Gundogan, R. 2008. Using ASTER imagery in land use/cover
classification of eastern Mediterranean landscapes according to CORINE land cover
project. Sensors, 8, 1237-1251.
Zarco-Tejada, P. J., Rueda, C. A., & Ustin, S. L. 2003. Water content estimation in
vegetation with MODIS reflectance data and model inversion methods. Remote sensing of
Environment, 85(1), 109-124.
Zeilhofer, P. & Topanotti, V. P. 2008. GIS and ordination techniques for evaluation of
environmental impacts in informal settlements: A case study from Cuiaba, central Brazil.
Applied Geography, 28, 1-15.
Zemba, A., Adebayo, A. & Musa, A. 2010. Evaluation of The Impact Of Urban
Expansion On Surface Temperature Variations Using Remote Sensing-Gis Approach.
Global Journal of Human-Social Science Research, 10.
Zeng, N. & Neelin, J. D. 2000. The role of vegetation-climate interaction and interannual
variability in shaping the African savanna. Journal of Climate, 13, 2665-2670.
Zha, Y., Gao, J., & Ni, S. 2003. Use of normalized difference built-up index in
automatically mapping urban areas from TM imagery. International Journal of Remote
Sensing, 24(3), 583-594.
Zhang, Q., Pavlic, G., Chen, W., Fraser, R., Leblanc, S. & Cihlar, J. 2005. A semi-
automatic segmentation procedure for feature extraction in remotely sensed imagery.
Computers & Geosciences, 31, 289-296.
231
Zhao, H., & Chen, X. 2005. Use of normalized difference bareness index in quickly
mapping bare areas from TM/ETM+. Paper presented at the Geoscience and Remote
Sensing Symposium, 2005. IGARSS'05. Proceedings. 2005 IEEE International, 3(25–29),
1666−1668.
Zhengming, W. & Dozier, J. 1989. Land-surface temperature measurement from space:
Physical principles and inverse modeling. Geoscience and Remote Sensing, IEEE
Transactions on, 27, 268-278.
Zhong, B. L. 1996. Urban heat island effect of Shenzhen City. Meteorol Mon, 22(5), 23-
24.
Zhou, D., Zhang, L., Hao, L., Sun, G., Liu, Y. and Zhu, C. 2016. Spatiotemporal trends of
urban heat island effect along the urban development intensity gradient in China. Science
of the Total Environment, 544, 617-626.
Zhou, J., Zhan, W., Hu, D. & Zhao, X. 2010. Improvement of mono-window algorithm
for retrieving land surface temperature from HJ-1B satellite data. Chinese Geographical
Science, 20, 123-131.
Zhou, L., Dickinson, R. E., Tian, Y., Fang, J., LI, Q., Kaufmann, R. K., Tucker, C. J. and
Myneni, R. B. 2004. Evidence for a significant urbanization effect on climate in China.
Proceedings of the National Academy of Sciences of the United States of America,
101(26), 9540-9544.
Zhou, W., Huang, G. & Cadenasso, M. L. 2011. Does spatial configuration matter?
Understanding the effects of land cover pattern on land surface temperature in urban
landscapes. Landscape and Urban Planning, 102, 54-63.
Zhu, H. & LI, X. 2003. Discussion on the Index Method of Regional Land Use Change.
Acta geographica sinica, 5, 643-650.
232
APPENDICES
Appendix 01: Mean Annual Recorded Temperature (°C) 1950-2015
Year Urban Station (PBO) Rural Station (APT)
MMxT MMiT MAT MMxT MMiT MAT
1950 30.33 16.53 23.43 - - -
1951 31.83 17.31 24.57 - - -
1952 32.47 17.25 24.86 - - -
1953 32.51 18.08 25.3 31.65 18.5 25.08
1954 31.73 17.55 24.64 30.92 17.68 24.3
1955 30.96 17.25 24.11 30.45 17.3 23.88
1956 30.98 17.58 24.28 30.63 17.6 24.12
1957 29.71 16.88 23.3 29.93 16.94 23.44
1958 31.33 18.03 24.68 31.08 17.75 24.42
1959 30.73 18 24.37 30.23 17.83 24.03
1960 31.64 17.02 24.33 31.38 16.86 24.12
1961 30.2 17.44 23.82 30.04 17.18 23.61
1962 30.46 17.34 23.9 30.23 17.3 23.77
1963 31.19 17.62 24.41 30.97 17.68 24.33
1964 30.35 17.08 23.72 30.18 17.11 23.65
1965 30.84 17.48 24.16 30.56 17.4 23.98
1966 30.98 17.36 24.17 30.72 17.19 23.96
1967 30.28 17.63 23.96 29.74 18.31 24.03
1968 30.31 17.33 23.82 30.24 17.13 23.69
1969 32.18 18.15 25.17 31.27 17.62 24.45
1970 31.34 18.2 24.77 31.3 17.5 24.4
1971 30.96 17.95 24.46 30.91 17.32 24.12
1972 30.78 17.83 24.31 30.71 17.26 23.99
1973 30.62 18.43 24.53 30.43 17.91 24.17
1974 31.15 17.65 24.4 30.56 16.96 23.76
1975 30.37 17.62 24 29.91 16.7 23.31
1976 30.27 18.18 24.23 29.72 17.13 23.43
1977 30.93 18.33 24.63 30.05 17.4 23.73
1978 30.93 18.24 24.59 30.07 17.07 23.57
1979 30.91 17.84 24.38 30.17 16.7 23.44
1980 31.15 17.73 24.44 30.62 17.6 24.11
1981 31.77 17.67 24.72 30.28 17.22 23.75
1982 30 17.17 23.59 29.41 16.79 23.1
1983 29.67 16.98 23.33 29.13 16.5 22.82
1984 31.05 17.99 24.52 30.46 16.69 23.58
1985 31.65 18.28 24.97 30.93 17.63 24.28
1986 30.7 17.67 24.19 29.83 16.73 23.28
1987 31.9 18.42 25.16 30.92 17.68 24.3
1988 31.9 18.86 25.38 30.83 18 24.42
233
1989 31.12 17.73 24.43 30.36 16.86 23.61
1990 30.58 18.44 24.51 30.19 17.87 24.03
1991 30.7 17.73 24.22 30.52 17.48 24
1992 30.69 18.53 24.62 30.39 17.67 24.03
1993 31.59 18.77 25.18 30.79 17.69 24.24
1994 30.91 18.88 24.9 30.51 18.83 24.67
1995 30.53 18.7 24.62 30.07 17.7 23.89
1996 30.44 18.53 24.49 30.09 17.21 23.65
1997 28.6 18.6 23.6 28.28 17.22 22.75
1998 30.63 19.29 24.96 30.42 17.57 24
1999 31.17 19.72 25.45 31.12 18.42 24.77
2000 30.9 19.43 25.17 31.01 18.16 24.59
2001 30.67 19.53 25.1 30.88 18.49 24.69
2002 31.12 20.08 25.6 31.56 18.32 24.94
2003 29.94 19.48 24.71 30.45 17.7 24.08
2004 30.83 20.29 25.56 31.53 17.88 24.71
2005 29.87 19.36 24.62 30.32 16.58 23.45
2006 30.55 20.25 25.4 30.87 17.49 24.18
2007 30.53 19.78 25.16 30.9 16.53 23.72
2008 30.21 19.78 25 30.4 16.74 23.57
2009 31.1 19.97 25.54 31.27 16.9 24.09
2010 30.84 20.1 25.47 31.56 18.64 25.1
2011 29.92 19.49 24.71 30.75 17.98 24.95
2012 30.34 18.44 24.39 30.77 17.28 24.03
2013 30.03 17.94 23.99 30.33 17.21 23.77
2014 29.85 17.91 23.88 29.9 17.06 23.48
2015 30.45 19.76 25.11 31.31 19.58 25.45
Source: Pakistan Metrological Department, Lahore, 2015
Appendix -2: Annual Trends of Ambient Air Quality of Lahore
Annual Average NO NO2 NOx CO SO2 O3 PM2.5
ug/m3 ug/m3 ug/m3 mg/m3 ug/m3 ug/m3 ug/m3
2008 19.92 35.59 55.51 1.23 52.91 47.04 123.28 2009 18.35 37.72 56.06 1.48 67.51 49.49 128.76
2010 20.52 39.25 59.77 2.33 69.25 59.28 135.88
NEQS
(Annual Average) 40 40 5 80 130 25
Source: EPA, Lahore
234
Appendix -3: Air Quality Parameters VS Population density and Temperature
Stop
# Site
Populati
on
Density
Temper
ature OC
Air Quality
CO
(ppm)
SO2
(ppm)
PMs
(μg/m3/hr
NO2
(ppm)
Reference Values (NEQS) 25.8 5 5 25
1 Chauburji 159 35.54 5 20 2.76 0.10
2 Chowk Yaadgar 307 35.94 8 16 2.36 0.08
3 Kalma Chowk 62 35.54 5 20 8.17 -
4 Lahore Hotel Chowk 277 36.33 7 17 7.6 0.17
5 Laskmi Chowk 277 35.94 7 12 1.11 0.2
6 Liberty Market 34 35.54 6 12 2.21 0.15
7 Mochi Gate 274 36.33 5 10 4.53 0.1
8 Muslim Town Chowk 197 35.44 7 15 1.43 0.15
9 Regal Chowk 112 35.94 9 18 1.385 0.2
10 Samanabad Morr 347 36.33 10 20 1.93 0.18
11 Scheme Morr 223 37.11 11 18 2.38 0.22
12 Shadman Chowk 43 35.54 7 18 1.04 0.15
13 Yateem Khana Chowk 335 36.33 9 15 3.61 0.17
Source: Faculty of Environment and Public Health, Institute of Public Health, Lahore;
Lahore Urban Transport Master Plan 2012, Volume II
Appendix -4: Urban Population of Lahore, Punjab and Pakistan
Year Pakistan (%) Punjab (%) Lahore (%)
1951 17.8 3.5 74
1961 22.5 5.4 79
1972 25.4 9.18 82
1981 28.3 13.5 82
1998 32.52 23.02 82.4
2010 36 45.98 82.8
2015 39.2 82.2
Source: GOP, 2015
235
Appendix 5: No. of Registered Vehicles of Lahore
Year No. of Vehicles Year No. of Vehicles
1973 64646 1993 299902
1974 - 1994 339973
1975 - 1995 480167
1976 49453 1996 567186
1977 - 1997 671821
1978 - 1998 638089
1979 85937 1999 702734
1980 - 2000 723381
1981 93725 2001 769644
1982 110998 2002 831033
1983 - 2003 932396
1984 - 2004 1086547
1985 146097 2005 1253101
1986 169785 2006 1464344
1987 - 2007 1703007
1988 - 2008 1944709
1989 - 2009 2129990
1990 249335 2010 2387993
1991 250753 2011 2586460
1992 250753 2012 2687987
Source: Excise and Taxation Department, Lahore Pakistan
Appendix 6: No. of Registered Factories of Lahore
Year No. of Factories Year No. of Factories
1979 937 1998 1536
1980 998 1999 1240
1981 1005 2000 -
1982 1001 2001 1399
1983 994 2002 -
1984 821 2003 -
1985 864 2004 1454
1986 924 2005 -
1987 1016 2006 -
1988 1024 2007 -
1989 1137 2008 1805
1990 1206 2009 1899
1991 1210 2010 1986
1992 1281 2011 -
1993 1310 2012 -
1994 - 2013 2055
1995 1392 2014 2150
1996 1427 2015 2233
1997 1426
Source: Punjab Development Statistics, 2016