erika von schneidemesser, paul monks, john remedios, vijay kanawade

University of Leicester CityZen Contributions

Erika von Schneidemesser, Paul Monks, John Remedios, Vijay Kanawade

Current WorkCompleted London assessmentHC emissions from megacities:

Evaluating VOC emission speciation on the basis of existing ambient VOC observations (Task 3.2) Marylebone Road Data Harwell Data

Developing a customized data analysis package/toolkit (in R) to assess trends in large VOC data sets across multiple years and locations

Greater LondonCity of London and 32 London

boroughs~7.5 million people (2005 )

14 million (entire metro area)1,570 sq km around the Thames RiverMobile sources are a significant factor in London

emissionsOver the past decade decreasing trends of some

atmospheric air pollutants have been observed CO, SO2, NOx, VOCs

In addition to air quality guidelines, London has programs in place to address air pollution from motor vehiclesLow Emissions Zone (2003), Congestion Charging (2008)

VOC results/dataVOC measurements at Harwell and

Marylebone Road in London show VOC emissions have been decreasingExcept some of the lighter alkanes

CO emissions have been similarly decreasingIn agreement with results from US cities, C5-

C8 alkanes, alkenes, ethyne, and aromatics showed similar patterns when normalized to CO, indicating similar emissions sources (transportation)

Task 3.2

Individual VOC Trends

VOC Trends Harwell London

**note y-axes scales

CO Trend

London VOC/CO Ratio Trends

VOC/CO ratios in US Cities

Baker, et al., 2008

London & US cities data

Anthropogenic vs. Biogenic IsopreneLondon Marylebone Road Data

Carbon Monoxide pollution from megacities and urban centres

MOPITT CO Column

EDGARv3.2FT CO

CIESIN Population Density

This shows comparison between the global L2V3 MOPITT CO total column distribution averaged over 7 years, EDGARv3.2FT 2000 anthropogenic emissions for CO, and population density for Asian region.

A very good correlation, especially for China and Indo-Gangetic basin, is observed between MOPITT CO total column and the population density, with the highest Co levels observed where the higher population density occurs.

In China and India, large use of coal as anthropogenic fuels contributes to elevated levels of CO.

Satellite Data

Task 1.2

This plot compares pollution markers such as MOPITT/TERRA surface CO, SCIAMACHY/ENVISAT NO2 total column, MODIS/TERRA AOD and EDGARv3.2FT Anthropogenic CO emissions for China megacities. There is a good agreement between among these pollution indicator suggesting use of satellite data to quantity pollution from urban centres and megacities.[Ratios of MOPITT 850 mb/350 mb give confidence in presence of lower tropospheric CO]

Quantitative Analysis for CO flux

How do we get appropriate background CO concentrations for urban centres, which is largely driven by OH chemistry and uneven source distribution?How do we calculated elevated CO flux over megacity and outflow from urban centres?

Second example of CO pollution from urban centres and comparison with other pollution markers for Japan.

Future WorkAssessment of the scale, magnitude, and

variability of oxidant and particle production in the London metropolitan area (Task 1.4)observations used to assess impact of a megacity

on the regional atm, ozone, and oxidant budgets.Comparison of ‘normal’ conditions to summer

2003 situation (as above) (Task 2.2)role of in-situ chemistry -> SOArole of biogenicsinfluence from forest fires?

Quantification of exports from megacities using satellite data (CO, CO2) (Task 1.2)