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Nicola Stevens, Climate Change Research Group, Council for Scientific and Industrial Research

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Caesar Nkambule, Climate Change Research Group, Council for Scientific and Industrial Research

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S c o p e a n d p u r p o s e o f t h i s h a n d b o o kIn many countries, decision-makers are seeking information from a wide range of disciplines on the potential impacts of climate change on environmental and socio-economic systems.

This handbook is designed to present future climate change scenarios and possible impacts of these changes in an understandable and accessible manner. The handbook is designed to provide a background on the processes of global change and climate change. The handbook will also serve as a basic reference guide to those currently engaged in impacts and adaptation research.

The future climate change projections (estimates of future climate possibilities) presented in this handbook are for the north-eastern region of South Africa only; namely the Mpumalanga, Limpopo and Gauteng provinces. These projections are based on newest information obtained from the latest regionally downscaled climate change models; provided by the Climate System Analysis Group at the University of Cape Town.

It is hoped that readers of this handbook will gain a better understanding of climate change processes, impacts and the possible measures that could be taken to reduce these impacts.

For further information, as well as updated information since the publication of this handbook, please visit www.sarva.org.za/k2c.

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T A B L E O F C O N T E N T S

Part I: Background information on the global and local state of climate change

Climate change and global change – what is it all about? 2

What causes climate change?

The greenhouse effect 3

Observed changes in climate and their effects 4

Future global changes in climate 4

Impacts of climate change on the African continent 5

A brief description of South Africa’s present-day climate 6

Part II: Future scenarios of climate change for north-eastern South Africa

The future climate of South Africa 7

Regional scenarios of climate change over the north-eastern

region of South Africa 8

Changes in temperature

Maximum day temperature 8

Mean day temperature 9

Minimum day temperature 10

Changes in rainfall 11

Changes in evaporation 15

Changes in duration of dry spells 16

Changes in the frequency of rain events 19

Part III: Sector specific impacts of climate change

Impacts of climate change on key sectors

Forestry 22

Agriculture 23

Conservation and tourism 24

Urban and rural development 26

Human health 27

Water resources 28

Part IV: Responding to climate change

How can we respond to changes in climate? 29

Useful resources on climate change 32

2 H O W T O A D A P T E F F E C T I V E L Y T O C L I M A T E C H A N G E

Climate change and global change:WHAT IS IT ALL ABOUT?

The rate of human-induced change is unprecedented. There is now unequivocal evidence that human activities are affecting the Earth’s system at the global scale. Increasingly strong evidence suggests that the functioning of this system is changing in response.

Global change is more than climate change. Global change refers to any changes in the Earth system. The Earth system encompasses the climate system, and many changes in Earth system functioning directly involve changes in climate. The Earth system includes, however other components and processes, bio-physical and human, which are important for its functioning. Some Earth system changes (see Table below), natural or human-driven, can have significant consequences without involving any changes in climate. Global change does not operate in isolation but rather interacts with an array of natural processes and human-driven effects in

complex and multidimensional ways; at local, regional and global scales.

Climate change is “a change of climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods” (United Nations Framework Convention on Climate Change).

Global warming refers only to the overall warming of the planet, based on average increases in temperature over the entire land and ocean surface. It is important to note that climate change is more than simply an increase in global temperatures; it encompasses changes in regional climate characteristics, including temperature, humidity, rainfall, wind, and severe weather events, which have economic and social dimensions.

Changes in the Earth system: Examples of global environmental change (adapted from Steffen et al., 2001)

Component Proximate driver Underlying driver

Land cover Clearing of land (cutting and/or burning), agricultural practices (tillage, fertilisation, irrigation, pest control, high-yielding crops, and erosion), and abandonment.

Demand for food (bio-fuels), recreation, migration (refugees), property rights, incentives, market growth.

Atmosphere Fossil fuel burning, land-use change (rural area to large-scale agricultural practices), biomass burning, indus-trial technology.

Demand for mobility, consumer products, subsidies, technological changes in transport.

Biodiversity Clearing of forest/natural ecosystems, introduction of alien species.

Demand for food, urbanisation, changes in policy.

Water Dams, impoundments, reticulation systems, waste disposal tech-niques, management practices.

Demand for water (direct human use), food (irrigation), consumer products (water usage in industrial processes).

Coastal/marine Land-cover conversion, groundwater removal, fishing intensity and technique, coastal building patterns, sewage treatment technology, urbanisation.

Demand for recreation, lifestyle, food, employment.

Social triggersRapid economic or political

shifts, War

Predisposing environmental conditionsClimatic variability, Soil characteristics,

Fire frequency, Natural disasters

Climate refers to the aggregation of all components of weather – precipitation, temperature, and

cloudiness.

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The Earth’s climate system is driven by the energy that is continuously received from the sun. The bulk of this energy is in the short-wavelength part of the electromagnetic spectrum.

About 30% of the incoming solar energy is reflected back to space by clouds and the Earth’s surface before it can warm the planet. About 70% of the incoming energy is absorbed by the oceans, continents and the atmosphere. The absorbed heat is later re-emitted in the form of infrared radiation, or transferred by sensible and latent heat fluxes.

Certain gases in the troposphere and stratosphere absorb most of the outgoing infrared radiation, however before it can escape to space, thereby warming the atmosphere before the heat is once again re-emitted. These are referred to as greenhouse gases (GHG). Without the presence of these gases in the atmosphere, the average temperature at the surface of present-day Earth would be about -18°C. The warming effect of the greenhouse gases, called the ‘greenhouse effect’ or ‘natural greenhouse effect’, results , however in the average surface temperature being about +14°C. Without the greenhouse effect, life on Earth would be markedly different to that with which we are familiar. The two gases, carbon dioxide and water vapour, are primarily responsible for a large portion of the greenhouse effect.

Anthropogenic (or human-driven) emissions of green-house gases, resulting from the burning of fossil fuels and deforestation, have increased the atmosphere’s ability to absorb the Earth’s outgoing infrared radiation. This is referred to as the ‘enhanced greenhouse effect’. The consequences of this effect can be clearly seen in the worldwide trend of rising temperatures, that is, in the

form of global warming. These increased atmospheric temperatures have knock-on effects for atmospheric moisture availability (rainfall), sea surface temperatures, ice sheets and glaciers.

Global GHG (water vapour (H20), carbon dioxide (C02), nitrous oxide (N20) and methane (CH2) emissions due to human activities have grown since pre-industrial times, with an increase of 70% between 1970 and 2004 (IPCC, Fourth Assessment Report, 2007). This increase has come from energy supply, transport and industry as well as emissions from residential and commercial buildings, deforestation, and agricultural sectors.

Since the industrial revolution in the 18th century human society has been producing greenhouse gases in ever-increasing amounts. As a result, the concentrations of greenhouse gases in the atmosphere are now higher than at any time in the past 650 000 years. Source: IPCC, Third Assessment Report, 2001.

W h a t c a u s e s c l i m a t e c h a n g e ?

T H E G R E E N H O U S E E F F E C T

And he huffed and he puffed but this problem would

not go away.

H O W T O A D A P T E F F E C T I V E L Y T O C L I M A T E C H A N G E4

O b s e r v e d c h a n g e s i n c l i m a t e … a n d t h e i r e f f e c t sAnthropogenic (human-induced) climate change is already occurring and many natural systems are being affected.

Warming of the climate system is evident from observations of increases in global average air and ocean temperatures, widespread melting of snow ice and rising average sea level (IPCC, 2007 Synthesis Report, Fourth Assessment Report).

Since 1906 temperatures have increased by 0.74°C. Eleven of the last twelve years (1995-2006) rank among the twelve warmest years on record since 1850. Some of the observed effects of warming can be described as follows:

• Heatwaveshavebecomemorefrequent• Colddays,coldnightsandfrostshavebecomeless frequent• Earlier timing of spring events, such as flowering, bird migration, and egg-laying as well as poleward shifts in animal and plant ranges• Changesinalgal,planktonandfishpopulationsizes and distributions

The global average sea level has risen at an average rate of about 1.8 mm per year over 1961 to 2003 and at an average rate of about 3.1 mm per year from 1993 to 2003. This has caused the loss of wetlands and mangroves in many areas (for more information on sea-level rise experienced in South Africa, see South Africa’s Second National Communication on Climate Change).

Satellite data show that the average extent of the Arctic sea ice has shrunk by 2.77% per decade with larger

increases during summer of 7.4% per decade. Mountain glaciers and snow cover have decreased in the northern and southern hemispheres.

Trends from 1900 to 2005 show that rainfall has increased in the eastern parts of North and South America, Northern Europe and northern and central Asia and has decreased in the Sahel, the Mediterranean, south-western Africa and parts of southern Asia. This has affected runoff and earlier spring peak discharge in many glacier and snow fed rivers. An increased frequency of high rainfall events has also been observed.

Future global changes in climateDespite international concern about climate change, greenhouse-gas concentrations in the Earth’s atmos-phere are set to increase at an accelerated rate if current trends in emission rates persist.

Temperatures are expected to increase by between 1.8°C and 4.0°C (see figure below).

The global average sea level has risen at an average rate of about 1.8 mm per year over 1961 to 2003...

Source: United Nations Environmental Programme

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Africa is one of the most vulnerable continents to climate variability and change because of multiple stresses and low adaptive capacity. The livelihoods of people in Africa, including South Africa, are often directly linked to the climate of the area.

By 2020: • A large proportion of Africa’s population is projected to be exposed to increased water stress due to climate change induced shifts in water availability coupled with increased water demand. • Yields from rain-fed agriculture could be substantially reduced in certain areas, which would further adversely affect food security and exacerbate malnutrition.

I m p a c t s o n A f r i c a

S o u t h e r n A f r i c a• Heightenedwaterstress• Possiblesouthwardexpansionofthetransmissionzoneofmalaria• Climatechangesmayincertainareasfavourhorticultureover plantation forestry• FynbosandSucculentKarooarelikelytobethemostvulnerable ecosystems whilst the savanna is argued to be more resilient• Coastalmarinefisheriesarelikelytobenegativelyaffectedby changes in the Benguela current

N o r t h A f r i c a• Shiftsindesertdunes• Climatechangecouldnegatively impact mixed rain-fed and semi-arid agricultural systems, particulary the length of the growing season, for example on the margins of the Sahel• Possibledecreasesinrunoffinparts of North Africa by 2050• TheNileriverissensitivetorisesin sea-level, as salination could occur

W e s t a n d C e n t r a l A f r i c a• Negativeimpactoncropproductionandpossible agricultural GDP.• PopulationsofWestAfrica,includingthelargecities of Lagos and Banjul, living in coastal settlements could be affected by the projected rise in sea level• Changesinthecoastalenvironment,suchasthe removal of mangroves and coastal degradation, could have negative impacts on fisheries and tourism as well as on the resilience of those settlements to heavy storms• Changesinecosystemrangesandspecieslocations as well as possible increased risk of species extinction. The rate and magnitude of deforestation in Central Africa could exacerbate these losses in biodiversity

W e s t e r n I n d i a n O c e a n I s l a n d sGreatest risk of flooding due to changes in rainfall, intense storms and sea level rise. Coral reefs are projected to be further degraded

E a s t A f r i c a• ChangesinthestorageoftheEastAfricanGreatLakes and reservoirs due to changes in rainfall, which could adversely impact agricultural production• Previouslymalaria-freeareasinEthiopia,Kenya,Rwanda and Burundi could experience modest changes to stable malaria by the 2050s, with conditions for transmission becoming suitable by the 2080s• Ecosystemimpacts,includingimpactsonmountain biodiversity• DeclinesinfisheriesinsomeofthemajorEastAfrican lakes could occur due to increases in temperature coupled with overfishing• Drought


South Africa has a warm climate, and much of the country experiences average annual temperatures of above 17°C. The southern and eastern escarpments are the regions with the lowest temperatures, due to the decrease in temperature with altitude. The warmest areas are the coastal areas of KwaZulu-Natal, the Lowveld of KwaZulu-Natal and Mpumalanga, the Limpopo valley and the interior of the Northern Cape.

The oceans surrounding South Africa have a moderating influence on the temperatures experienced along the coastal areas. The warm Agulhas current causes the east coast to be significantly warmer than the west coast, where the cold Benguela current and upwelling induce lower temperatures.

Regional topography and proximity to the oceans also influence the climate. The western, southern and eastern escarpments lead to a high plateau of about 1 250m above sea-level. The plateau experiences hot summers and cold winters, but the oceans moderate the climate of the coastal plains, providing milder winters. The warm Agulhas current causes the eastern coastal areas to have a warm and humid climate, whilst the cold Benguela current along the west coast contributes to the arid climate of this region.

Rainfall over South Africa is highly variable in space, and a west-east gradient in rainfall totals is evident. The west coast and western interior are arid to semi-arid areas. The air above the cold Benguela current and upwelling region along the west coast is relatively dry and cold, contributing to the dry climate of the west coast and adjacent interior. Rainfall totals are high over and to the east of the eastern escarpment of South Africa due to orographic precipitation. Rainfall patterns over the country display well-pronounced intra-annual and inter-annual variability mainly due to the El Niño Southern Oscillation (ENSO)1.

The different types of weather experienced over South Africa in combination cause the country to consist of vastly different climatological regions, with most regions also displaying large inter-annual variability in their climate. The variability of weather and climate over South Africa poses challenges for weather prediction, seasonal forecasting and the projection of climate change over the country.

SEASONAL CLIMATE CHARACTERISTICS

Summer(December-January-

February)

Autumn(March-April-May)

Winter(June-July-August)

Spring(September-October-

November)

This is the most important rainfall season for the central and northern interior of South Africa.

Heat-induced thunderstorms frequent the South African interior, being most abundant over the eastern escarpment and Highveld areas.

Rainfall decreases rapidly over the eastern interior of South Africa during this time.

This is, however, an important rainfall season for the western interior of South Africa (espe-cially the Northern Cape and Eastern Cape interiors).

The Cape interior regions receive significant amounts of rainfall during autumn from cloud bands that oc-cur to the west of the most well-pronounced regions of subsidence.

Weather is characterised by sunny days, clear skies and cold nights.

Frost is common especially over the higher altitude parts of South Africa.

Cold front systems bring rain to the south-western Cape and the Cape south coast. On occasion this cold front intrudes northwards and brings “cold snaps”, and in extreme cases causes snowfall to occur over the Free State and the Highveld regions of Gauteng and Mpumalanga.

Spring is characterised by the onset of rainfall over the interior regions of South Africa, with the first of the significant falls of rain typically occurring overKwaZulu-Natalbeforespreading deeper into the interior.

A weather system that may bring snow and heavy falls of rain to the South African interior during spring, is the cut-off low. These weather systems may occur at any time of the year, but are most common during spring and autumn.

1El Niño refers to the large-scale phenomenon associated with a strong warming in sea-surface temperatures across the central and east-central equatorial Pacific Ocean. An El Niño event occurs every three to seven years. La Niña, on the other hand, refers to the periodic cooling of sea-surface temperatures in the central and east-central equatorial Pacific Ocean.

South Africa is a country that experiences

an astounding variety of different weather conditions. Climate

refers to the long-term average of weather

conditions.

A b r i e f d e s c r i p t i o n o f S o u t h A f r i c a ’ s p r e s e n t - d a y c l i m a t e

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Global circulation models (GCMs) have become the primary tools for the projection of climate change. These mathematical models, based on the laws of physics, are used to estimate the three-dimensional changes in the structure of the atmosphere that may take place in response to enhanced anthropogenic forcing. Projections of future climate change by GCMs may provide insight into potential broad-scale changes in the atmosphere and ocean, such as shifts in the major circulationzonesandthemagnitudeofsea-levelrise.

The term projection refers to estimates of future climate possibilities.

However, because these models are computationally expensive, they can only be integrated at relatively coarse horizontal resolutions –namely at typical grid spacings of about 2° - 3° in both longitude and latitude. At these resolutions, the regional details of climate

(such as the characteristics of orographic precipitation and

thunderstorms) and climate change cannot be sufficiently described.

Additional uncertainties surrounding climate projections include the role of natural variability, the

future rate of increase of greenhouse gas concentrations and the systematic simulation errors associated with each individual GCM. To improve the detail of the GCM projections, the methods of statistical and dynamical downscaling are used to obtain high-resolution projections of climate change over areas of interest.

Such downscaled scenarios of climate change over the north-eastern region of South Africa are described in this section. The current climate variable is compared with the average future (projected) conditions — first spatially and then graphically over a monthly time series. Seasonal changes in precipitation variables (total rainfall, the duration of dry spells, and the frequency of rain days) are presented spatially and a graph showing the envelope of change1 is presented in order to demonstrate the range of future possibilities.

Future temperature was obtained from two dynamic regional climate models (PRECIS and MM5) and future precipitation variables were obtained from ten statistically downscaled GCMs (IPSL_CM4, GFDL_CM2_0, CCMA_CGCM3_1, MRI_CGCM2_3_2A, CSIR0_MK3_0, CSIR0_MK3_5, MPI_ECHAM5, GISS_MODEL_E_R, CNRM_CM3, MIUB_ECHO_G), made available by the Climate System Analysis Group at the University of Cape Town.

1An envelope of models is used to project different (but equally plausible) climate futures

The future climate of South AfricaSouth Africa’s Second National Communication describes the likelihood of increased temperature as being greater towards the interior, and less in coastal areas. Assuming a moderate to high growth in greenhouse gas concentrations by mid century, the coast is likely to warm around 1°C and the interior around 3°C. By 2100, under the same set of assumptions around greenhouse gas emissions, the temperature increase is likely to approach 3°C on the coast, and 5°C in the northern interior. By mid century, projected increased temperatures appear similar for all assumptions around South Africa’s future greenhouse gas emissions.

There are significant geographical differences to future projected rainfall changes. Drier conditions are predicted for the south west of the country in both seasons. Rainfall intensity is likely to increase, but to not necessarily imply an increase in total rainfall, with important implications for impacts (see sections to follow). Greater evaporation rates are likely to increase drought incidence and intensity (as defined by the response of available soil moisture and available free water), possibly even in regions where total rainfall increases.

Regional scenarios of climate change over the north-eastern region of South Africa


CLIMATE CHANGE PROJECTIONS

1. Maximum temperatureIncrease in annual maximum day temperature of approximately 0.5°C. A decrease of between 0.27°C and 1.26°C is possible for April, May, June, and July.

C h a n g e s i n Te m p e r a t u r e

Present Conditions Future Conditions

Max

imum

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2. Mean temperature Increase in annual mean day temperature of between 0°C and 0.89°C. Spring (September-October-November) shows the greatest change in mean day temperature, with an average increase of 1.28°C expected over the three months.

Spring (September-

October-November) shows the

greatest change in mean day

temperature...


Present Conditions

Future Conditions


C h a n g e s i n Te m p e r a t u r e3. Minimum temperature Increase of between 0.6°C and 1.16°C in the minimum day temperature for all months of the year, with no regions experiencing below zero temperatures.


Min

imum

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4. Total Annual Rainfall An increase in total annual rainfall is expected for the whole region, with possible distinct increases along the escarpment.

C h a n g e s i n Ra i n f a l l


Present Conditions

Maximum Future Rainfall

Future Conditions

Minimum Future Rainfall


C h a n g e s i n Ra i n f a l l5. Total Monthly RainfallFuture annual rainfall is expected to range from 301 mm to 758 mm per annum. The majority of this rainfall is expected to fall during the summer months (December-January-February).

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6. Seasonal Change in RainfallAn extension of the rain season may occur into early spring due to the increase in rainfall predicted for September-October-November. Autumn and winter are also expected to receive more rainfall and this may have significant consequences for biological triggers and cropping calendars.


Summer Autumn

Winter Spring


C h a n g e s i n Ra i n f a l l7. Envelope of Rainfall ChangeRainfall is expected to increase by between 85 and 303 mm per year for the region as a whole. The greatest increase in rainfall is expected during February, April and September with increases of above 30 mm according to the upper limit of change predicted from the downscaled models. There are however, a range of possibilities where rainfall could decrease during some months (refer to the lower limit of change).

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8. Evaporation Despite the increase in mean annual rainfall, future evaporation is expected to increase. This means that there less likely be less water available for use in the future.

Despite the increase in

mean annual rainfall, future

evaporation is expected to increase.


Present Conditions

Future Evaporation


D r y - s p e l l D u r a t i o n9. Annual Dry-spell DurationThe numbers of dry days per year are expected to decrease due to the future increase in mean annual rainfall.


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10. Envelope of change in the number of dry daysThe greatest change in the number of dry days is projected for June whereas there is little change expected for the summer and spring months (September - January).


D r y - s p e l l D u r a t i o n11. Seasonal change in Dry-spell durationThere is little to no change in the dry-spell duration in spring and summer. For the region in general, the dry-spell duration is expected to decrease in autumn by between half a day and 3 days and in winter by between 1 and 6.7 days. This corresponds with the increase in rainfall expected during these seasons.

Summer Autumn

Winter Spring

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12. Annual frequency of rainfall events The number of rain events is expected to increase. This could infer that the chances of floods may increase.


Frequency of Rainfal l Events


13. Monthly frequency of rainfall eventsThe majority of rain events are expected to occur in November, December and January, which have the highest number of days experiencing rainfall.


Frequency of Rainfal l Events

14. Envelope of change in number of rain daysThe number of rain days per month is expected to increase by between 1.036 and 2.188 days. This small change in the number of rain days per month compared with the increase in rainfall demonstrates that the intensity of rain events and possibly the severity of rain events may increase. The lower limit of change shows a decrease in the number of rain days for the majority of the year; this may also be a likely possibility.

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15. Seasonal change in number of rain daysIn some areas the numbers of days experiencing rain are the same or lower than current numbers despite the projected increase in rainfall for those areas, inferring an increase in the intensity of rain events.


Summer Autumn

Winter Spring


F O R E S T R YSouth Africa’s forestry sector is sensitive to climate change as it is based on the plantation of non-indigenous species (species that are not typical of South Africa). Land availability, water demand as well as environmental and socio-economic conditions affect the vulnerability of the sector to climate change.

Commercial forestry plantations occupy approximately 1.1% of South Africa, with Mpumalanga housing one of the largest forestry plantation areas. The three major species grown in commercial plantations are pines, eucalypts and wattle.

Given the projected increases in temperature and changes in rainfall, certain areas may not be climatically suitable for the production of a specific species (as different species have different climatic constraints, such as mean rainfall and mean temperature) and some areas may no longer be suitable for commercial forestry. However, areas that are at present not climatically suitable for forestry may become suitable in the future.

Tree breeding can produce trees that match future projected site conditions (in regions where future

site conditions are predictable). Alternative forms of silviculture, such as mixed species forests, agroforestry, and the use of adapted indigenous tree species could yield more resilient forests in areas where site development uncertainty is high or water use restrictions prohibit the use of fast-growing plantation species.

Climate change is likely to exacerbate existing declines in river runoff due to water use by commercial plantations, agriculture, woody exotic invasive species, and urban and industrial land use. Consequently, an integrated ecosystem management approach, or ‘multiple benefits’ approach must be considered. Such an approach should be able to provide an optimal portfolio of land-use forms in an area which could integrate production, environmental, climate change adaptive, sequestration and mitigation objectives and socio-economic aspects for sustainable landscape management.

Given the lengthy rotation of commercially grown forest species (7 – 30 years), it is crucial that decisions on the most effective climate change adaptation strategies are developed and implemented in a timely manner.

S e c t o r s p e c i f i c i m p a c t s o f c l i m a t e c h a n g e

This section outlines specific information about the nature of future impacts across a range of sectors, namely forestry

agriculture, conservation and tourism, health, water resources, and rural development and urban planning.

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Projected increasing temperatures and changes in rainfall timing, amount and frequency, have critical implications for the full range of agricultural systems in South Africa. Agricultural production is generally responsive to current climate variability. Degradation of South Africa’s natural agricultural capital may be exacerbated by climate change (as well as existing challenges to the agricultural sector). Emerging agriculture is likely to be particularly adversely affected, due to, in many cases, lower adaptive capacity.

The agricultural sector is likely to feel the direct and indirect impacts of projected climatic changes in a number of ways: • Crop productivity may decrease for even small increases in temperature, (despite benefits obtained through increased photosynthetic activity as a result of increased carbon dioxide).• Predicted higher temperatures may negatively impact organic matter; in an environment where soil organic matter retention is already affected by other stressors such as grazing, addition of fertiliser and manure, burning, and soil cultivation. • Increased temperatures and resulting evaporation are likely to increase irrigation demands, in a country

where existing water supply and quality difficulties already provide stress to the irrigated agriculture sector. • Existingwatersupplyandwaterqualitychallenges already stress irrigated agriculture. Predicted climate change impacts on water supply and quality will critically complicate these existing stresses, increasing existing water competition.• Increasinglyexceedingthetemperaturethresholds abovethethermalcomfortzoneoflivestock,which could induce behavioural and metabolic changes including altering growth rate, reproduction and ultimately mortality.• Conversely, increases in temperature during the winter months could reduce the cold stress experienced by livestock, and warmer weather could reduce the energy requirements of feeding and the housing of animals in heated facilities. • Higher temperatures may favour the spread of significant pests and pathogens to a range of agricultural systems. For example, a number of pathogens of concern to the highly valuable vegetable and fruit industries prefer higher temperatures.

Summary of the possible impacts of climate change on livestock production systems

Socio-economic/livelihood impacts • Changesinincomesderivedfrom livestock production• Shiftsinlanduse(including consequences of land reform)• Overallchangesinfoodproduction and security

Indirect livestock impacts through ecological impacts • Increasedfrequencyofdisturbances, such as wild fires• Changesinbiodiversityandvegetation structure• Changesinsoilnutrients

Direct livestock impacts • Changesinforagequalityandquantity• Changesinthelengthofthegrowingseason• Changesinwaterqualityandquantity• Reductioninlivestockproductivity• Behaviouralandmetabolicchanges• Increasedprevalenceof‘newanimaldiseases’

A G R I C U L T U R E


South Africa is world-renowned for exceptionally high levels of biodiversity. Among areas of comparable size - 2% of the world’s land area - Southern Africa has the richest flora in the world, being home to 10% of all known plant species and 7% of all reptiles, birds, and mammals.

Conservation agencies, particularly state-run conservation areas have a mandate to maintain biodiversity, and through several Acts are obliged to meet a range of biodiversity targets. It is in this sector that the heaviest impacts may lie, as the projected changes carry a heavy responsibility of conserving the country’s biodiversity in spite of such impacts. The implications are far-reaching as changes in plant and

animal ranges and biome shifts, as well as the alteration of ecosystem functioning, mean that these organisations have the duty to use the climate change predictions and plan ahead so as to continue to meet their biodiversity conservation responsibility. The organisations need to ensure that areas of future biodiversity hotspots are incorporated as conservation areas at this stage to ensure their continued conservation. This involves expanding or changing the configuration of protected areas, often at great expense ; and/or working with land owners to conserve biodiversity outside formal protected areas.

Several other activities in this sector run as commercial or semi-commercial concerns, the most common being hunting and eco-tourism. These sectors will be affected by changes in the biodiversity of the area and will also be impacted by factors that will negatively impact the tourist experience, such as increased bush encroachment, altered animal and plant assemblages and an increase in discomfort levels caused by increased temperatures. Management actions certainly will be able to mitigate against certain of these impacts, but such mitigation actions will no doubt result in an increased cost to this sector.

C o n s e r v a t i o n a n d To u r i s m

25

Impacts on ecosystems and biodiversity:

• Globally, 20-30% of species assessed to datemay become extinct as temperatures increase.• In South Africa, several studies indicate that the majority of endemic species are likely to show contractions of geographic range, and that up to 30% of endemic species may be at increasingly high risk of extinction. One specific study shows a significant range contraction in almost 80% of the 179 species (including 34 bird, 19 mammal, 50 reptile, 15 butterfly and 57 other invertebrate species) included in the research. The majority of these range contractions are expected to occur in the eastern half of South Africa.• Rising atmospheric CO2 levels may be increasing the cover of shrubs and trees in Grassland and Savanna biomes, with mixed effects on biodiversity, and possible positive implications for carbon sequestration. For example, Colophospermum mopane woodlands are known to have a low density of herbivores due to the low grass biomass and the high density of the trees, which increases ungulates’ susceptibility to predation. An expansion of C. mopane will have strong negative impacts on the tourism experience through potentially reduced numbers of game within these patches, resulting in reduced game viewing opportunities. • Changes in the timing of plant and animal life cycles will impact conservation areas as this may in future change the species assemblages of these areas. Due to the changing climate a disconnect may occur between the timing of behaviour and the available resources on which the behaviour depends. The individual impacts of these changes will likely scale up to have several ecosystem responses, including the range and distribution shifts of species and communities, the composition of and interactions within communities, and the structure and dynamics of ecosystems.

• Additional stresses tobiodiversity thatwill interact with climate change include wildfire frequency (which has already shown climate change-related increases in the Western Cape region) and alien invasive species, which are likely to be advantaged by changed climates and increased atmospheric carbon dioxide concentrations.• Thecombinedeffectsoftheseandstressesrelating to land use and fragmentation of habitats will further increase the vulnerability of biodiversity to climate change. • The ability of ecosystems to adapt naturally to new conditions may be exceeded in the late century due to a combination of climate change, fires, floods and droughts as well as other global change drivers such as land-cover change and pollution.

Source: Climate Change, CSIR, 2010


As a consequence of the South Africa’s unique history, the former Bantustan areas are generally characterised by densely populated and highly dispersed

settle-ments with high concentrations of poverty and limited access to employment,

livelihoods and socio-economic services. Such inequalities increase people’s vulnerability to the physical impacts of climate change. For example, the risk of water-borne diseases due to changes in rainfall patterns and temperature increases expected with climate change will be increased in households without proper access to potable water.

The resources spent in the community to deal with patients affected by water-borne diseases, for example, may divert funding away from capital investments necessary for economic development. In addition, these communities are dependent on a range of natural resources for firewood, wild fruits and herbs, medicines and craft materials, which contribute to their livelihoods. These resources are already under increasing pressure and future use combined with changes in production as a result of climate change may lead to unsustainable levels of harvesting.

People who reside in informal settlements have been identified as one of the most vulnerable populations globally. Informal settlements are often vulnerable to water-related disasters such as floods and severe storms, particularly in cases where the communities are located on flood plains and there is an absence of proper water infrastructure.

Key questions for local municipalities are:• What impact will climate change have on the capacity of municipalities to deliver the services and utilities that the communities they serve need and expect?• What are the current and potential impacts of climate change on informal settlements located in the local and district municipalities?• Are municipal plans for economic development viable in light of the projected changes in climate?• What effect will extreme events such as droughts and floods have on the life cycle of infrastructure where design is currently based on historical observations?• Whataretheconsequencesofclimatechangefor the segment of the population currently living below RDP standards?

Planning decisions on the local and district levels are supported by Integrated Development Plans (IDP) which serve as a framework that informs decisions related to development in a specific area. The concentration of activities in one sector limits flexibility to switch to other sectors that are less sensitive to changes in climate, such as manufacturing and services. It is significant that agriculture has been identified as the sector through which a number of the local municipalities in Mpumalanga and Limpopo decided to focus future economic development. The predicted changes in climate, however, could force the shutdown or relocation of agricultural business in vulnerable areas, which would have an enormous effect on economic development of the area as well as on a community which is made up largely of unskilled labour.

U r b a n p l a n n i n g a n d r u r a l d e v e l o p m e n t

“Climate change is a serious threat to

development”

The impact of climate change on specific sector activities reflects on the economic

sustainability of the municipality

COMMERCE

AGRICULTURE

MINING

TOURISM

MANUFACTUR-ING

FORESTRY

LOCAL ECONOMIC

DEVELOPMENT

27

Direct and indirect health effects of climate change

The health of humans is closely linked with their surrounding environment. Climate change is expected to affect the fundamental requirements for a healthy society: clean air, safe drinking water, sufficient food resources and secure shelter.

Documented direct health effects of climate change include extreme events such as floods, droughts and thermal stress (such as strokes, rashes and dehydration). Indirect health effects of climate change include the spread and/or increase of the incidence of infectious and vector-borne diseases, water-borne pathogens, water quality, air quality, and food availability and quality. Increasing temperatures may favour the geographical expansion of the borders of malaria and cholera. This is supported by several predictive models, as well as surveillance and direct observations in many quarters.

The actual health impacts that will occur in the future are strongly dependent on local environmental conditions, the socio-economic status of the area, and the range of adaptation measures put in place to reduce the threats. Another important factor that may increase the threat to human health is population displacements due to extreme weather events and sea-level rise (affected

populations are termed climate change refugees) as well as climate-related conflicts.

The vulnerability and capacity of a community or communities to adapt to health threats depend on their general health status, for example the prevalence of cardiovascular diseases, HIV/Aids and TB, chronic non-communicable diseases, malnutrition or stunting especially in young children; level of education and awareness; economic status; general demographic profile (for example gender and age profiles); migration patterns and levels, level of infrastructure development and maintenance; access to and availability of skilled medical personnel and facilities, and population density.

One major difficulty in quantifying the impacts of climate change on human health is the lack of long-term health data for a specific area or areas that can be linked to changes in the climate system. The links between human health, the natural environment and systems operating at different time and spatial scales contribute to the complexity associated with distinguishing the health effects of climate change from other global environmental changes. In addition, climate change is one of several factors that can affect human health.

Human HEALTH

Regional climate changes•Increasedtemperatures•Changesinrainfallregimes•Heatwaves•Extremeweatherevents

Source: Redrawn from World Health Organization, Online at: WHO Climate Influences

Contamination paths

Transmission dynamics

Changes in agro-ecosystems and hydrology

Socioeconomic and demographic disruption

Modulating influences

Direct health effects•Temperature-relatedillnessanddeath•Extremeweather-relatedhealtheffects

Indirect health effects•Airqualityandpollution•Changesindistributionandpotencyof allergens and mycotoxins•Water-andfood-bornediseases•Vector-androdent-bornediseases•Effectsoffoodandwatershortages•Mental,nutritional,infectiousdiseases

The incidence of

malaria could increase with the expansion of

habitats suitable for mosquitoes that transmit

malaria


The close interconnectedness between climate and the hydrological cycle means that water resources will be impacted by climate change. This will place increased pressure on water resources, ultimately threatening the sustainability of future availability.

Currently, 98% of South Africa’s surface water yield, as well as 41% of the annual usable potential of groundwater have been allocated to use.

Water resources are directly impacted by current climate variability and it is expected that climate change could impact resources significantly in the future. It is estimated that an 8% reduction in rainfall results in a 31% reduction in groundwater recharge and a 30% reduction in surface runoff. In addition, climate change is expected to exacerbate the poor state of major rivers in South Africa.

The major risks to water resources include:• decreasedavailability ofwater in rivers as a result of net effect of increased temperatures and increased evaporation, coupled with shifts in the timing and amounts of rainfall;• changesintheconcentrationandtimingofhighand low flows due to changes in rainfall;• increased incidence of floods as the incidence of very heavy rain events increases; and• increased risk of water pollution and decreased water quality linked to erosion and high rainfall events, which increase the presence of sediments, nutrients, dissolved organic carbon, pathogens and pesticides, and increased water temperature, which promotes algal blooms.

The impacts of climate change on water resources are likely to be exacerbated by changes in land-use and poor land-use management.

The political and practical imperative to improve access to water for both rural and urban poor will create further stress on the hydrological system as a result of the increased human demand.

Despite the influence of climate change, it is predicted that by 2025 South Africa will be using up the majority of its surface water resources. This is as the sustainability of water resources and ultimately the availability of water in the future will depend on both supply and demand pressures. Supply pressures include climate change and environmental degradation, where for example pollution reduces the amount of clean water available for use. Demand pressures include population growth and density which lead to increased demand for domestic, industrial and agricultural water use, as well as knock-on effects of the management of water usage.

WAT E R R E S O U R C E S

The majority of catchments in South Africa use more water than is available on an annual basis.

Currently, 98% of South

Africa’s surface water yield, as well

as 41% of the annual usable potential of groundwater

are allocated to use.

29

Adaptation refers to the “adjustments in natural or human systems in response to actual or expected climatic stimuli or their effects, which moderates harm or exploits beneficial opportunities” (IPCC 2007).

There are two main types of adaptation:• Anticipatory Adaptation is adaptation that takes place before impacts of climate change are observed. Also referred to as proactive adaptation. • Reactive Adaptation is adaptation that takes place after impacts of climate change have been observed.

Climate change adaptation is a means of responding to the impacts of climate change. It aims to moderate the impacts as well as to take advantage of new opportunities or to cope with the consequences of new conditions. The capacity to adapt is dependent on a region’s socio-economic and environmental situation as well as the availability of information and technology.

Mitigation refers to the measures taken to reduce the emission of greenhouse gases and to enhance sinks of greenhouse gases, such as aforestation measures.

Vulnerability refers to the “degree to which a system is susceptible to, or unable to cope with, adverse effects of climate change, including climate variability and extremes. Vulnerability is a function of the character, magnitude, and rate of climate variation to which a system is exposed, its sensitivity, and its adaptive capacity” (IPCC 2007).

Climate change will not be felt in isolation of other stressors. In many sectors, adaptive strategies appear to be under way, although most are centred on coping with short-term risk. Few clear strategies, at present, consider long-term adaptive planning. Adaptive possibilities are considered per selected sector in the table below.

Adaptation strategies that are effective and/or suitable across sectors need to be prioritised; this is termed a Multi-Sectoral Approach. This would involve simultaneously addressing a range of objectives, which include climate change adaptation, carbon sequestration, mitigation of greenhouse gas emissions, biodiversity conservation and sustainable livelihoods. Many existing strategies and policies may be merely supported or amended to improve resilience in the face of climate change implications for key sectors.

Several new adaptation options are emerging. Various institutions are emerging as key for enhanced facilitation of adaptation to climate variability and climate change. Such institutions include those disaster risk reduction and early warning oriented institutions prompted by the Disaster Management Act. Further attention and support needs to be provided for the role of effective planning and climate change particularly at local levels (e.g. municipalities). Lastly, critical priority areas include finding ways to expand the business sector’s engagement in adaptation as well as mitigation and improving understanding of the role of behaviour change and climate change adaptation.

Source: IPCC, Fourth Assessment

Re s p o n s e s t o t h e i m p a c t s o f c l i m a t e c h a n g e


S e c t o r A d a p t a t i o n o p t i o n sAgriculture •Shiftsincropcalendarsandtheswitchingofcrops.

•Soil,waterandnutrientconservationpractices.•Improvedlandmanagement,suchaserosioncontrol.Switchtomoreresilient livestock production systems.•Switchtomoreresilientlivestockproductionsystems.

It is important to note that climate change impacts may make agriculture increasingly unfeasible as a livelihood strategy for the rural poor. This must be taken into account in developing policy and strategy for the emerging agricul-ture sector.

Forestry •Firefrequencyandintensityislikelytoincreaseduetotheincreaseindry spells and temperature. The commercial forestry industry may respond through the combination of pro-active fuel reduction and re-active fire fighting, but this will certainly increase production costs. •Themitigationpotentialoftheforest-woodsectorinSouthAfricaiswidely undeveloped, and can be increased by carbon sequestration3 in forests on previously not-afforested areas, carbon sequestration in wood products, an increased forest biomass use for energy production, and also by a further reduction of the carbon footprint of forest operations and timber transport.•A‘multiplebenefits’approachmustbeconsidered.Suchanapproachshould be able to provide an optimal portfolio of land-use forms in an area which could integrate production, environmental, climate change adaptive, sequestration and mitigation objectives and socio-economic aspects for sustainable landscape management. •Alternativeformsofsilviculture,suchasmixedspeciesforests,agroforestry, and the use of adapted indigenous tree species could yield more resilient forests in areas where site development uncertainty is high or water use restrictions prohibit use of fast growing plantation species.

Conservation and Tourism

•Climatechangeprojectionsneedtofeedintosectorlong-termmanagement plans.•Buildingpartnershipstoenableeffectivemanagementofareasnotunder formal protection, and investment in the expansion of key protected areas.•Increasingawarenessofthevalueofusingbiodiversityinassistingsocietal adaptation to the adverse impacts of climate change.

3 the natural removal of carbon dioxide from the atmosphere by the soil and plants

S e l e c t e d e x a m p l e s o f a d a p t a t i o n m e a s u r e s b y s e c t o r

31

Health •Adaptationsareurgentlyneededthatwillguaranteeadequateandreasonable healthcare delivery services – addressing all aspects of South Africa’s complex health burden, not merely the impacts of climate change.•Improvedhousingandinfrastructureinbothruralandurbancommunities should particularly aim to reduce risk of water-borne disease, exposure to indoor pollution, and support of existing public health infrastructure initiatives. •Efficientandeffectivemeteorological,waterandairqualitymonitoring services are an essential component of an early-warning adaptive and disease mitigation strategy. •Primaryhealthactivitiesfordiseasepreventionaswellasthecollectionand dissemination of health information.

Municipality and Planning

Although national and sectoral policies and plans guide and direct climate change responses, real, on the ground climate change mitigation and adapta-tion will be pioneered and driven by local municipalities.

•Describeandprioritisewhatadaptationinterventionsmustbeinitiated, who should be driving these interventions and how implementation will be monitored.•Incorporateclimateinformationintoallmunicipalplans•ComplywithobligationsaspertheDisasterManagementAct,veldand forest fire management.•Avoidbuildinginfloodlineareas;andinvestigatepossiblerevisionstoflood line estimations.•Investigateandprioritizeexistingandplannedstrategiesandactionsthat indirectly support climate change adaptation.•Designandmaintenanceofstormwaterinfrastructure.•Demand-sidewatermanagement•Municipaldevelopmentstoincludewaterandenergysavings•LocalEconomicDevelopmentstrategiesthatincorporateclimaterealities

Water •Sector-specificstrategicadaptationtolongertermclimatechangesinclude enhanced water storage capacity and increased water supply for the water sector, as well as improved catchment management (e.g. removal of invasive alien species). The Second National Communication states, significantly, that “The Water Act, the water management institutions that it creates, and the ongoing commitment to the delivery of basic water supply and sanitation infrastructure all have high relevance for adaptation” •Expandedrainwaterharvesting,waterstorageandconservationtechniques, water reuse, desalination, water-use and irrigation efficiency. •Waterconservation(WC)andwaterdemandmanagement(WDM)strategies are becoming a fundamental part of adaptation at the household level.•ImprovedunderstandingofSouthAfrica’swaterbalance,waterdemand management, as well as strengthening engineering and community based capacity to respond to new water supply challenges.•DWAF(2008)statesthatpriorityneedstobegiventodevelopingrobust strategies to ensure that demand matches supply, even where water availability is reduced. •Institutionsneedtoencourageappropriatetechnologythatrangefrom large-scale water provision for economic growth through to micro-level processes to provide water to rural development.


IPCC (2001) Climate Change 2001: Synthesis Report. A contribution of Working Groups I, II and III to the Third

AssessmentReportoftheIntergovernmentalPanelonClimateChange.UK:CambridgeUniversityPress.

IPCC (2007) Climate change 2007: Synthesis Report, Contribution of Working Groups I, II and III to the Fourth

AssessmentReportoftheIntergovernmentalPanelonClimateChange.UK:CambridgeUniversityPress.

Steffen,W.,Sanderson,A.,Tyson,P.D.,Jäger,J.,Matson,P.A.,Moore,B.,Oldfield,F.,Richardson,K.,Schellnhuber,

H.J., Turner, B.L. and Wasson, R.J., 2001: Global Change and the Earth System: A Planet Under Pressure, IGBP

ScienceSeries4,Springer-Verlag,NewYork.

F u r t h e r R e a d i n g

The Kruger to Canyons Project Website

www.sarva.org.za/k2c

The South African Risk and Vulnerability Atlas

www.sarva.org.za

Climate System Analysis Group

www.csag.uct.ac.za

Intergovernmental Panel on Climate Change

www.ipcc.ch

United Nations Framework Convention on Climate Change

www.unfcc.int

Oxfam International

http://www.oxfam.org/climatechange

United Nations Environmental Programme

www.unep.org/climatechange

Greenpeace

www.greenpeace.org/~climate

WWF

www.panda.org/climate

Glossary of Climate Change Terms

http://nsidc.org/arcticmet/glossary/climate_change.html

U s e f u l C l i m a t e C h a n g e R e s o u r c e s

Website: www.sarva.org.za/k2c

Contact:

Claire Davis: [email protected]

Climate Change Research Group,

Natural Resources and the

Environment, CSIR

Nikki Stevens: [email protected]

Climate Change Research Group,

Natural Resources and the

Environment, CSIR

compiled by - redelijk eigenzinnig · compiled by: claire davis, climate change research group, ......

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