Transcript Climate change and Africa

CLIMATE CHANGE IN AFRICA:
SCIENCE, RISK AND VULNERABILITY
Dr Lisa Frost Ramsay ([email protected])
“New studies confirm that Africa is one of the
most vulnerable continents because of the range
of projected impacts, multiple stresses and low
adaptive capacity.”
(IPCC, 2007)
What does the science say about
Africa?
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By 2020, between 75 and 250 million people living in Africa are
projected to be exposed to increased water stress due to climate
change.
By 2080, an increase of 5 to 8% of arid and semi-arid land in
Africa is projected under a range of climate scenarios (high
confidence).
By 2020, in some countries, yields from rain-fed agriculture could be
reduced by up to 50%. Agricultural production (and access to food)
in many African countries is projected to be severely compromised.
Towards the end of the 21st century, projected sea level rise will
affect low lying coastal areas with large populations. The cost of
adaptation could amount to at least 5 to 10% of GDP.
Figure 1: Projections of changes in rainfall for the period of 2090-2099 relative to the present
with Dec-Feb on the left and June-Aug on the right (IPCC, 2007)
Figure 2: Changes in water availability for the period 2090-2099 relative to the present
(IPCC, 2007)
What does the science say about
South Africa specifically?
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General warming across the country
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Sea level rise in coastal zone
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No long term change in average rainfall across South Africa
expected (Joubert et al., 1996 and Foucheareau, 2007)
(however IPCC, 2007 suggests overall drying)
 Regional impacts
 Temporal impacts
Extremes in rainfall variability (daily, seasonal and interannual)
  intense rainfall events,  number of rain-days
 Extreme droughts and flooding events (IPCC, 2007)
Droughts…
Stronger
Flooding…
global signal since
the 1970s
Increased correlation
with El Nino events
 Long term variations in
SST
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(Faucherau et al., 2003)
http://www.weathersa.co.za/References/elnino.jsp
 Tropical
cyclones
reaching higher latitudes
(Pittock and Salinger,
1991)
 Increased frequency and
intensity of cut-off lows
(Mason et al., 1999)
 Convective storms…
tornadoes? (Hunter,
2008)
A Hint of Things to Come…?
Lake St Lucia - 1991
Molweni – 2008
Mozambique – 2000
Northern Province - 1982
Why is Africa so vulnerable?
Figure 2: Changes in water availability for the period 2090-2099 relative to the present
(IPCC, 2007)
Climate change risks in Africa
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Scientific research tells us about the environmental hazards associated with
climate change
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Droughts
Floods
Storms – lightning, hail, tornadoes
Sea level rise
Etc - MULTIPLE IMPACTS
But the story doesn’t stop there...
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Risk is the combination of this hazard and community susceptibilities to impact
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Economic and political factors
Behaviours – social and cultural factors
Vulnerability combines risk with resilience
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Adaptability and the potential to ‘bounce back’
Risk and Vulnerability
Risk = hazard level + susceptibility to exposure
AND
Vulnerability = risk + resilience
Risk and vulnerability in Africa
Susceptibility?
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A direct relationship with the environment
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Resilience?
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Subsistence farming
Lack of economic support – insurance, loans,
savings
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Existing poverty issues – multiple stresses
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Overpopulation
Overgrazing and soil erosion
Background health issues and malnutrition
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Long lifestyle histories – cultural even
psychological implications of change
No experience of the severity of disasters
expected in the next 50 years
Housing structures
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Entire communities invested in one type of resource
Traditional lifestyles and adaptability
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Living from year to year (day to day!)
‘All their eggs in one basket’
Construction issues
Location issues (e.g on the water’s edge)
Research and communication
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Preparedness
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Political instabilities
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Pushing fragile political systems ‘over the edge’ –
war?
Adaptation is not enough
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Dependence on international decisions and strategies
Timeframes of mitigation strategies – probably
longer than communities can wait
Figure 3: Climate change interrelationships (IPCC, 2007)
Adaptation and Mitigation
“There is high confidence that neither adaptation nor
mitigation alone can avoid all climate change impacts…
Adaptation is necessary both in the short term and longer
term to address impacts resulting from the warming that
would occur even for the lowest stabilisation scenarios
assessed…
Adaptation and mitigation can complement each other and
together can significantly reduce the risks of climate
change.” (IPCC, 2007).