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Center of Ocean-Land-Atmosphere studies. CLIM 101: Weather, Climate and Global Society. Projected Regional Changes. Jagadish Shukla. Lecture18: Oct 30, 2008. Main threat to a sustainable Earth. Arctic summer sea ice likely to disappear in second half of century
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Center of Ocean-Land-Atmosphere studies CLIM 101: Weather, Climate and Global Society Projected Regional Changes Jagadish Shukla Lecture18: Oct 30, 2008
Main threat to a sustainable Earth • Arctic summer sea ice likely to disappear in second half of century • Dynamic instability of Greenland ice sheets • Very likely increase in heat waves • Likely increase in intensity of tropical storms • Etc… SST
Main threat to a sustainable Earth • Damages from business-as-usual scenario would be at least 5% and up to 20% of Global GDP a year • Costs of removing most of the climate risk are around 1% of GDP per year • This is equivalent to paying on average 1% more for what we buy • “We can grow and be green” Sir Nicholas Stern
Main threat to a sustainable Earth • According to IPCC AR4/WGIII, the cost of avoiding the worst would be only a fraction of what Stern Report projected
Sustainability issues – LDCs • China, India and Brazil: now among the main drivers of the world’s economy China’s GDP has grown on average 9.6% per year in the last quarter century China replaced EU as the main importer of Brazilian soybeans Nepstad et al., Conservation Biology (2006)
Cultivated land area went from 1,307,400 km² in 1991 to 1,282,400 km² in 2000 Construction accounted for 56.6% of reduction 60% of China’s 669 cities face water scarcity Sustainability issues – LDCs Economic losses due to pollution in China amounted to US$ 12.8 billion annually – 1.4% of GDP (1990-1998) Source: Gaoming Jiang & Jixi Gao, 2007
Sustainability issues - LDCs • 2006: 2.6% increase in global CO2 from fossil fuel • Mainly due to 4.5% increase in coal consumption • China contributed more than two-thirds • China’s CO2 emissions surpassed those of the USA by 8% Total emissions LDCs are now part of the problem and part of the solution
Sustainability issues - LDCs Per capita emissions US But LDCs: small contribution to climate change, at least in per capita terms China Remember 1992 UNFCCC: “Common but differentiated responsibilities”
Impacts hit the poor hardest • 30 to 200 million people at risk of hunger with temperature rises of 2 to 3°C • 0.7 to 4.4 billion people will experience growing water shortages with a rise of 2°C Yields across Africa and Western Asia may fall by 15% to 35%
Impacts hit the poor hardest Climate impacts will decrease water availability and drought in semi-arid latitudes “It’s exactly what we don’t want; it makes the world much less even, more inequitable” Martin Parry, co-chair IPCC WGII
Purification of air and water Mitigation of droughts and floods Preservation of soils Pollination of crops and vegetation Dispersal of seeds Challenges to be addressed ECOSYSTEM SERVICES • Cycling and movement of nutrients • Control of potential agricultural pests • Maintenance of biodiversity • Protection of coastal shores erosion • Stabilization of climate etc.
Sustainability issues – LDCs • Under threat: Cerrado, Brazilian savanna • One of Brazil’s two biodiversity hotspots • At the current rate of loss, gone by 2030 CI/Nature
Impacts hit the poor hardest • Adaptation will cost LDCs $10 bns anually • Even more for the necessary infrastructure
Impacts hit the poor hardest • Nearly 200 million people live in coastal flood zones at risk • South Asia alone: more than 60 million people Source: Gordon et al., 2004
Impacts Future climate change will affect water availability, increasing water stress in already stressed regions...
Extreme rainfall variability: the case of Kenya Kenya: extreme rainfall variability around mean 160% 140% 120% 100% 80% 60% 1956 1958 1960 1962 1964 1966 1968 1970 1972 1974 1976 1978 1980
Kenya’s97-98 flood & 1998-2000 drought Hirji et al, World Bank (2003)
Mozambique’s2000 floods Real GDP - 23%
Correlation between GDP and Rainfall in Zimbabwe Rainfall affects growth…. the case of Zimbabwe
Temperature and Precipitation Changes over North America(A1B )
Temperature and Precipitation Changes over South America(A1B )
PROJECTED SCENARIOS OF DEFORESTATION ... 50% 20% Control 40% 60% 80% 100% or Soybean Vegetation classification Dorman and Sellers (1989) Sampaio et al., 2007 Source: Soares-Filho et al., 2006 and Amazon Scenarios Project, LBA
Annual Surface Temperature Changes (A1B ) 2080 to 2099 minus 1980 to 1999
GEC goes beyond climate change Global dust deposition Jickells et al. (2005)
2060s observations HadCM3 Medium-High (SRES A2) 2040s 2003 Temperature anomaly (wrt 1961-90) °C GEC is more acute than ever • 2003 • Heat wave hits Europe • 30,000 people die in Western Europe
Main threat to a sustainable world • Arctic summer sea ice likely to disappear in second half of century • Very likely increase in heatwaves • Likely increase in intensity of tropical storms SST
Heat stress • Drought stress • Wildfires Case study: Summer heat wave 2003 Schär et al. 2004 Precipitation Max. temperature August 2003 Rebetez et al. 2006
THANK YOU! ANY QUESTIONS? Center of Ocean-Land-Atmosphere studies