1. 1Climate Change and Disaster Risk Science and impacts Session 1 World Bank Institute Maarten van Aalst

2. 2Climate Change and Disaster Risk Climate change and its implications for disaster risk 1. Rising use of fossil fuels (oil, coal, gas) 2. Rising concentrations of greenhouse gases in the atmosphere 3. Rising temperatures (global warming) 4. Changes in local average climate (warmer, changing rainfall, higher sea levels, etc.) 5. Changes in local risk of extremes (heat wave, flood, drought, storm, etc.) CHANGING VULNERABILITY CHANGING DISASTER RISK 6. Socio-economic circumstances, natural resources, political stability, etc. (A) (B) (C)

3. 3Climate Change and Disaster Risk Disaster trends 100 200 300 0 geo physical Number of disasters hydro- meteorological 400 ‘90 Source: CRED ‘91‘92‘93‘94‘95‘96‘97‘98‘99‘00‘01‘02‘03‘04‘05‘06 epidemics, insect infestations

4. 4Climate Change and Disaster Risk The greenhouse effect

5. 5Climate Change and Disaster Risk The earth is warming Warmest 12 years: 1998,2005,2003,2002,2004,2006, 2001,1997,1995,1999,1990,2000

6. 6Climate Change and Disaster Risk 1928 2004 Upsala glacier, Argentina Source: Greenpeace

7. 7Climate Change and Disaster Risk Rain and snowfall patterns Smoothed annual anomalies for precipitation (%) over land from 1900 to 2005; other regions are dominated by variability. Increases Decreases

8. 8Climate Change and Disaster Risk 2020 Black: observations Red curve: Climate model simulation with all changes, including human influence Blue curve: Climate model simulation with only natural changes (sun, volcanoes) Black: observations “ Most of the observed increase in globally averaged temperatures since the mid-20th century is very likely due to the observed increase in anthropogenic greenhouse gas concentrations”

9. 9Climate Change and Disaster Risk Temperature projections for 2100 Low scenario (B1): 1.8°C (likely range 1.1°C to 2.9°C) High scenario (A1FI): 4.0°C (likely range 2.4°C to 6.4°C)

10. 10Climate Change and Disaster Risk 2020 Regional temperature projections

11. 11Climate Change and Disaster Risk Increases in rainfall very likely in high latitudes Decreases in rainfall likely in most subtropical land regions Changes in rainfalls patterns

12. 12Climate Change and Disaster Risk Severe implications

13. 13Climate Change and Disaster Risk Implication of extremes (a) more warm days and heat waves Heat Wave Summer 2003 Europe Warmer and more frequent hot days and nights over most land areas (virtually certain) More heat waves over most land areas (very likely)  Increased incidence of death and serious illness in older age groups and urban poor  Increased electric cooling demand and reduced energy supply reliability  Increased risk of damage to a number of crops  Increased heat stress in livestock and wildlife  Shift in tourist destinations

14. 14Climate Change and Disaster Risk Increase in mean temperature…….

15. 15Climate Change and Disaster Risk Implication of extremes (b) less and warmer cold days Warmer and fewer cold days, and nights over nearly all land areas (already observed: very likely, projected for coming decades: virtually certain)  Decreased cold-related human morbidity and mortality  Decreased risk of damage to a number of crops, and increased risk to others  Extended range and activity of some pest and disease vectors (e.g., malaria, dengue)  Reduced heating energy demand

16. 16Climate Change and Disaster Risk Implication of extremes (c) more heavy rainfall and snow Frequency of heavy precipitation events increases over most areas (already observed: likely, projected for coming decades: very likely)  Increased flood, landslide, avalanche, and mudslide damage  Increased soil erosion  Increased flood runoff could increase recharge of some floodplain aquifers  Increased pressure on public and private flood insurance systems and disaster relief

17. 17Climate Change and Disaster Risk Implication of extremes (d) more droughts Area affected by droughts increases (already observed: likely, in many regions projected for coming decades)  Decreased crop yields  Increased damage to building foundations caused by ground shrinkage  Decreased water resource quantity and quality  Increased risk of forest fire

18. 18Climate Change and Disaster Risk The most important spatial pattern (top) of the monthly Palmer Drought Severity Index (PDSI) for 1900 to 2002. The time series (below) accounts for most of the trend in PDSI. Drought is increasing most places

19. 19Climate Change and Disaster Risk Implication of extremes (e) heavier tropical cyclones Increase in tropical cyclone peak wind intensities, mean and peak precipitation intensities (already observed: likely, in some areas projected for coming decades: likely)  Increased risks to human life, risk of infectious disease epidemics, and many other risks  Increased coastal erosion and damage to coastal buildings and structures  Increased damage to coastal ecosystems such as coral reefs and mangroves

20. 20Climate Change and Disaster Risk Implication of extremes (f) extreme high sea levels Increased incidence of extreme high sea levels (already observed: likely, projected for coming decades: likely)  Increased coastal erosion and damage to coastal buildings and structures  Saltwater intrusion, impacts on agriculture and drinking water

21. 21Climate Change and Disaster Risk Implication of extremes (g) circulation changes Climate change is affecting storm tracks, winds and temperature patterns

22. 22Climate Change and Disaster Risk Some aspects of climate have not been observed to change  Tornadoes  Dust-storms  Hail  Lightning

23. 23Climate Change and Disaster Risk Operational relevance of climate information  Most of the information is not at the scale we might want for field applications, although some important broad trends are getting clearer (e.g., “more variability in rainfall”)  Disaster managers and development planners should note the significant rise in risks. However, they should not expect (and do not need!) perfect climate information to manage that rise in risks.