Science and impacts

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

2. Climate change and its implications for disaster risk 2. Rising concentrations of greenhouse gases in the atmosphere 3. Rising temperatures (global warming) 1. Rising use of fossil fuels (oil, coal, gas) 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.) 6. Socio-economic circumstances, natural resources, political stability, etc. (B) (A) CHANGING VULNERABILITY CHANGING DISASTER RISK (C) Climate Change and Disaster Risk

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

4. The greenhouse effect Climate Change and Disaster Risk

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

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

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

8. 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” Black: observations Red curve: Climate model simulation with all changes, including human influence 2020 Climate Change and Disaster Risk

9. 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) Climate Change and Disaster Risk

10. Regional temperature projections 2020 Climate Change and Disaster Risk

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

12. Severe implications Climate Change and Disaster Risk

13. Implication of extremes (a) more warm days and heat waves 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 Heat Wave Summer 2003 Europe Climate Change and Disaster Risk

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

15. 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 Climate Change and Disaster Risk

16. 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 Climate Change and Disaster Risk

17. 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 Climate Change and Disaster Risk

18. Drought is increasing most places 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. Climate Change and Disaster Risk

19. Implication of extremes (e) heavier tropical cyclones Increase in tropical cyclone peak wind intensities, meanand 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 Climate Change and Disaster Risk

20. 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 Climate Change and Disaster Risk

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

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

23. 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. Climate Change and Disaster Risk