1. WHAT WOULD BE THE IMPACTS OF CLIMATE CHANGE ASSUMING NO, OR SOME, OR MUCH EMISSIONS CONTROL AND SEQUESTRATION? Martin parry Co-Chair, Working Group II, IPCC

2. Global mean temperature predictions Ensembles of four predictions of global mean temperature resulting from business as usual changes in greenhouse gases following on from observed changes since 1860 (orange curves). The addition of sulphate aerosol cooling is shown in the red curves. Hadley Centre for Climate Prediction and Research

3. Global mean precipitation predictions Ensembles of four predictions of precipitation (rainfall and snowfall) resulting from business as usual changes in greenhouse gases following on from observed changes since 1860 (blue curves). The addition of sulphate aerosol cooling is shown in the green curves. Hadley Centre for Climate Prediction and Research

4. Change in annual temperatures for the 2050s The change in annual temperatures for the 2050s compared with the present day, when the climate model is driven with an increase in greenhouse gas concentrations equivalent to about a 1% increase per year in CO 2. The picture shows the average of four model runs with different starting conditions. Hadley Centre for Climate Prediction and Research

5. Observed change in annual precipitation for the 2050s The change in annual precipitation for the 2050s compared with the present day, when the climate model is driven with an increase in greenhouse gas concentrations equivalent to about a 1% increase per year in CO 2. The picture shows the average of four model runs with different starting conditions. Hadley Centre for Climate Prediction and Research

6. IMPACTS UNDER NO MITIGATION

7. Annual runoff Percentage change in 30-year average annual runoff by the 2080s. Percentage change in 30-year average annual runoff by the 2080s. University of Southampton

8. Population under extreme water stress Change, due to climate change, in the number of people living in countries with extreme water stress. 0 40 80 120 2020s 2050s 2080s Population (millions) University of Southampton

9. Crop yield change 2020s, ) 2050s,2080s

10. 2020s2050s2080s % change in prices from 1990 baseline 10 8 6 4 2 0 – 2 2020s2080s2020s2080s 4000 4200 3800 3600 3400 3200 3000 2800 2600 2400 2050s Cereal production (mmt) Reference scenario Climate change scenario 2020s2050s2080s Additional millions of people at risk of hunger 50 45 40 35 30 25 20 15 10 5 0 Additional people at risk of hunger under the climate change scenario (0 = Projected reference case). Projected global cereal production for reference case and the climate change scenario. Percentage change in global cereal prices under the climate change scenario (0 = Projected reference case).

11. People at risk from sea-level rise Percentage change in the number of people at risk under the sea-level rise scenario and constant (1990s) protection (left bar) and the sea-level rise scenario and evolving protection (right bar). 2050s2020s2080s 700 400 500 600 100 300 200 0 % increase Middlesex University / Delft Hydraulics

12. IMPACTS UNDER SOME/MUCH MITIGATION

13. Emissions and concentrations of CO 2 from unmitigated and stabilising emission scenarios Unmitigated emissions 750 ppm stabilisation550 ppm stabilisation Hadley Centre for Climate Prediction and Research

14. Global average temperature rise from unmitigated and stabilising emission scenarios 1900200021002200 0 2 4 Global temperature change (°C) 3 1 Unmitigated emissions 750 ppm stabilisation550 ppm stabilisation Hadley Centre for Climate Prediction and Research

15. Temperature rise Annual average, from the present day to the 2080s Hadley Centre for Climate Prediction and Research c Unmitigated Emissions c c Stabilisation of CO 2 at 550ppm Stabilisation of CO 2 at 750ppm

16. Change in precipitation Annual average, from the present day to the 2080s c Unmitigated Emissions c c Stabilisation of CO 2 at 550ppm Stabilisation of CO 2 at 750ppm Hadley Centre for Climate Prediction and Research

17. Changes in river runoff from the present day to the 2080s Unmitigated emissions Stabilisation of CO 2 at 750 ppm Stabilisation of CO 2 at 550 ppm –75–50–25–5 to 5255075 Change in annual runoff (%) University of Southampton

18. Changes in water stress from the present day to the 2080s 011223344 Billions of people Increased water stress Decreased water stress University of Southampton Unmitigated Emissions 750 ppm Stabilisation550 ppm Stabilisation

19. Changes in crop yield from the present day to the 2080s Unmitigated emissions Stabilisation of CO 2 at 750 ppm Stabilisation of CO 2 at 550 ppm University of East Anglia Potential change in cereal yields (%) 10 – 5 0 – -2.5 -5 – -10 -2.5 – -5 -10 – -20 2.5 – 0 5 – 2.5 No data

20. Global number of people flooded under three emissions scenarios 100 80 60 40 20 0 People flooded (millions/year) 2020s2050s2080s Unmitigated emissions 750 ppm stabilisation550 ppm stabilisation University of Middlesex No climate change

21. People flooded by region 60 0 10 20 30 40 50 Southern Mediterranean West Africa East Africa South Asia SE Asia People flooded (millions/year) Unmitigated emissions 750 ppm stabilisation550 ppm stabilisation No climate change University of Middlesex

22. Island people flooded 600 500 400 300 200 100 0 Caribbean Indian Ocean small islands Pacific small islands People flooded (thousands/year) University of Middlesex Unmitigated emissions 750 ppm stabilisation550 ppm stabilisation No climate change

23. Malaria transmission Change in duration of season, 2080s Unmitigated emissions Stabilisation at 750 ppm Stabilisation at 550 ppm 2 to 5 months1 to 2 months–2 to –1 months–5 to –2 months London School of Hygiene and Tropical Medicine

24. Millions at Risk in the 2080s

25. The Cost of Stabilising CO 2 Concentrations

26. The effect of different global economic pathways Regional enterprise: high pop, mod. growth, (A2) Local stewardship: semi- sustainable dev, low pop (B2)

27. A2 in 2050s B2 Pop 11.3 billion Pop 11.3 billion GDP 82 tr $ GDP 82 tr $ primary energy 970 GJ/yr primary energy 970 GJ/yr carbon 16 GtC/yr carbon 16 GtC/yr Pop 9.3 billion Pop 9.3 billion GDP 110 tr $ GDP 110 tr $ primary energy 870 GJ/yr primary energy 870 GJ/yr carbon 11 GtC/yr carbon 11 GtC/yr

28. Additional People at Risk of Hunger under the SRES A2 and B2 Scenarios

29. Costs of 550 Stabilisation assuming different development pathways

30. Conclusions : Stabn at 750 does not avoid most effects. Stabn at 750 does not avoid most effects. Stabn at 550 does, but at considerable cost (= c.20 times Kyoto reductions). Stabn at 550 does, but at considerable cost (= c.20 times Kyoto reductions). Sustainable development (cf SRES B2 pathway) needs also to be part of the solution Sustainable development (cf SRES B2 pathway) needs also to be part of the solution

31. The Shortfall in Global Cereal Production for Reference Case and the SRES Scenarios

32. Millions at Risk in the 2050s

33. Conclusions : 2 Invest in adaptation, to increase resilience to climate change: technology (eg GM), engineering (eg water use efficiency), institutions. These are win-win (eg drought-proofing). Invest in adaptation, to increase resilience to climate change: technology (eg GM), engineering (eg water use efficiency), institutions. These are win-win (eg drought-proofing). Invest especially in key vulnerable regions and sectors: Africa, Indian subcont., small islands; water, food, coastal settlement. Invest especially in key vulnerable regions and sectors: Africa, Indian subcont., small islands; water, food, coastal settlement. Revise the adaptation/mitigation emphasis: Revise the adaptation/mitigation emphasis:

34. Change in vegetation biomass from present day to the 2230s –8–5–3–11358 kgC/m 2 ITE Edinburgh c Stabilisation of CO 2 at 550ppm Stabilisation of CO 2 at 750ppm c

35. Vegetation dieback Unmitigated emissions 750 ppm stabilisation550 ppm stabilisation ITE Edinburgh

36. Uptake of carbon by vegetation 5 4 3 2 1 0 –1 –2 –3 1950205020002100215022002250 Transfer of carbon to vegetation (GtC/yr) Unmitigated emissions 750 ppm stabilisation550 ppm stabilisation ITE Edinburgh

37. Changes in vegetation biomass between the present day and the 2080s –8–5–3–11358 kgC/m 2 –8–5–3–11358 kgC/m 2 –8–5–3–11358 kgC/m 2 00.11351015 kgC/m 2 ITE Edinburgh Unmitigated EmissionPresent Day Stabilisation of CO2 at 750 ppmStabilisation of CO2 at 550 ppm

38. Changes in river runoff from the present day to the 2230s –75–50–25–5 to 5255075 Change in annual runoff (%) University of Southampton c Stabilisation of CO 2 at 550ppm Stabilisation of CO 2 at 750ppm c

39. Changes in water stress from the present day to the 2080s Unmitigated emissions Stabilisation of CO 2 at 750 ppm Stabilisation of CO 2 at 550 ppm Stressed country with decrease in stress Country moves to stressed class Stressed country with increase in stress University of Southampton

40. Conclusions : 3 Foster adaptation to avoid increased inequality (autonomous adaptn=more unequal effects of climate change). Foster adaptation to avoid increased inequality (autonomous adaptn=more unequal effects of climate change). Foster increased resilience (especially in the tail): a) seek the sub-optimal (eg drought resistant/non-max yield crop varieties); b) (many) small vs (few) large actions; c) promote stability (vs growth?). Foster increased resilience (especially in the tail): a) seek the sub-optimal (eg drought resistant/non-max yield crop varieties); b) (many) small vs (few) large actions; c) promote stability (vs growth?).

41. Rate of sea-level rise 2080s2110s2140s2170s2200s2230s Rate of sea-level rise (cm/century) Unmitigated emissions 750 ppm stabilisation550 ppm stabilisation

42. Global wetland losses 20 15 10 5 0 2020s2050s2080s2110s2140s2170s2200s2230s Fraction of wetland area lost (%) Unmitigated emissions 750 ppm stabilisation550 ppm stabilisation University of Middlesex

43. Coastal flooding Change from the present day to the 2080s Unmitigated emissions Stabilisation at 750 ppm Stabilisation at 550 ppm University of Middlesex

44. Malaria transmission season Estimated for the present day (falciparum) London School of Hygiene and Tropical Medicine

45. People at risk of malaria additionally from climate change 350 300 250 200 150 100 50 0 2020s2050s2080s Additional people at risk (millions) Unmitigated emissions 750 ppm stabilisation550 ppm stabilisation London School of Hygiene and Tropical Medicine