1. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 1 A Short Overview of the IPCC Report on Climate Change Mitigation 2007 (WG III) Prof. Dr. Olav Hohmeyer Universität Flensburg Vice Chair WG III IPCC

2. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 2 Structure of the presentation Anthropogenic climate change New results on climate change in 2007 (WG I) New results on climate change mitigation 2007 (WG III): –The need for mitigation –The timeframe for mitigation –The means for mitigation –The cost of mitigation Mitigation and innovation Conclusions

3. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 3 Anthropogenic climate change

4. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 4 The greenhouse effect Source: Houghton 2001

5. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 5 Source: IPCC 2007a (WG I, SPM, p. 3) Anthropogenic Influences on Climate Change CO 2, CH 4 and N 2 O Concentrations - far exceed pre-industrial values - increased markedly since 1750 due to human activities Relatively little variation before the industrial era

6. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 6 New results on climate change in 2007 (WG I)

7. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 7 CO 2 CH 4 Long term changes in THG concentrations The atmospheric concentration of CO 2 and CH 4 in 2005 exceeds by far the natural range of the last 650,000 years Source: Pachauri und Jallow, 6.2.2007

8. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 8 Global GHG emissions 1970 - 2004 Source: IPCC 2007 (TS WG III, p. 4)

9. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 9 Structure of global GHG emissions in 2004 Source: IPCC 2007 (TS WG III, p. 4)

10. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 10 Regional distribution of per capita GHG emissions in 2004 Source: IPCC 2007 (TS WG III, p. 8)

11. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 11 Increased global temperature change Source: IPCC 2007a (WG I TS p, 37) Wärmste 12 Jahre seit 1850: 1998,2005,2003,2002,2004,2006, 2001,1997,1995,1999,1990,2000

12. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 12 Different Scales Arctic vs Global annual temperature anomalies (°C) Source: Pachauri und Jallow, 6.2.2007 Warming in the Arctic is double that for the globe from 19 th to 21 st century and from late 1960s to present. Warmth 1925 to 1950 in Arctic was not as widespread as recent global warmth.

13. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 13 Source: IPCC 2007a (WG I TSp.62) Anthropogenic and natural forcings

14. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 14 Components of radiative forcing Source: IPCC 2007a (WG I, SPM p.4)

15. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 15 New results on climate change mitigation 2007: The need for mitigation

16. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 16 Source: IPCC 2007a (WG I, SPM p.14) Projections of Future Changes in Climate Best estimate for low scenario (B1) is 1.8°C (likely range is 1.1°C to 2.9°C), and for high scenario (A1FI) is 4.0°C (likely range is 2.4°C to 6.4°C). Broadly consistent with span quoted for SRES in TAR, but not directly comparable

17. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 17 New results on climate change mitigation 2007: The timeframe for mitigation

18. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 18 New stabilization scenarios Source: IPCC 2007 (TS WG III, p. 19)

19. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 19 Emissions for stabilization levels of 445 – 570ppmv CO 2 eq. Source: IPCC 2007 (SPM WG III, p. 23)

20. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 20 Arctic ice loss faster than forecast by AR4 Quelle: Stroeve et al. 2007 S.2

21. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 21 New results on climate change mitigation 2007: The means for mitigation

22. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 22 Global economic mitigation potential 2030 Source: IPCC 2007 (SPM WG III, p. 11) Source: IPCC 2007 (SPM WG III, p. 10)

23. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 23 Global sectoral economic mitigation potential 2030 Quelle: IPCC 2007 (SPM WG III, p. 14)

24. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 24 Contributions to cumulated emission reductions until 2030 and 2100 - 650 and 490-550ppmv CO2-eq Source: IPCC 2007 (SPM WG III, S. p5) Prof. Dr. Olav Hohmeyer: IPAC: Policy Assessment Model for China IMAGE: Integrated Model of Global Climate Change (RIMV) MESSAGE: IIASA integrated modelling framework AIM: Asian-Pacific Integrated Model Prof. Dr. Olav Hohmeyer: IPAC: Policy Assessment Model for China IMAGE: Integrated Model of Global Climate Change (RIMV) MESSAGE: IIASA integrated modelling framework AIM: Asian-Pacific Integrated Model

25. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 25 Mitigation potential in the energy sector by 2030 Source: IPCC 2007 (SPM WG III, p. 17)

26. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 26 Mitigation potential in the energy sector by 2030 Source: IPCC 2007 (SPM WG III, p. 17/18)

27. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 27 New results on climate change mitigation 2007: The cost of mitigation

28. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 28 Global macro-economic mitigation costs for 2030 and 2050 source: IPCC 2007 (SPM WG III, p. 15)

29. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 29 Global macro-economic mitigation costs for 2030 and 2050 Source: IPCC 2007 (SPM WG III, p. 26)

30. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 30 Mitigation and innovation

31. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 31 Technology development, innovation and mitigation Source: IPCC 2007 (SPM WG III, p. 24)

32. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 32 Conclusions

33. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 33 Conclusions Climate change is developing faster than we thought GHG concentrations need to be stabilized at even lower levels (455 – 490 ppmvCO2eq) to avoid serious damages The necessary mitigation technologies are available Mitigations costs need to be further reduced Mitigation will be cheaper than thought before Innovation will play a crucial role in cost reductions

34. Prof. Dr. Olav Hohmeyer IPCC AR4 (2007) Results WG III Folie 34 Thank you for your attention!