1. 1 IPCC WMO UNEP Dr. R K Pachauri Chairman, Intergovernmental Panel on Climate Change Director-General, The Energy and Resources Institute Director, Yale Climate & Energy Institute Croatia 28th March 2011 THE IMPORTANCE OF SCIENCE IN CLIMATE CHANGE NEGOTIATIONS: SCIENCE FOR A BETTER WORLD

2. 2 IPCC THE INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE (IPCC): MISSION AND PROCESS

3. 3 IPCC Mandate of the IPCC “The General Assembly […] endorses action of the World Meteorological Organisation and the United Nations Environment Programme in jointly establishing an Intergovernmental Panel on Climate Change to provide international coordinated scientific assessments of the magnitude, timing and potential environmental and socio-economic impact of climate change and realistic response strategies […].” United Nations General Assembly 43 rd session resolution, 6 th December 1988

4. 4 IPCC Writing and review process of IPCC reports

5. 5 IPCC +130 countries 450 lead authors 800 contributing authors +2500 scientific expert reviewers +18000 peer-reviewed publications cited +90000 comments from experts and Governments The IPCC Fourth Assessment Report (2007)

6. 6 IPCC EVOLUTION OF THE SCIENCE OF CLIMATE CHANGE

7. 7 IPCC History of climate change awareness 1898: Clarion call from Swedish scientist Svante Ahrrenius 1988: NASA scientist James Hansen tells U.S. Congress that global warming "is already happening now'‘ Creation of the IPCC 1992: Adoption of the UNFCCC 1997: Approval of the Kyoto Protocol 2005: Warmest year since record-keeping began in mid-19th Century Ratification of the Kyoto Protocol 2009: COP took note of the Copenhagen Accord

8. 8 IPCC Copenhagen Accord (2009)  Recognizes scientific view that the world must not exceed a 2 °C increase in warming  States that domestic measurement, reporting and verification of mitigation actions of developing countries  Envisages establishment of a new “Copenhagen Green Climate Fund” approaching USD $30bn for 2010-2012; $100bn by 2020 But no binding agreement

9. 9 IPCC The assessments carried out by the IPCC have influenced global action on an unprecedented scale 1. First Assessment Report (1990) had a major impact in defining the content of the UNFCCC 2. The Second Assessment Report (1996) was largely influential in defining the provisions of the Kyoto Protocol 3. The Third Assessment Report (2001) focused attention on the problems of the impacts of climate change and the need for adaptation 4. The Fourth Assessment Report (2007) is creating a strong basis for the urgent need for mitigation and adaptation and a strong legally binding agreement

10. 10 IPCC Additional physics incorporated in successive climate models

11. 11 IPCC Number of papers published on climate change

12. 12 IPCC The work of the IPCC shows how science can help address problems facing humanity By creating understanding of the interrelationships between human actions and the environment By defining specific solutions that can address the problem if applied on a large scale By assessing future impacts and key vulnerabilities By defining possible scenarios of action and their consequences

13. 13 IPCC KEY FINDINGS FROM THE IPCC FOURTH ASSESSMENT REPORT (AR4)

14. 14 IPCC Carbon dioxide emissions Radiative Forcing (Wm ) Carbon Dioxide (ppm) 10000 5000 0 Time (before 2005) -2 Global atmospheric concentrations of greenhouse gasses (GHGs) increased 70% in 1970- 2004 as a result of human activities

15. 15 IPCC Observed changes Global average sea level Northern hemisphere snow cover Global average temperature

16. 16 IPCC Global temperature change 1900 1950 2000 Year Temperature anomaly 1 0.5 0 Models using only natural forcing Models using both natural and anthropogenic forcing Observations

17. 17 IPCC Continued emissions would lead to further warming of 1.1ºC to 6.4ºC over the 21 st century (best estimates: 1.8ºC - 4ºC) year Ranges for predicted surface warming

18. 18 IPCC Vulnerability of coastal deltas Extreme (> 1 million people potentially displaced by current sea-level trends by 2050) High (50 000 to 1 million) Medium (500 to 50 000)

19. 19 IPCC Projected changes in annual runoff (2041-60 relative to 1900-70)

20. 20 IPCC 20-30% of species are likely to be at risk of extinction if increases in warming exceed 1.5-2.5°C Partial loss of ice sheets on polar land could imply metres of sea level rise, major changes in coastlines and inundation of low-lying areas Abrupt or irreversible impacts

21. 21 IPCC People exposed to increased water stress by 2020:  120 million to 1.2 billion in Asia  12 to 81 million in Latin America  75 to 250 million in Africa Expected impacts on poor regions due to climate variability and change Possible yield reduction in agriculture:  30% by 2050 in Central and South Asia  30% by 2080 in Latin America  50% by 2020 in some African countries Crop revenues could fall by 90% by 2100 in Africa

22. 22 IPCC Some implications for global security Rising ethnic conflicts can be linked to competition over increasingly scarce natural resources (E.g. Jordan River) Food scarcity and the resulting increase in food prices will push poor countries into chaos  Such “failed states” can export disease, terrorism, illicit drugs, weapons and refugees By the end of the century, billions of people could be forced from their native land by rising sea levels, extreme events, floods and famines

23. 23 IPCC AVERAGE ARCTIC TEMPERATURES INCREASED AT ALMOST TWICE THE GLOBAL AVERAGE RATE IN THE PAST 100 YEARS - Annual average arctic sea ice extent has shrunk by 2.7% per decade

24. 24 IPCC THE FREQUENCY OF HEAVY PRECIPITATION EVENTS HAS INCREASED OVER MOST LAND AREAS - Rainfall in Mumbai (India), 2005: 1 million people lost their homes

25. 25 IPCC THE PROPORTION OF TROPICAL CYCLONES REACHING HIGHER INTENSITY HAVE INCREASED OVER THE PAST 3 DECADES - CYCLONE NARGIS IN MYANMAR, 2008: 100 000 ESTIMATED DEATHS

26. 26 IPCC INTENSE TROPICAL CYCLONE ACTIVITY HAS INCREASED IN THE NORTH ATLANTIC SINCE ABOUT 1970 - Hurricane Katrina, 2005: up to $200 billion cost estimate

27. 27 IPCC In the course of the century, water supplies stored in glaciers and snow cover are projected to decline - The Chacaltaya glacier, 5,300m up in the Andes, which used to be the world's highest ski run, has been reduced to just a few small pieces of ice 1996 2009 Credit: Edson Ramirez

28. 28 IPCC HEAT WAVES HAVE BECOME MORE FREQUENT OVER MOST LAND AREAS - Heat wave in Europe, 2003: 35 000 deaths

29. 29 IPCC MORE INTENSE AND LONGER DROUGHTS HAVE BEEN OBSERVED OVER WIDER AREAS SINCE THE 1970S, PARTICULARLY IN THE TROPICS AND SUBTROPICS Photo credit: GoodPlanet

30. 30 IPCC Stabilisation scenarios Stabilisation level (ppm CO 2 -eq) Global mean temp. increase (ºC) Year CO 2 needs to peak Change in global CO 2 emissions in 2050 (% of 2000 emissions) 445 – 4902.0 – 2.42000 – 2015-85 to -50 490 – 5352.4 – 2.82000 – 2020-60 to -30 535 – 5902.8 – 3.22010 – 2030-30 to +5 590 – 7103.2 – 4.02020 – 2060+10 to +60

31. 31 IPCC Mitigation measures would induce 0.6% gain to 3% decrease of GDP in 2030 Stabilisation levels (ppm CO2-eq) Range of GDP reduction (%) Reduction of average annual GDP growth rates (percentage pts) 445 - 535< 3< 0.12 535 - 5900.2 – 2.5< 0.1 590 - 710-0.6 – 1.2< 0.06 Costs of mitigation in 2030

32. 32 IPCC GDP without mitigation GDP with stringent mitigation 2030 GDP Time Current Mitigation would postpone GDP growth by one year at most over the medium term Cost of mitigation in 2030: max 3% of global GDP Impacts of mitigation on GDP growth Schematic graph

33. 33 IPCC Health co-benefits from reduced air pollution  Benefits range from 30-50% of estimated mitigation costs up to a factor of 3 to 4 More employment  Solar PV and wind-energy generate 5.7 person-years of employment per 1 million US$ investment (over ten years); while coal industry generates only 4 Increased energy security Main co-benefits of mitigation  Mitigation actions can result in near-term co-benefits that may offset a substantial fraction of mitigation costs

34. 34 IPCC Democracy must in essence therefore, mean the art and science of mobilizing the entire physical, economics and spiritual resources of all the various sections of the people in the service of the common good for all.