IPCC Caribbean Climate Change Conclusions

1. IPCC Caribbean Climate Change Conclusions Professor Anthony Chen

2. IPCC Caribbean Climate Change Conclusions Climate Change Conference UWI, Mona June 1-17,2007 A. Anthony Chen Climate Studies Group, Mona Department of Physics University of the West Indies, Mona

3. Advisory Report on Global Change: global warming …no… big…deal…have…a…nice…day…

4. Why Worry about Greenhouse Gases?

5. Greenhouse Gases in Atmosphere • Water vapor, Carbon Dioxide, Nitrous Oxide, Methane, Oxygen, Ozone, Chlorofluro-carbons • Naturally occurring and man made • They trap the radiant heat from earth, making the earth warmer • Greenhouse effect, similar to horticultural greenhouse

6. We need the greenhouse effect • Without naturally occurring greenhouse gases Earth’s temperature would be about 33ºC Colder

7. Need nearly constant amount of CO2 …But … CO2 Concentration (ppmv) CO2 Concentration in Ice Core Projected 2100 2001 Last ice age 400,000 100,000 Years before Present

8. Too much: Runaway Greenhouse effect – CO2 and H2O Vapour Increased CO2 Increased Air Temperature Evaporation Greenhouse Effect H2O vapour

9. Venus Earth Venus is almost the same size as the Earth but completely uninhabitable. A runaway greenhouse effect makes the surface 400 degrees hotter than the Earth.

10. Founded 1988 by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP) Working Group I assesses the scientific aspects of climate change. Working Group II assesses impacts, vulnerability and adaptation Working Group III assesses options for mitigating climate change.

11. IPCC Assessment Reports • 1990: First Assessment Report (FAR) • 1995: Second Assessment Report (SAR) • 2001: Third Assessment Report (TAR) • 2007: Fourth Assessment Report (AR4)

12. Contents of AR4

13. Chapter 11 • Includes section on small islands for first time: Caribbean, Indian Ocean, North and South Pacific Oceans

14. Processes to Reduce Uncertainties in Chapter 11 • Climate (average state of weather), not day to variation in weather • Assessment based on peer reviewed papers and publications up to March 2006 • Observed trends in climate • Global Circulation Models of Climate • Downscaling of global models • Regional climate models (dynamic) • Statistical downscaling • Strong Physical basis or explanation • Greater degree of certainty when more of the above agree

15. Special Report on Emission Scenarios (SRES) CO2 Emissions A2 A1B B1 2000 2100

16. AR4 Summary Statement for Caribbean region based on limited Peer Reviewed Papers and Data: • Sea levels will likely continue to rise on average during the century around the islands of the Caribbean Sea. (Models indicate that the rise will not be geographically uniform globally but large deviations among models make estimates of distribution across the Caribbean, Indian and Pacific Oceans uncertain.) • All Caribbean islands are very likely to warm during this century. The warming is likely to be somewhat smaller than the global, annual mean warming in all seasons. • Rainfall in the vicinity of the Greater Antilles is likely to decrease in JJA but changes elsewhere and in DJF are uncertain. Likely: > 66% Very likely > 90%

17. Rest of Presentation • Some details of projection for the Caribbean (Chapter 11) • Global Projections (Chapter 10 ) which may affect the Caribbean – Hurricanes, ENSO, NAO, Sea level rise • Others more recent research (non-AR4) • CSGM Regional Downscaling using PRECIS • Limitations (Needs)

18. AR4 Assessment of Observed Caribbean Temperature Change • Peterson and Taylor, et al, 2002:Journal of Geophysical Research • Significant warming trend from1950’s to 2000 • Based on UWI Climate Data workshop in 2001

19. AR4 Assessment of temperature Change • 21Global Models using SRES A1B Scenario: • Monthly Increases projected to 2090 All models give temperature rises for all months Temperature Change ºC 25% 50% 2ºC 25% Average Jan Dec

20. Global model results Supported by the work of Angeles et al, 2007, at U. of Puerto Rico, Mayaguez

21. AR4: Statistical Downscaling: Piarco Airport (T&T) Temperature projected statistically from 1960-1990 to 2080’s using A2(Cassandra Rhoden, MPhil thesis, UWI, Mona) Temp ºC 2ºC Global Statistical 1960-90 2080 Global and downscaled projected changes agree. Similarly for Worthy Park, Jamaica and Grantley Adam, Barbados

22. Post AR4 Dynamic Downscaling: Regional model simulated changes in temperature by 2080’s based on 1960 – 1990 data (Jayaka Campbell, MPhil thesis, UWI, Mona) A2 B2 3ºC 2ºC

23. Strong Physical Basis for temperature increases: Man made greenhouse gases increases the amount of heat trapped by the atmosphere:

24. Virtually certain that Caribbean temperatures will increase • Agreement of observation, global models, statistical downscaling, good physical basis • Extent will depend on actual green house gas emissions ~ 2ºC for A1B scenario, ~ 3ºC Globally • Even if emissions ceased today temperatures will rise at the end of the century due to long lifetimes of CO2 and methane and long ‘memory’ of the oceans

25. AR4 Assessment of 21 Global Models’ Projection of Changes in Precipitation from 1980’s to 2080’s using A1B Scenario Significant decrease in JJA Jul-Aug Annual Dec-Feb +50 % Change Large number of models showing decrease -50 No. of models increasing 21 0

26. AR4 Assessment: Monthly Precipitation Change over the Caribbean from 21 models using AIB from 1980’s to 2080’s 25% models give increases Increases Percentage Change Decreases Most models decrease in Jun to Aug Dec Jan

27. Precipitation Summary • Expect drying in the Greater Antilles in JJA • General Agreement between Global Models • A Global model run for the Caribbean show decrease in JJA (Angeles et al, 2007) • Some statistical runs show decreases in JJA • Drying trend in observed data (Neelin et al., 2006) • Theoretically, drying is probable in Greater Antilles (Chou and Neelin,2004) **

28. Simplified Mechanism – Wet Gets Wetter Convective adjustment -Rising air due to CO2 induced heating Reduced Rising Most model agree in JJA Some models do not agree Moisture moves in because of adjustment - wetter Moisture moves out - drier Adjacent region: Lesser Antilles Greater Antilles Near the equator

29. Precipitation Summary • Expect drying in the Greater Antilles in JJA • General Agreement between Global Models • A Global model run for the Caribbean show decrease in JJA (Angeles et al, 2007) • Some statistical runs show decreases in JJA • Drying trend in observed data (Neelin et al., 2006) • Theoretically, drying is probable in Gtr Antilles (Chou and Neelin, ** • Not enough results to make statement for rest of Caribbean and rest of the year

30. Other Results Supporting drying: • North Atlantic Oscillation (NAO) • In multimodel analysis, NAO increases • El Niño • Model consensus gives El Niño like pattern with higher temperatures in the eastern Pacific. • These conditions are associated with drying in the Caribbean.

31. North Atlantic Hurricanes • Observations • an increasing trend in the frequency and duration of North Atlantic hurricane significant at the 99% confidence level (Webster et al., 2005: Science, 309: 1844-1846).

32. Actual (observed) tracks 1979-1988 20 Km Japanese model result of Hurricane tracks (Oouchie et al, 200) Simulated Present day tracks Simulated Future tracks (2080-2099) Greater density

33. Not Enough • Not enough results to make statement about the Caribbean hurricanes • NOAA, 2006: Observed increases can also be explained by natural variability (as opposed to anthropogenic induced variability) • Anthropogenic influence: You are invited to attend Dr. Holland’s lecture tomorrow for more information at 6 pm, Social Science Lecture Theatre

34. Sea Level Rise • Observation • The rise in the Caribbean appears to be near the global mean (Church et al, 2004: J. Clim., 17, 2609-2625). • 1.8 ± 0.3 mm per year or 0.18m per 100year over the period 1950– 2000. • Modelling • Large deviation among models • No regional modelling • Global mean rise expected: 0.2 to 0.5 m up to 2090’s • No enough to make IPCC statement for the Caribbean

35. IPCC AR4 Statement for Caribbean based on limited Peer Reviewed Papers and Data: • Sea levels will likely continue to rise on average during the century • All Caribbean islands are very likely to warm below the global average during this century. • Rainfall in the vicinity of the Greater Antilles is likely to decrease in JJA but changes elsewhere and in DJF are uncertain. • Other non-IPCC projections based on limited data • Frequency and intensity of hurricanes in the North Atlantic will probable increase • Sea level rise in the Caribbean will probable follow global trend

36. Limitations to knowledge of Caribbean Climate Change • Global models do not see islands, except … • Little dynamic and statistical downscaling. • Many Caribbean climatic processes not well understood. • Insufficient model runs to determine regional distribution of cyclone changes. • Uncertainty about future El Niño. • Large deviations among models make regional distribution of sea level rise uncertain. • Limited number of storm surge models.

37. How can we fix the problem? Den Why dem no use TUMS fi get rid of the gas!

38. No quick or easy fixes • Mitigation • Alternative and new sources of energy UWI Physics Students wiring a solar panel Munro Wind turbine

39. No quick or easy fixes • No Mitigation • Point of no return (Runaway Greenhouse effect)?

40. No quick or easy fixes E.G., Study of impact of Climate Change on Biodiversity • Adaptation • Impact studies

41. Need to reduce uncertainties about climate • Much More research needed • To be able to predict day by day weather • To predict future climate change • With others • Tackling Climate Change and Getting ready for 5th IPCC Assessment Climate Studies Group, Mona (CSGM)

42. FINIS What we must do is see the whole world as our “self” Only then will we be worthy of being entrusted with the World (Earth) Only One who values the World as his own body can truly rely on the World in return. Lao Tsu, over 2000 years ago