Key Assertions of and Debates about Global Warming

1. CLIM 101: Weather, Climate and Global Society Key Assertions of and Debates about Global Warming Jagadish Shukla Lecture 16-17: Oct 27-29, 2009

2. Reading for Week 9: Lecture 16-17Key Assertions of and Debates about Global Warming • RG Part 1 and 4

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4. Climate Projections Robust Findings • Even if GHG concentrations where stabilized, climate change would be expected to occur. • The greatest temperature increase will occur at high northern latitudes and over land, with less warming over southern ocean • Precipitation generally increases in the tropical precipitation maxima, decreases in the subtropics, and increases in high latitude. • As the climate warms, snow cover and sea ice extend decrease; glaciers and ice caps loose mass and contribute to sea level rise.

5. Climate Projections Robust Findings • Heat waves become more frequent; frost days are projected to decrease almost everywhere. • Drying of mid-continental areas during summer indicating a great risk of droughts. • Future warming would reduce the capacity of land and ocean to absorb CO2. • Sea level continues to rise in the 21st century and beyonod due to thermal expansion and loss of sea ice.

6. Climate Projections Key Uncertainties • Not possible to predict abrupt change in the meridional overturning circulation in Atlantic. • Model projections of extreme of precipitation has large differences from model to model. • Models show different response of ENSO, blocking and other modes of variability, especially tropical cyclones. • Future’s carbon cycle feedbacks are poorly determined. • Models do not yet exist to predict changes in the Antarctic and Greenland ice sheets. • Climate models show no consistency in regional precipitation changes.

7. An Elegant Science Question: Are increases in greenhouse gases responsible for increase in global mean temperature (global warming)? 14.6 Global Temperature & Carbon Dioxide 1860-2008 395 0.76°C (1.4°F) since 1900 14.4 365 0.55°C (1.0°F) since 1979 14.2 335 14.0 13.8 305 13.6 275 13.4

8. A Puzzle Greenhouse effect and global warming are determined by laws of physics, yet the opinions of the American public are divided along political and ideological lines: Conservatives, Republicans, Some corporations: “Fearmongering Hoax” Liberals, Democrats, Environmentalists: “Real and Present Danger”

9. Science and Politics Percentage of Democrats/Republicans who said that news of global warming was exaggerated (Gallup) Thanks: Ed Maibach, Center for Climate Change Communication (GMU)

10. History of Discussion on Global Warming (1) First Scientific Result: Increases in CO2 will warm Earth’s Climate • Arrhenius • Considered water vapor feedback • Connected global carbon cycle and warming effects of increased CO2 • Estimated 500 years to double CO2

11. History of Discussion on Global Warming (2) 1950: After global temperature rose, 1900 to 1940, The Saturday Evening Post published: Is the World Getting Warmer? (1962 book Silent Spring by Rachel Carson launched the environmental movement)

12. History of Discussion on Global Warming (3) 1970’s -1980’s: Mixed messages b y scientists/media 1972: Sawyer published a paper in Nature, predicting the rise in global means temperature of 0.6ºC in the 20th century. 1973: Newsweek published a report (4/28/1973) on the fear of a forthcoming ice age.

14. History of Discussion on Global Warming (4) 1974: British documentary “Weathermachine” warned about the possibility of ice sheets covering continents in decades. 1975: Broecker published a paper saying we were on the brink of a pronounced global warming 1979-80: Cold war angst; Nuclear warfare leading to nuclear winter

15. History of Discussion on Global Warming (5) 1979: National Academy of Sciences published the Charney report: formal acceptance of global warming due to an increase in CO2 1985: Discovery of Ozone hole (huge confusion with global warming) • Evidence of fragility of Earth’s atmosphere • Satellite pictures of Earth from space had a psychological impact on our perception of Earth’s fragility

16. History of Discussion on Global Warming (6) 1988: On a hot (sizzling) summer day in Washington (severe droughts in the US) a NASA scientist (J. Hansen) testified that he was 99% sure that global arming was upon us. 1988: The New York Times and the Washington Post together published 40 stories on climate change (less than 12 in previous four years). 1988: “Endangered Earth” was named Planet of the year by Time magazine (instead of its usual “Man of the Year”)

17. History of Discussion on Global Warming (7) 1989: IPCC was formed by the nations of the World. (IPCC first report, 1991) 1992: “Earth Summit” in Rio (global warming, one of many environmental issues) 1992: UN Framework Convention on Climate Change (UNFCC) was signed by 166 nations in 1992 (189 by now). Because of the US’s stiff opposition no binding emission reductions.

18. History of Discussion on Global Warming (8) 1997: Kyoto Protocol: the US signed the treaty but did not ratify (not submitted to the US Senate); the US Senate voted 95-0 against any treaty that did not include emission cuts from developing countries also. 2004: The Kyoto Protocol became international law on February 6, 90 days after Russia ratified it (US President George W. Bush withdrew from the Kyoto Protocol).

19. History of Discussion on Global Warming (9) Oil, Coal, Auto Industries and Skeptics Strike Back • Industry lobby groups • Industry supported skeptic scientists • The New York Times and the Washington Post stories on global warming dropped from more than 70 (1989) to less than 20 in 1994 • Skeptics/lobby groups successfully convinced journalists/the public that “global warming was at best an unknown quantity and at worst ideological propaganda … a global fraud” (RG, pp 266)

20. Debate Continues (1) • Washington Post (editorial by James Schlesinger, 2003): “The Science is not settled;” European conspiracy to undermine US economic growth (Schlesinger is on the board of Peabody Energy, the world’s largest coal company) • USA TODAY (13 June, 2005): “The debate’s over: Globe is warming” • TIME (cover, 3 April, 2006): “Be worried. Be very worried.”

21. Debate Continues (2) 2001: “The Skeptical Environmentalist,” book by Bjorn Lomborg (Denmark) (Kyoto Protocol reductions in CO2 emissions will have no effect on temperature; will destroy economies - Republican Congressional leaders invited him to testify) Danish Committee on Scientific Dishonesty labeled the book “objectively dishonest.” (later (2007) he wrote: “Cool it: The Skeptical Environmentalist’s Guide to Global Warming”)

22. Debate Continues (3) • 2005: “State of Fear” by Michael Crichton (fiction to ridicule global warming) • Best seller; (he also co-wrote the screenplay for the movie “Twister” in 1996) • Had private one hour meeting with President George Bush • 2006: Stern Review (UK): major economic impact of global change

23. Movies/Documentaries • “An Inconvenient Truth” (Al Gore) • “The Great Global Warming Swindle” (documentary based on work of Calder and Svensmark, 2007) (Sun, UV, Cosmic Rays)

24. Sun, UV, Cosmic Rays, Low Level Clouds, Warming etc. Sun is producing more sunspots than in the 1800’s More sunspots mean more UV radiation UV helps shield Earth from cosmic rays (more UV, less cosmic rays) Less cosmic rays  less ionization of tiny particles that serve as cloud nuclei  less highly reflective low level cloud formation (more ionization  more cloud nuclei  more clouds) Less clouds  more solar radiation  more warming Hence more sunspot UV means less clouds, more warming This is the idea behind “The Great Global Warming Swindle” No good data on how much cosmic rays have entered or how much change in low level cloud is because of cosmic rays They used discredited data and inaccurate graphs

25. White House • The New York Times (June, 2005): A political appointee in the Bush White House changed: “The Earth is undergoing a period of rapid change,” from “is” to “may be” • He was a staffer with American Petroleum Institute and a lobbyist against the Kyoto Protocol; after the New York Times story he quit the White House and joined Exxon Mobil.

26. Scientists Muzzled • James Hansen of NASA told the New York Times and the BBC in 2006 that he was warned of “dire consequences” if he did not clear from NASA Headquarters any media interviews • Many US scientists (12 Nobel laureates) issued a statement that science was being ignored.

27. The New York TimesIndustry Ignored Its Scientists on Climate “For more than a decade the Global Climate Coalition, a group representing industries with profits tied to fossil fuels, led an aggressive lobbying and public relations campaign against the idea that emissions of heat-trapping gases could lead to global warming.” “But a document filed in a federal lawsuit demonstrates that even as the coalition worked to sway opinion, its own scientific and technical experts were advising that the science backing the role of greenhouse gases in global warming could not be refuted.” By Andrew C. Revkin April 23, 2009

28. Recent Statements “Climate change is the preeminent geopolitical and economic issue of the 21st century. It will increase pressure on water, food and land, reverse years of development gains and exacerbate poverty, destabilize fragile states and topple governments.” Ban Ki-Moon U.N. Secretary General (Washington Post, 9/22/2009) “Some of the prescriptions to address climate change, such as the climate bill passed by the House in June (2009), present more risks to the economy than global warming does.” The Chamber of Commerce and the National Association of Manufacturers (The Washington Post, 9/21/2009)

31. Key Assertions of Global Warming Theory • Global warming is real – the theory has been confirmed. • Future warming will be very large, if we carry on with BAU* • Impacts of the future warming could be very bad. • Changing course requires radical economic changes.

32. Key Assertions of Global Warming Theory 1. Global Warming is Real

34. Key Assertions of Global Warming Theory 1. Global Warming is Real

35. Key Assertions of Global Warming Theory 1. Global Warming is Real (Sresa1b YR 71-100) minus (20c3m 1969-98), Global Average = 2.61

36. Global Warming is unequivocal Since 1970, rise in: Decrease in: • Global surface temperatures NH Snow extent • Tropospheric temperatures Arctic sea ice • Global SSTs, ocean Ts Glaciers • Global sea level Cold temperatures • Water vapor • Rainfall intensity • Precipitation extratropics • Hurricane intensity • Drought • Extreme high temperatures • Heat waves

37. Key Assertions of Global Warming Theory • Global warming is real – the theory has been confirmed. • Future warming will be very large, if we carry on with BAU* • Impacts of the future warming could be very bad. • Changing course requires radical economic changes.

38. Key Assertions of Global Warming Theory 2. Future warming will be very large, if we carry on with BAU Observed and Projected Global Mean Warming

39. Key Assertions of Global Warming Theory 2. Future warming will be very large, if we carry on with BAU Global Mean Sea Level Relative to the 1980 to 1999 mean

40. Key Assertions of Global Warming Theory • Global warming is real – the theory has been confirmed. • Future warming will be very large, if we carry on with BAU* • Impacts of the future warming could be very bad. • Changing course requires radical economic changes.

41. Key Assertions of Global Warming Theory Main threat to a sustainable Earth 3. Impacts of future warming could be very bad.

42. Summary of Major Impacts • Heat waves; Droughts; Forest fires • Coastal area’s habitability (sea level) • Health (cholera; malaria; dengue; lyme) • Biodiversity: extinction of species • Agriculture (uneven); Tropics (serious) • Water (drying; snow melt; glacier melt)

43. Key Assertions of Global Warming Theory • Global warming is real – the theory has been confirmed. • Future warming will be very large, if we carry on with BAU* • Impacts of the future warming could be very bad. • Changing course requires radical economic changes.

44. Key Assertions of Global Warming Theory 4. Changing course requires radical economic changes STERN REVIEW: The Economics of Climate Change • Ignoring climate change will damage economic growth. (The poorest countries and people will suffer earliest and most.) • 2. The damage will be on a scale similar to those associated with the great wars and the economic depression. • 3. It will be difficult or impossible to reverse changes. • 4. The earlier effective action is taken, the less costly it will be.

45. Key Assertions of Global Warming Theory 4. Changing course requires radical economic changes STERN REVIEW: The Economics of Climate Change • Damages from business-as-usual scenario would be at least 5% and up to 20% of Global GDP a year • Costs of removing most of the climate risk are around 1% of GDP per year • This is equivalent to paying on average 1% more for what we buy • “We can grow and be green” Sir Nicholas Stern

46. A Puzzle Greenhouse effect and global warming are determined by laws of physics, yet the opinions of the American public are divided along political and ideological lines: Conservatives, Republicans, Some corporations: “Fearmongering Hoax” Liberals, Democrats, Environmentalists: “Real and Present Danger”

47. Extreme Viewpoints Senator James Inhofe (R, Oklahoma), Former Chair, Senate Environmental and Public Works Committee — “The threat of catastrophic global warming is the greatest hoax ever perpetrated on the American people” U.N. Secretary General Ban Ki-Moon — “Climate change is the defining issue of our age.” Nobel Laureate and Secretary of DOE, Steven Chu — “Science has unambiguously shown that we are altering the destiny of our planet.”

48. “In a worst case scenario, there might - in the twenty-second century - be only a remnant of humanity eking out a diminished existence in the polar regions and the few remaining oases left on a hot and arid Earth.” James Lovelock (Rough Guide, 2006) An Extreme Viewpoint

49. Science and Politics Global Warming’s Six Americas (Summer, 2007) Doubtful/Dismissive  Predominantly Conservatives Alarmed/Concerned  Predominantly Liberals Thanks: Ed Maibach, Center for Climate Change Communication (GMU)

50. http://climatechange.gmu.edu