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The Science of Climate Change

The Science of Climate Change. Where We Are : The Consensus, the Controversy, and the Climate Robert Wyman Partner, Latham & Watkins LLP. The IPCC . The Intergovernmental Panel on Climate Change Established in 1988 to assess scientific basis of climate change

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The Science of Climate Change

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  1. The Science of Climate Change Where We Are: The Consensus, the Controversy, and the Climate Robert Wyman Partner, Latham & Watkins LLP

  2. The IPCC • The Intergovernmental Panel on Climate Change • Established in 1988 to assess scientific basis of climate change • Open to all members of UN and WMO • Intended to be policy-neutral • Most work performed by more than 1000 volunteer scientists • Earned share of Nobel Peace Prize in 2007

  3. Current Structure of IPCC • IPCC Panel comprised of government delegations; sets agenda • IPCC Bureau (31 members) provides guidance to Lead Authors • Since 2001, most work of IPCC performed by 3 Working Groups

  4. How Climate Assessments are Made: • Assessments generated every 4-7 years • Last report in 2007; next one expected in 2014 • Step 1: IPCC evaluates lessons from previous assessments • Step 2: Panel elects IPCC Chair, the Co-Chairs of Working Groups, and the rest of Bureau • Step 3: Working Group Co-Chairs select the Coordinating Lead Authors (CLA’s) and Lead Authors (LA’s) • CLA’s coordinate major sections of Working Group report • LA’s ensure work is based on best evidence and is brought together in a consistent manner

  5. How Climate Assessments are Made: • Step 4: CLA’s and LA’s receive input from Contributing Authors (CA’s) • CA’s prepare technical information for assimilation • Step 5: Reviews of Reports • 2 formal reviews and one or more informal reviews • Informal reviews provided by small number of scientists (usually other authors) • Experts then review first complete draft • LA’s respond to comments, prepare second draft • Review Editors ensure comments and controversial issues are handled appropriately • Second Draft reviewed by same experts, government representatives

  6. How Climate Assessments are Made: • Step 6: Final Working Group Report • Four layers • main chapter texts, executive summaries, technical summaries & • “Summary for Policymakers” • Summary is approved, line by line, in a session chaired by WG Co-Chairs and attended by government representatives • After approval, entire report forwarded to Panel for acceptance • Summaries for policymakers are most important because they have highest visibility • Step 7: The Synthesis Report • Combines findings of all working groups • Only two layers • Main report (divided into 6 topics) and a Summary for Policymakers • Summary is approved line by line

  7. Inherent Obstacles with Study of Climate • Available scientific information: • Is extensive, multinational, and multidisciplinary • Extends across multiple spatial and temporal scales • Subject to different interpretations and a wide range of uncertainties • Climate change is politically charged due to economic consequences • Traditional linear science-for-policy model will not work • Expert Judgment essential

  8. Additional Difficulties for WGII and WGIII • WG I – physical climate analysis based on: • Natural science disciplines • Peer-reviewed literature • Global models and observations • WG II and WG III • Because focused on the effects of and the responses to climate change, analyses based on: • Social science disciplines • Fewer experts • Non-peer reviewed literature (gray literature)

  9. The conclusions of IPCC drive policy decisions at home and abroad • Ex: EPA’s recent “endangerment finding” that greenhouse gases are a danger to public health • Finding based on IPCC conclusions • Endangerment finding sets up regulation of greenhouse gases through the Clean Air Act • Ex: IPCC’s work provided scientific basis for proposed “cap and trade” legislation that recently passed the U.S. House of Representatives

  10. Key Findings of IPCC • Second Assessment Report (1995) • “Climate has changed over the past century” • Global mean surface air temperature has increased between 0.3 and 0.6 degrees C since late 19th century • Global sea level has risen between 10 and 25 cm over the past 100 years; rise may be related to increase in global mean temperature • “The balance of evidence suggests a discernible human influence on global climate”

  11. Key Findings of IPCC • Third Assessment Report (2001) • Temperature increase in 20th century “likely” to have been the largest of any century in past 100 years • “Very likely” that the 1990’s was the warmest decade on record (since 1861) and 1998 was the warmest year • New, stronger evidence that most warming observed over last 50 years attributable to human activities

  12. Key Findings of IPCC • Fourth Assessment Report (AR4) (2007) • Most warming of past 50 years is “very likely” (odds 9 out of 10)due to human increases in greenhouse gases • Consensus: “Warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global average sea level”

  13. Other Scientific Findings: • Observed change is faster than expected • Newer studies foresee greater change impacts • Climate change impacts are already affecting the U.S.

  14. Faster Change: Large Ice Sheets IPCC Third Assessment Report (2001) The Antarctic ice sheet as a whole is likely to increase in mass during the 21st century. IPCC Fourth Assessment Report (2007) …the ice sheets in Greenland and Antarctica have very likely been contributing to sea level rise over 1993 to 2003. Shepherd & Wingham (2007) …data show that Antarctica and Greenland are each losing mass overall. 14

  15. Greater Sea Level Rise 2.6 ft “best estimate” 15 Pew Center Science Brief 2

  16. GCRP Report • Key Findings • Global warming is unequivocal and primarily human-induced • Climate changes are underway in the U.S. and projected to grow • Widespread climate-related impacts are occurring now and are expected to increase This report is“…by far the most up to date, comprehensive, and authoritative assessment of climate change impacts on the United States. It is focused … on what is already happening and … what is expected to happen going forward under both low-emission scenarios where [we] elect to take serious measures to reduce the pace and magnitude of climate change, and under higher-emission scenarios in which we don’t.” John Holdren, President’s Science Advisor GCRP Press Conference, June 2009 16

  17. NORTHWEST • Declining snowpack affects water, hydro • Loss of coldwater fish • Increased wildfires • NORTHEAST • More extreme heat • Declining air quality • Increase in heavy rain • Loss of sugar maple • GREAT PLAINS • Ag stresses from water availability, higher temps • Alterations of habitat • MIDWEST • More heat waves • Ag stresses from floods, droughts, pests • SOUTHWEST • Scarce water supplies • Incr. drought, wildfires, invasive species • SOUTHEAST • SLR and incr. hurricane intensity • Droughts, reduced water avail. • Heat stress, extreme weather • ALASKA • Hotter, drier summers • Loss of sea ice • Thawing permafrost damages infrastructure 17

  18. Extreme Heat US GCRP Climate Impacts Report 18

  19. Climate on the Move US GCRP Climate Impacts Report 19

  20. Climate on the Move Projected Heat Related Deaths in Chicago US GCRP Climate Impacts Report 20

  21. What a rise in sea level of 3.3 feet means for the Mid-Atlantic region 21

  22. The Bottom Line . . . “I think that much of the foot dragging in addressing climate change is a reflection of the perception that climate change is way down the road … and that it only affects remote parts of the planet. And this report demonstrates … that climate change is happening now and it's happening in our own backyards and it affects the kinds of things people care about.” Dr. Jane Lubchenco, NOAA Administrator GCRP Press Conference, June 2009 22

  23. Or is it . . . • The Recent Controversies • East Anglia CRU e-mail scandal • IPCC admits errors in the 2007 assessment • Independent Reviews • U.K. Investigation of CRU e-mails (July 2010) • U.S. Senate Committee on Environment and Public Works: Minority Staff Report on CRU e-mails (Feb 2010) • InterAcademy Council (IPCC review) (August 2010) • Netherlands Environmental Assessment Agency (IPCC review) (July 2010)

  24. The East Anglia Controversy • The Climate Research Unit, University of East Anglia • CRU is a small research unit which, over the last 30 years, has played an important role in climate science • In November 2009, approximately 1000 e-mails from CRU scientists were hacked • E-mails raise question of scientists’ integrity

  25. Why is the important? • A number of CRU scientists played important roles in generating IPCC reports • Important to remember that the CRU is not the IPCC; it is just a small unit that contributes to IPCC findings In case you are falling asleep, This chart is a joke . . . This is not CRU’s scientific method … But some opponents claim it is

  26. Roles of CRU Scientists in IPCC Reports

  27. A sampling of the CRU allegations • Is the famous Hockey Stick chart a product of cooked science? • Hockey Stick – charts temperatures over last 1000 years

  28. Hockey Stick Controversy • The “Divergence Problem” • No thermometers pre-1850 • So, use a proxy. For example, use tree ring density to chart temperatures • Hockey Stick Chart based on four such proxies • One created by Briffa (tree ring), one by Jones, and two by Mann • Next chart shows all reconstructions – from IPCC 3rd AR (2001)

  29. Hockey Stick Controversy Where did the green line go?

  30. Hockey Stick Controversy • The green line declines around 1960 • Chart below shows original unpublished data Tree ring model shows a temperature decline after 1960 – Is the earth unequivocally warming? Also note the black lines – they represent measured temperature. They begin around 1850 Red proxy line also declines a bit … then goes back up

  31. Hockey Stick Controversy What to Do? • Green line decline sends Briffa, Jones, and Mann into a frenzy • Scientists are concerned that the green line decline will contradict the idea of unprecedented warming • Briffa responds in an e-mail From: Keith Briffa [CRU] To: Chris Folland [UK Met Office]; Phil Jones [CRU]; Michael E. Mann [University of Virginia] Cc: Tom Karl [National Climatic Data Center – NOAA] September 22, 1999 Subject: RE: IPCC revisions . . . I know there is pressure to present a nice tidy story as regards 'apparent unprecedented warming in a thousand years or more in the proxy data’ but in reality the situation is not quite so simple. We don't have a lot of proxies that come right up to date and those that do (at least a significant number of tree proxies ) some unexpected changes in response that do not match the recent warming. . . .

  32. “Hide the Decline” From: Phil Jones [CRU] To: Ray Bradley [University of Massachusetts, Amherst]; Michael E. Mann [University of Virginia]; Malcolm Hughes [University of Arizona] Cc: Keith Briffa [CRU]; Tom Osborn [CRU]52 November 16, 1999 Subject: Diagram for WMO [World Meteorological Organization] Statement Dear Ray, Mike and Malcolm, Once Tim's got a diagram here we'll send that either later today or first thing tomorrow. I’ve just completed Mike’s Nature trick of adding in the real temps to each series for the last 20 years (ie from 1981 onwards) and from 1961 for Keith’s to hide the decline. Mike's series got the annual land and marine values while the other two got April-Sept for NH [Northern Hemisphere] land N of 20N. The latter two are real for 1999, while the estimate for 1999 for NH combined is +0.44C wrt 61-90. The Global estimate for 1999 with data through Oct is +0.35C cf. 0.57 for 1998. Thanks for the comments, Ray. Cheers Phil

  33. “Hide the Decline” • Cut off tree ring data where it begins downward trend (around 1961) • And merge line with recorded temperatures • “Any scientist ought to know that you just can’t mix and match proxy and actual data. They’re apples and oranges.” • Phillip Scott; emeritus professor of biogeography at London’s School of Oriental and African Studies Decline Hidden

  34. Fallout • Remember, the “hide the decline” trick was performed on the 2001 IPCC report, not the 2007 report • UK assesses the controversy • Determines that similar information concerning tree ring proxies presented in 4th report was not misleading • But the information provided in the “iconic” graph of the 3rd report was misleading. • Chart did not adequately explain methods • Overall, this error does not “undermine the conclusions” of the IPCC—that climate change is happening and is probably caused by humans

  35. Other criticisms • In addition to “hide the decline,” UK assessors determined that the e-mails revealed that: • Scientists demonstrated a “consistent pattern of failing to display the proper degree of openness” • CRU researchers’ responses for requests of information were “unhelpful and defensive”

  36. Other Views • The Senate Minority Staff on the EPW Committee was more harsh in its assessment • Determined the scientists tried to undermine peer review • Were actively pursuing an agenda • Does this mean climate change is a hoax?

  37. The Debate

  38. Next Controversy:IPCC Admits Errors on 4th AR • Reported errors are largely unrelated to the CRU e-mail controversy • Jan 20, 2010 announces error: • AR 4 asserted: “Glaciers in the Himalayas are receding faster than in any part of the world . . . the likelihood of them disappearing by the year 2035 and perhaps sooner is very high.” • IPCC official admits error. “It is so wrong it is not even worth discussing”

  39. Another Error • In February 2010 IPCC admits another error in their 4th AR • Report asserted that 55% of Netherlands was currently below sea level. Report traced this figure to global warming. • IPCC later correct assertion: • Only 26% of the country was below sea level, • 55% is at risk of flooding

  40. Errors Prompt Independent Review of IPCC Procedures • Review by Netherlands Environmental Assessment Agency • Findings: • Only one other major error in AR 4 • Report projected a 50 to 60% decrease in productivity of anchovy fisheries on African West Coast • The report should have read that there appeared to be a 50 to 60% decrease in extreme wind and seawater turbulence, which may lead to some unquantified negative effects on anchovy population

  41. Other Dutch Findings • Summary conclusions presented in the “Summaries for Policymakers” were well founded and did not contain significant errors • But some minor inaccuracies in summary conclusions, and • Seven of the 32 summary conclusions on the regional impacts of global warming contain information that could not be sufficiently traced to the underlying source within the Working Group II report

  42. More findings • In the “Summaries for Policymakers,” the WGII assessments single out negative effects of warming • This “risk oriented approach” of focusing on the negative not sufficiently disclosed in the report • Report also highlights risks at upper end of uncertainty range • Does not put information in context • As a result, policymakers often are not aware of potential benefits of warming • Benefits often buried in technical layers of report • Ex: Synthesis Report contains discussion on crop yields that are likely to be reduced in Africa, but does not mention crop yields that may increase due to global warming

  43. Report Recommendations and Conclusions • Dutch findings do not contradict main conclusion of IPCC on impact, adaption, and vulnerability related to climate change (WG II) • Findings do not contradict IPCC conclusion that: • Global warming is unequivocal and • “Very Likely” caused by human activity • But room for improvement – recommendations: • Provide public website for submission of errors found in published reports • Provide stronger underpinnings for generalizations • Strengthen review process • More disclosure of methodology

  44. InterAcademy Council • Multinational organization of science academies • Similar findings and recommendations: • Assessment reports successful overall • But IPCC must structurally reform • Needs more day-to-day leadership (Executive Director needed) • Needs to ensure controversies adequately addressed • More targeted review process to focus on specific problems • Quantify uncertainty where possible (likelihood scale should be used where appropriate) • Authors need to indicate scientific basis for assigning a probability that an event will occur • Greater emphasis on transparency

  45. Most Recent Developments • 2010 on track to be a record hot year (running neck and neck with 1998, the hottest year on record) • Recently discovered that the Greenland and West Antarctic Ice Caps are melting at half the speed previously predicted

  46. In the end . . . • Climate Change • Is it happening? • Is it caused by man? • Even if it is happening, can we counter it? • Should we counter it, or should we adapt? • You decide

  47. Special Thanks • A number of the slides in this presentation were created by the Pew Center on Global Climate Change

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