EPA’s Response to the Petitions 

to Reconsider the Endangerment 

and Cause or Contribute 

Findings for Greenhouse Gases 

under Section 202(a) of the Clean 

Air Act 

Volume 2: Issues Raised by 

Petitioners on EPA’s Use of IPCC

U.S. Environmental Protection Agency 

Office of Atmospheric Programs 

Climate Change Division 

Washington, D.C.

1 

TABLE OF CONTENTS 

Page

2.0 Issues Raised by Petitioners on EPA’s Use of IPCC.................................................................6 

2.1 Claims That IPCC Errors Undermine IPCC Findings and Technical Support for 

Endangerment ........................................................................................................................6 

2.1.1 Overview....................................................................................................................6 

2.1.2 Accuracy of Statement on Percent of the Netherlands Below Sea Level..................8 

2.1.3 Validity of Himalayan Glacier Projection .................................................................9 

2.1.4 Characterization of Climate Change and Disaster Losses .......................................12 

2.1.5 Validity of Alps, Andes, and African Mountain Snow Impacts..............................20 

2.1.6 Validity of Amazon Rainforest Dieback Projection ................................................21 

2.1.7 Validity of African Rain-Fed Agriculture Projection ..............................................23 

2.1.8 Summary..................................................................................................................33 

2.2 Claims That the IPCC Has a Policy Agenda and Is Not Objective and Impartial...............34 

2.2.1 Overview..................................................................................................................34 

2.2.2 Background..............................................................................................................34 

2.2.3 Responses to Arguably New Objections Raised by the Petitioners.........................39 

2.2.3.1 Allegations of Inappropriate Authorship and Reviewer Roles Among 

IPCC Personnel ...............................................................................................39 

2.2.3.2 Allegations That Citing One’s Own Papers Compromises Objectivity...........46 

2.2.3.3 Allegations That IPCC Is Biased .....................................................................48 

2.2.3.4 Allegations That IPCC Lead Authors Forced Consensus and Suppressed 

Dissenting Views..............................................................................................57 

2.2.4 Responses to Allegations Based on Information That Is Not New .........................65 

2.2.4.1 Allegations of Inappropriate Collaborations Among IPCC Authors ..............65 

2.2.4.2 Allegations Regarding Insufficient Peer Review Processes for the IPCC.......67 

2.2.4.3 Allegations That IPCC Authors Manipulated Deadlines for New 

Literature .........................................................................................................68 

2.2.4.4 Allegations Regarding the IPCC’s Use of Gray Literature.............................71 

2.2.5 Summary..................................................................................................................73 

References..............................................................................................................................................75 

3 
ACRONYMS 

°C degrees Celsius 

°F degrees Fahrenheit 

AIRS Atmospheric Infrared Sounder 

AMS American Meteorological Society 

AOGCM Atmosphere-Ocean General Circulation Models 

AR4 IPCC Fourth Assessment Report 

BOM Australian Bureau of Meteorology 

CH4 methane 

cm centimeter 

CCSP U.S. Climate Change Science Program 

CDIAC Carbon Dioxide Information Analysis Center 

CMIP Coupled Model Intercomparison Project 

CO2 carbon dioxide 

CRU Climatic Research Unit 

EPA U.S. Environmental Protection Agency 

FOIA Freedom of Information Act 

GHCN Global Historical Climatology Network 

GHG greenhouse gases 

GISS Goddard Institute for Space Studies (NASA) 

GSL Global Snow Laboratory (Rutgers University) 

IAC InterAcademy Council 

IEA Institute of Economic Analysis 

IISD International Institute for Sustainable Development 

IJC International Journal of Climatology 

IPCC Intergovernmental Panel on Climate Change 

IQA Information Quality Act 

LIA Little Ice Age 

MET United Kingdom Meteorological Office 

MWP Medieval Warm Period 

NASA National Aeronautics and Space Administration 

NCAR National Center for Atmospheric Research 

NCDC National Climatic Data Center 

NIWA National Institute of Water & Atmospheric Research 

NMS National Meteorological Station 

NOAA National Oceanic and Atmospheric Administration 

NRC National Research Council 

NSIDC U.S. National and Snow and Ice Data Center 

ORNL Oak Ridge National Laboratory 

PBL Netherlands Environmental Assessment Agency 

RMS Risk Management Solutions 

RTC Response to Comments 

RTP Response to Petitions 

SAB Scientific Advisory Board 

SALR saturated adiabatic lapse rate 

TSD Technical Support Document 

4 
UAH University of Alabama–Huntsville 

UCAR University Corporation for Atmospheric Research 

UHI urban heat island 

UK United Kingdom 

USGCRP U.S. Global Change Research Program 

USHCN United States Historical Climatology Network 

W/m2 watts per meter squared 

WMO World Meteorological Organization 

WWR World Weather Reports 

5 
2.0 Issues Raised by Petitioners on EPA’s Use of IPCC 

2.1 Claims That IPCC Errors Undermine IPCC Findings and Technical Support for 

Endangerment 

2.1.1 Overview 

Several petitioners (Peabody Energy, the State of Texas, the Coalition for Responsible 

Regulation, the Competitive Enterprise Institute, the Ohio Coal Association, and the 

Southeastern Legal Foundation) contend that alleged errors and/or unsupported findings in IPCC 

reports demonstrate that the science on which the Administrator relied for the Endangerment 

Finding is uncertain and/or not credible. We have examined each specific instance of error, 

alleged error, and/or alleged unsupported statement in the voluminous IPCC report and we find 

that the evidence cited by petitioners does not support this conclusion. 

In reviewing the information provided by petitioners, EPA has determined that most—if not 

all—of the alleged errors and/or unsupported statements highlighted by petitioners are not 

relevant, not truly erroneous or unsupported, and/or inconsequential to the Administrator’s 

Finding. In many cases, the petitioners’ interpretation of both the alleged error (or alleged 

unsupported statement) and its implications is not supported by the evidence provided. Clearly, 

the charge that there are or might be errors or unsupported statements in the IPCC’s Fourth 

Assessment Report (AR4) is serious, and we agree with petitioners that such claims merit 

thorough review. EPA has done such a review; we find that the documented errors in the AR4 

are not significant, and do not call into question the fundamental and broad evidence on which 

the Endangerment Finding rests. Moreover, the occurrence of the few documented errors in a 

study the size of the IPCC report is not unexpected and does not call into question the credibility 

of the entire report and all of its findings. 

The Netherlands Environmental Assessment Agency (PBL) conducted its own independent 

assessment of the regional chapters (9 through 16) in Working Group II’s contribution to the 

AR4, where many of the errors, alleged errors, and/or alleged unsupported statements have been 

identified. The report Assessing an IPCC Assessment (PBL, 2010a) finds “no significant errors” 

in summary conclusions, though it notes that “provenance of summary statements needs to 

become more transparent in future reports.” 

PBL (2010a) also states that “examples of negative impacts dominate at summary level,” 

indicating that the IPCC selected a “risk-oriented” approach in communicating to policymakers. 

The report states: 

The PBL subscribes to the importance of an approach that highlights what may go wrong 

under unmitigated climate change, but Working Group II Report lacked a clear 

explanation of the choice of approach and its consequences. Alternatively, it could be 

argued that policymakers should be presented with a complete picture in the Summary 

for Policymakers, not just with negative examples (without suggesting that potential 

positive effects cancel out potential effects). 

6 
While we cited the IPCC Working Group II Summary for Policymakers in the Endangerment 

Technical Support Document (TSD), we relied most heavily on information from the full 

chapters in the Working Group II report, specifically Chapter 14 on North America, as well as 

other assessment literature such as the U.S. Global Change Research Program (USGCRP) 

assessment Global Climate Change Impacts in the United States (Karl et al., 2009). The 

Administrator considered both the positive and negative effects of climate change, as the 

Endangerment Finding states (Section I.A.): 

The Administrator is using her judgment, based on existing science, to weigh the threat 

for each of the identifiable risks, to weigh the potential benefits where relevant, and 

ultimately to assess whether these risks and effects, when viewed in total, endanger 

public health or welfare. 

In addition, the Administrator found endangerment based on impacts in the United States alone, 

with international impacts providing some supporting information, as the Endangerment Finding 

states (Section III.D): 

EPA is not considering international effects to determine whether the health and welfare 

of the public in a foreign country is endangered. Instead, EPA’s consideration of 

international effects for purposes of determining endangerment is limited to how those 

international effects impact the health and welfare of the U.S. population. 

The Administrator looked first at impacts in the United States itself, and determined that 

these impacts are reasonably anticipated to endanger the public health and the welfare of 

the U.S. population. That remains the Administrator’s position, and by itself supports her 

determination of endangerment. 

Despite its few criticisms of the IPCC, PBL (2010a) concludes: 

Our findings do not contradict the main conclusions of the IPCC on impacts, adaptation 

and vulnerability related to climate change. There is ample observation evidence of 

natural systems being influenced by climate change on regional levels. The negative 

impacts under unmitigated climate change pose substantial risks to most parts of the 

world, with risks increasing at higher global average temperatures. 

This conclusion is very consistent with the conclusion the Administrator reached in the 

Endangerment Finding, after weighing the balance of evidence. 

This section responds to the major arguments of the petitioners on the significance of alleged 

errors and/or unsupported statements in the IPCC reports, and assesses the implications of these 

errors and/or unsupported statements for the credibility and reliability of the major findings and 

conclusions of the IPCC and other assessment literature. 

7 
2.1.2 Accuracy of Statement on Percent of the Netherlands Below Sea Level 

Comment (2-1): 

Peabody Energy and the State of Texas contend that the IPCC erroneously stated (in Working 

Group II’s contribution to the AR4) that 55% of the Netherlands is below sea level, whereas the 

actual number is much lower according to Dutch materials (26%). 

Response (2-1): 

The statistic quoted in the IPCC AR4 is inaccurate. When this error was identified, PBL (2010b) 

published a correction: 

In the 2007 IPCC report by the Working Group 2 (Climate change 2007: Impacts, 

Adaptation and Vulnerability) a mistake has entered the text that was supplied by the 

Netherlands Environmental Assessment Agency, regarding the risks of flooding for the 

Netherlands. In the chapter on Europe, on page 547, it says that 55 per cent of the 

Netherlands is below sea level (‘The Netherlands is an example of a country highly 

susceptible to both sea level rise and river flooding because 55% of its territory is below 

sea level’). This should have read that 55 per cent of the Netherlands is at risk of 

flooding; 26 per cent of the country is below sea level, and 29 per cent is susceptible to 

river flooding. Examples of the latter are the near floodings, in the mid-1990s, of areas 

along the rivers Meuse and Waal – areas that are well above sea level. 

The IPCC agrees that this statistic is incorrect in the AR4, and also notes that the same mistake 

was made by other reputable groups (Reuters, 2010). For example, the IPCC—in a written 

statement provided to Reuters—indicated that a report from the Dutch Ministry of Transport had 

stated “‘about 60%’ of the country is below sea level,” and referred to a European Commission 

study saying “about half” (Reuters, 2010). As noted by the IPCC statement, the error was not 

made by authors of the AR4, but originated with PBL, which supplied the text. To correct the 

mistake, the IPCC published an official erratum (IPCC, 2010d): 

2) Page 547. Section 12.2.3. Line 20: Delete “below sea level” and replace with “at risk 

flooding”. 

The IPCC was further quoted as saying (Reuters, 2010): “The sea level statistic was used for 

background information only, and the updated information remains consistent with the overall 

conclusions.” 

In its independent report Assessing an IPCC Assessment (PBL, 2010a), PBL, which was 

responsible for the error, states: 

We acknowledge that this error was not the fault of the IPCC (Coordinating) Lead 

Authors or Co-Chairs. The error was made by a Contributing Author from the PBL, and 

the (Coordinating) Lead Authors [of the IPCC] are not to blame for relying on Dutch 

information provided by a Dutch agency. 

8 
EPA concludes that this error is minor and inconsequential to the Administrator’s Endangerment 

Finding. EPA does not refer to or rely on this statistic in the Endangerment Finding or 

supporting documents, and this information does not pertain to endangerment of public health 

and welfare in the United States in any meaningful way. It does not call into question the 

integrity of the IPCC, and it has no impact on the scientific support for EPA’s Endangerment 

Finding. Furthermore, as the error pertains to a statistic outside the United States, it is not 

relevant to the Endangerment Finding. As noted in Subsection 2.1.1, the Endangerment Finding 

states (Section III.D): “The Administrator looked first at impacts in the United States itself, and 

determined that these impacts are reasonably anticipated to endanger the public health and the 

welfare of the U.S. population. That remains the Administrator’s position, and by itself supports 

her determination of endangerment.” 

2.1.3 Validity of Himalayan Glacier Projection 

Comment (2-2): 

Several petitioners (the Coalition for Responsible Regulation, the Competitive Enterprise 

Institute, the Ohio Coal Association, Peabody Energy, the Southeastern Legal Foundation, and 

the State of Texas) state that the IPCC erred in including a projection that glaciers in the 

Himalayas would disappear by 2035, and they claim EPA relied on this projection in the 

Endangerment Finding. Petitioners argue that this error undermines the credibility of the IPCC 

reports. The Ohio Coal Association writes: “The Agency no longer has a basis for unquestioned 

confidence that the IPCC reports present a fair, unbiased, and accurate assessment of climate 

science.” Peabody states the error: “...undercuts EPA’s conclusion that the IPCC review process 

was ‘rigorous’ and shows how reliance on the IPCC led to errors in EPA’s Endangerment 

Finding.” 

Response (2-2): 

The IPCC has issued a correction pertaining to this projection for the melting of Himalayan 

glaciers (IPCC, 2010f): 

The Synthesis Report, the concluding document of the Fourth Assessment Report of the 

Intergovernmental Panel on Climate Change (page 49) stated: “Climate change is 

expected to exacerbate current stresses on water resources from population growth and 

economic and land-use change, including urbanization. On a regional scale, mountain 

snow pack, glaciers and small ice caps play a crucial role in freshwater availability. 

Widespread mass losses from glaciers and reductions in snow cover over recent decades 

are projected to accelerate throughout the 21st century, reducing water availability, 

hydropower potential, and changing seasonality of flows in regions supplied by 

meltwater from major mountain ranges (e.g. Hindu-Kush, Himalaya, Andes), where more 

than one-sixth of the world population currently lives.” 

This conclusion is robust, appropriate, and entirely consistent with the underlying science 

and the broader IPCC assessment. It has, however, recently come to our attention that a 

paragraph in the 938-page Working Group II contribution to the underlying assessment 

refers to poorly substantiated estimates of rate of recession and date for the disappearance 

of Himalayan glaciers. In drafting the paragraph in question, the clear and well9 
established standards of evidence, required by the IPCC procedures, were not applied 

properly. 

The Chair, Vice-Chairs, and Co-chairs of the IPCC regret the poor application of wellestablished IPCC procedures in this instance. This episode demonstrates that the quality 

of the assessment depends on absolute adherence to the IPCC standards, including 

thorough review of “the quality and validity of each source before incorporating results 

from the source into an IPCC Report”. We reaffirm our strong commitment to ensuring 

this level of performance. 

First, as described in Response 2-3 below, this error concerns a single study, out of many that 

support the IPCC’s conclusions regarding glacier recession. Second, EPA does not refer to this 

projection in the Endangerment Finding or supporting material. We acknowledge that the TSD 

mentions Himalayan glaciers; Table 16.1 of Section 16(b) (“Overview of International 

Impacts”), highlighting “examples” of international impacts, states (U.S. EPA, 2009): 

Glacier melt in the Himalayas is projected to increase flooding and rock avalanches from 

destabilized slopes and to affect water resources within the next two to three decades. 

This will be followed by decreased river flows as the glaciers recede. 

This statement is entirely consistent with the IPCC’s statement in its Synthesis Report (on page 

49) (IPCC, 2007b), cited above, which the IPCC notes is “robust, appropriate, and entirely 

consistent with the underlying science and the broader IPCC assessment.” EPA did not refer to a 

rate of recession or a timeframe in which the Himalayan glaciers would be gone. 

This error represents one lapse in the deliberate preparation and review of a multi-volume 

assessment containing thousands of pages of findings and conclusions. Despite petitioners’ 

claims to the contrary, the timing of glacier recession in the Himalayas has no impact on the 

scientific support for EPA’s Endangerment Finding. As noted in Section 2.1.1, the 

Endangerment Finding states (Section III.D): 

The Administrator looked first at impacts in the United States itself, and determined that 

these impacts are reasonably anticipated to endanger the public health and the welfare of 

the U.S. population. That remains the Administrator’s position, and by itself supports her 

determination of endangerment. 

After careful review, the facts do not substantiate the petitioners’ assertion that this error 

undercuts EPA’s conclusion that the IPCC review process was ‘rigorous’ or that reliance on the 

IPCC, among other assessments, led to errors in EPA’s Endangerment Finding.

Comment (2-3): 

The Southeastern Legal Foundation questions the IPCC claim that the conclusions regarding 

Himalayan glaciers presented in the AR4 Synthesis Report are “robust, appropriate, and entirely 

consistent with the underlying science and the broader IPCC assessment” despite the erroneous 

projection. The Southeastern Legal Foundation states: “The IPCC has now grudgingly retracted 

10 
the claim of imminent Himalayan glacier melt, though it claims the overall conclusions regarding 

glacial melt are robust. How their conclusions can be fake but accurate is not evident.” 

Response (2-3): 

Southeastern Legal Foundation is referring to the following conclusions in the IPCC’s 2007 

Synthesis Report (IPCC, 2007b, page 49): 

Climate change is expected to exacerbate current stresses on water resources from 

population growth and economic and land-use change, including urbanization. On a 

regional scale, mountain snow pack, glaciers and small ice caps play a crucial role in 

freshwater availability. Widespread mass losses from glaciers and reductions in snow 

cover over recent decades are projected to accelerate throughout the 21st century, 

reducing water availability, hydropower potential, and changing seasonality of flows in 

regions supplied by meltwater from major mountain ranges (e.g. Hindu-Kush, Himalaya, 

Andes), where more than one-sixth of the world population currently lives. 

EPA has reviewed the complete discussion of this issue in the AR4, in the Synthesis Report, and 

in the contributions of Working Groups I (IPCC, 2007e) and II (IPCC, 2007g). The IPCC cites 

numerous studies that document Himalaya and other Asian glacier trends, projections, and 

impacts. For example, it references the following findings from a range of studies supporting its 

conclusion: 

 Glaciers in the Asian high mountains have generally shrunk at varying rates (from Su and 

Shi, 2002; Ren et al., 2004; Solomina et al., 2004; Dyurgerov and Meier, 2005)—in IPCC 

Working Group I Chapter 4 (Lemke et al., 2007). 

 The entire Hindu-Kush-Himalaya ice mass has decreased in the last two decades. Water 

supply in areas fed by glacial meltwater from the Hindu Kush and Himalayas, on which 

hundreds of millions of people in China and India depend, will be negatively affected 

(Barnett et al., 2005)—in IPCC Working Group II Chapter 3 (Kundzewicz et al., 2007). 

 The Himalayan glacier Gangotri receded at an average rate of 7.3 meters every year from 

1842 to 1935; from 1985 to 2001, it receded at a rate of 23 meters per year (Hasnain, 

2002)—in IPCC Working Group II Chapter 10 (Cruz et al., 2007). 

 Reductions in the mass of a sample of Northern Hemisphere glaciers (including several in 

Asia) of up to 60% are projected by 2050 (Schneeburger et al., 2003)—in IPCC Working 

Group II Chapter 3 (Kundzewicz et al., 2007). 

 Rapid melting of glaciers can lead to flooding of rivers and the formation of glacial meltwater lakes, which may pose a serious risk of outburst floods (Coudrain et al., 2005)—in 

IPCC Working Group II Chapter 3 (Kundzewicz et al., 2007). 

Thus, EPA finds that the single faulty projection highlighted by petitioners does not compromise 

the IPCC’s overall assessment of observed glacier loss, projected glacier loss, and the impacts of 

glacier loss on water resources in the Himalayas. Numerous studies document a general decline 

in Himalayan glacier mass, project substantial future declines, and discuss the impacts of these 

11 
changes on water resources and society, which is consistent with the conclusions drawn by the 

IPCC. The petitioner’s claim implies that the IPCC conclusion in the Synthesis Report depends 

upon a single study, without which we are uncertain as to the fate and timing of Himalayan 

glacier melt. The full discussion of this issue by the IPCC clearly demonstrates that the 

petitioners’ argument is flawed and that the IPCC’s conclusions are well-supported by the 

scientific literature. 

2.1.4 Characterization of Climate Change and Disaster Losses 

Comment (2-4): 

Some petitioners raise concerns with certain aspects of the IPCC’s treatment of climate change 

and natural disasters. The Southeastern Legal Foundation asserts that the IPCC mischaracterized 

the findings of a non-peer-reviewed study (Muir-Wood et al., 2006) on climate change and 

disaster losses. It states that the IPCC reported that global warming was causing an increase in 

losses from weather disasters of 2% per year, even after controlling for economic growth, citing 

the Muir-Wood study even though that study had actually found no trend. Along with the 

Southeastern Legal Foundation, the Competitive Enterprise Institute refers to an article in the 

Sunday Times (Leake, 2010b) indicating that the IPCC wrongly linked climate change to natural 

disasters. Southeastern Legal Foundation finds: 

The EPA Endangerment Finding relies heavily on the assertion that AGW [anthropogenic 

global warming] will cause extreme weather events to become more frequent and more 

severe and thus constitute a danger to human health and welfare—an essential element of 

the Finding. To support this assertion the Finding in turn relies heavily on the IPCC’s 

reports on weather disasters. 

Response (2-4): 

To support the Endangerment Finding, EPA cited the potential impacts of climate change on the 

number and/or severity of certain extreme weather events, for which the Southeastern Legal 

Foundation levels no specific criticism. The TSD did not discuss the link between climate 

change and the historical trends in the economic magnitude of disaster losses. In responding to 

public comments on the issue (e.g., see Responses 7-5 and 7-38 in the Response to Comments 

[RTC] document), EPA acknowledged that many factors influence the economic losses caused 

by disasters which make it difficult to use historical data on trends in economic disaster loss to 

determine the impact of climate change on the losses from weather events in the past. Further, 

the Endangerment Finding is clear that the Administrator’s decision was based on the physical 

and environmental impacts associated with climate change, and how they can affect the 

characteristics of weather events, not the link between climate change and disaster losses. As the 

Endangerment Finding states (Section I.A): 

The evidence concerning how human induced climate change may alter extreme weather 

events also clearly supports a finding of endangerment, given the serious adverse impacts 

that can result from such events and the increase in risk, even if small, of the occurrence 

and intensity of events such as hurricanes and floods. 

12 
With respect to the Muir-Wood study, we neither cited nor relied upon it in our discussion of 

extreme events. In fact, our only specific reference to this study in the record for the 

Endangerment Finding is in Response 1-15 in the RTC documents, which addressed criticism of 

the IPCC’s use of gray literature. The technical aspects of this study were not discussed because 

EPA did not focus on the relationship between climate change and the economic magnitude of 

disaster losses as underlying support for the Endangerment Finding. We note that the TSD did 

include a figure (TSD Figure 14.1) showing information on several factors, including one portion 

(panel e) on observed U.S. hurricane economic damages compared to a measure of Atlantic 

hurricane intensity. This figure was taken from the chapter on North America from Working 

Group II’s contribution to the AR4 (Field et al., 2007, Figure 14.1); the TSD provides no 

commentary on the hurricane economic damages portion (panel e). 

The controversy surrounding the relationship between climate change and economic losses from 

disasters did arise in public comments (e.g., see comments 7-5 and 7-38 in the RTC document), 

to which EPA provided measured, balanced responses consistent with the assessment literature. 

In comment 7-38, for example, the commenter argued that increasing raw damage totals 

associated with tropical storm (or hurricane) damage in coastal communities are not the result of 

climate change, but rather are caused by changes in coastal population, the wealth of the 

population, inflation, and poor sediment management practices. EPA responded: 

EPA agrees that the interaction of a series of drivers adversely impacts coastal areas and 

can contribute to tropical storm damage totals. These drivers include changes in coastal 

population, wealth of the population, inflation, and sediment management practices. 

EPA’s response then focused on the physical impacts of climate change that suggest increased 

risk to the public from severe weather events, pointing to the following findings from the 

assessment literature: 

 Superimposed on accelerated sea level rise, the present storm and wave 

climatology and storm surge frequency distributions suggest more severe coastal 

flooding and erosion hazards (Nicholls et al., 2007). 

 Higher sea level provides an elevated base for storm surges to build upon and 

diminishes the rate at which low-lying areas drain, thereby increasing the risk of 

flooding from rainstorms (CCSP, 2009a). 

 Apart from nonclimatic events such as tsunamis, extreme sea levels occur mainly 

in the form of storm surges generated by tropical or extra-tropical cyclones. 

There is evidence for an increase in extreme high sea level since 1975 based upon 

an analysis of 99th percentiles of hourly sea level at 141 stations over the globe 

(Bindoff et al., 2007). 

We also noted: “USGCRP concludes that future increases in losses will be attributable to 

climate change with high confidence as climate change increases the frequency and intensity of 

many types of extreme weather (Karl et al., 2009).” EPA agrees with this conclusion regarding 

losses in the future—if climate change causes an increase in the frequency or intensity of certain 

severe weather events, then it follows that climate change could lead to increased losses 

compared with what would occur without the increase in those severe weather events. However, 

13 
EPA did not focus on historical trends in the magnitude of economic disaster losses to evaluate 

the likelihood that climate change would lead to an increase in the number or frequency of such 

weather events. For that reason, the charge that the IPCC mischaracterized reports on the 

implications of such historical trends does not materially affect the basis for EPA’s 

Endangerment Finding. 

For its part, the IPCC responded to the allegation that it mischaracterized the Muir-Wood study 

on climate change and disaster losses with an official statement (IPCC, 2010e). The IPCC 

stated, among other things, that the Sunday Times article cited by Southeastern Legal Foundation 

and the Competitive Enterprise Institute: 

Incorrectly assumes that a brief section on trends in economic losses from climate-related 

disasters is everything the IPCC Fourth Assessment Report (2007) has to say about 

changes in extremes and disasters. In fact, the Fourth Assessment Report reaches many 

important conclusions, at many locations in the report, about the role of climate change in 

extreme events. The assessment addresses both observations of past changes and 

projections of future changes in sectors ranging from heat waves and precipitation to 

wildfires. Each of these is a careful assessment of the available evidence, with a 

thorough consideration of the confidence with which each conclusion can be drawn. 

To summarize, petitioners do not properly characterize the information on which EPA relied in 

making the Endangerment Finding. Petitioners also mischaracterize the statements of the IPCC. 

The IPCC reasonably characterized the links between climate change and the projected increase 

in frequency and severity of severe weather events. The IPCC discussed the various types of 

evidence supporting this view, which include but are clearly not limited to consideration of the 

evidence for and against the ability to identify a climate change impact from the trend in 

economic magnitude of disaster losses, and the IPCC caveated its discussion of this issue. To 

support the Endangerment Finding, EPA cited the physical and environmental factors indicating 

that climate change would lead to an increase in frequency and severity of certain severe weather 

events. Only in response to public comments did EPA discuss what can be determined from 

analyses of past trends in disaster losses. Accordingly, EPA did not rely on a linkage between 

climate change and the economic magnitude of disaster losses to support the Endangerment 

Finding, and petitioners’ arguments do not undermine the reasoning supporting EPA’s 

Endangerment Finding. 

Our response to a petitioner’s specific claims regarding the Muir-Wood study is provided in 

Response 2-5, below. 

Comment (2-5): 

Southeastern Legal Foundation writes: 

The IPCC reported that global warming was causing an increase in losses from weather 

disasters of 2% per year, even after controlling for economic growth, citing a non-peer 

reviewed study by Robert Muir-Wood. Yet the IPCC mischaracterized the study, which 

actually found no trend and expressly eschewed the proposition for which it was cited. 

14 
Muir-Wood et al. expressly caveated that the exceptionally strong hurricane seasons in 

2004 and 2005 accounted for almost all of the 2% increase from 1970-2005. 

Response (2-5): 

First, while the version of the Muir-Wood et al. (2006) paper cited in the IPCC was not yet peerreviewed, a subsequent version of this work was peer-reviewed and accepted for publication just 

weeks after the cutoff for inclusion in the IPCC, according to a statement by Risk Management 

Solutions (RMS), where Robert Muir-Wood is employed as a chief research officer. In a 

frequently asked questions document posted on its website (RMS, 2010), RMS states: 

The research was conducted during the first half of 2006 and the full paper summarizing 

the results was peer reviewed and accepted for publication in November 2006. This was 

a few weeks outside of the cut-off date for the IPCC 4th Assessment Report in October, 

which is why an earlier summary version of the paper—written for a scientific workshop 

held in May 2006 and published in the conference proceedings in October 2006—was 

referenced (the IPCC can only cite published material). Despite not being able to 

reference it, the IPCC was aware of the full report and that it had been accepted for 

publication before the 4th Assessment Report was finalized. 

While the paper was completed and accepted for publication in November 2006, delays 

in publication meant that it did not officially appear as a book chapter until 2008. 

Second, the same frequently asked questions document (RMS, 2010) indicates that the IPCC did 

not mischaracterize the results of the paper: 

RMS believes the IPCC fairly referenced its paper, with suitable caveats around the 

results, highlighting the factors influencing the relationship that had been discovered 

between time and increased catastrophe costs. We believe it was appropriate to include 

the RMS paper in the report because, at that time, it was the only paper addressing global 

multi-peril catastrophe losses over time that had been normalized for changes in the 

values and exposure at risk. 

Thus, we find the study to be valid. As discussed in Response 1-15 of the RTC document, the 

use of non-peer-reviewed literature is allowed under IPCC procedures. In this case, the paper 

was clearly a reasonable reference and was ultimately peer-reviewed. We further find the 

petitioner’s discussion of the caveats in the Muir-Wood paper to be potentially misleading. The 

petitioner claims that “the IPCC mischaracterized the study” and states in the next sentence that 

“Muir-Wood et al. expressly caveated that the exceptionally strong hurricane seasons in 2004 

and 2005 accounted for almost all of the 2% increase from 1970-2005.” This could give the 

impression that the IPCC does not provide such caveats. An examination of the discussion in 

Working Group II’s contribution to the IPCC AR4, however, reveals that it also caveats the 2% 

increase, stating (Rosenzweig et al., 2007): “The significance of the upward trend is influenced 

by the losses in the USA and the Caribbean in 2004 and 2005 and is arguably biased by the 

relative wealth of the USA, particularly relative to India.” 

15 
Comment (2-6): 

Background: Southeastern Legal Foundation cites the following IPCC expert reviewer comment 

(IPCC, 2006c), which was submitted while the Working Group II report was in preparation and 

pertains to the IPCC’s characterization of climate change and disaster losses and the Muir-Wood 

et al. (2006) study: 

I think this is inappropriate. It leads the reader into interpreting recent events in a 

particular way without providing supporting information. This suggestion, that the losses 

in 2004 and 2005 draw Pielke’s results into question, needs to be supported with a 

reference or a solid in-chapter assessment. What does Pielke think about this? (Francis 

Zwiers, Canadian Centre for Climate Modelling and Analysis) 

According to Roger Pielke Jr. (Pielke, 2010a), a professor of environmental studies at the 

University of Colorado, the expert reviewer, Zwiers, is referring to this passage in the AR4 

(Rosenzweig et al., 2007): 

 

A previous normalisation of losses, undertaken for U.S. hurricanes by Pielke and Landsea 

(1998) and U.S. floods (Pielke et al., 2002) included normalising the economic losses for 

changes in wealth and population so as to express losses in constant dollars. These 

previous national U.S. assessments, as well as those for normalised Cuban hurricane 

losses (Pielke et al., 2003), did not show any significant upward trend in losses over time, 

but this was before the remarkable hurricane losses of 2004 and 2005. 

The IPCC writing team responded to the Zwiers comment with the following: “I believe Pielke 

agrees that adding 2004 and 2005 has the potential to change his earlier conclusions – at least 

about the absence of a trend in US Cat losses” (IPCC, 2006c). 

Comment: The Southeastern Legal Foundation claims that “The IPCC knew from the comments 

of reviewers that their use of the [Muir-Wood] study was wrong before the report was 

published.” Citing a blog post from Roger Pielke Jr., Southeastern Legal Foundation suggests 

the IPCC fabricated its response to the expert reviewer, Zwiers: 

The IPCC reviewer had asked “What does Pielke think about this?” The answer given 

was a fabrication, according to Pielke, Jr. As he commented on his blog, “[N]ot only did 

the IPCC AR4 WGII egregiously misrepresent the science of disasters and climate change, 

but when questions were raised about that section by at least one expert reviewer, it 

simply made up a misleading and false response about my views.” 

Response (2-6): 

It is unfortunate that Dr. Pielke found that his views were misrepresented by the IPCC. EPA 

cannot speculate how or why this happened. Dr. Pielke had the opportunity to comment on the 

IPCC’s draft treatment of these issues as a reviewer, but did not. (He is officially listed as an 

IPCC Working Group II expert reviewer for the United States in Appendix III of the IPCC AR4 

Working Group II report (IPCC, 2007f). 

16 
The representative for the IPCC’s author team wrote “I believe Pielke agrees,” which suggests a 

possible honest misunderstanding of Dr. Pielke’s views. This incident certainly does not support 

the petitioner’s contention that the IPCC “knew” that its use of the Muir-Wood study was wrong. 

In fact, as discussed in the previous response (2-5), it is not at all clear that the study was wrong 

or was used inappropriately by the IPCC in any way. 

At the time the Muir-Wood et al. study was completed in 2006, it was the only global analysis 

we are aware of that included 2004 and 2005 data. While it is true that Pielke Jr.’s remarks from 

the Seventh Annual Roger Revelle Commemorative Lecture contained an analysis of normalized 

Atlantic hurricane damages through 2005 and were published in Oceanography (Pielke, 2006), 

those remarks were not assessed by the IPCC, likely because they were presented as a lecture 

rather than a scientific study. Much of the scientific content of Dr. Pielke’s talk was 

subsequently peer-reviewed and published in 2008 (Pielke et al., 2008), but this was well after 

the IPCC deadline for inclusion in the AR4. Furthermore, whereas Dr. Pielke’s 2006 analysis in 

Oceanography limited its focus to Atlantic hurricanes, the Muir-Wood analysis was multi-hazard 

and global. 

Thus, while the IPCC may have made mistaken assumptions about Dr. Pielke’s views, its 

reliance on the Muir-Wood et al. (2006) study was reasonable, as that study contained the latest 

and most relevant published global analysis. 

Comment (2-7): 

The Southeastern Legal Foundation states that EPA’s Response 1-15 (in Volume 1 of the RTC 

document, concerning the use of non-peer-reviewed literature) did not respond to the substance 

of the comment concerning the IPCC’s and Climate Change Science Program’s (CCSP’s) 

misrepresentation of the literature and the central underlying point that there was no legitimate 

evidence that manmade climate change was causing an increase in weather disasters. 

The Southeastern Legal Foundation notes: “This comment showed that both the IPCC and 

especially the CCSP had fraudulently asserted that AGW was causing increased frequency and 

severity of extreme weather events.” It provides the following excerpt from the comment 

(3303): 

In 2007 the IPCC released its Fourth Assessment Report and it relied on the single nonpeer reviewed Muir-Wood (2006) [9] study cherrypicked from the Hohenkammer 

workshop as the single study to highlight in its review of this topic. [12] The same 

critique of the Stern report’s reliance on this Muir-Wood study above applies to the 

IPCC’s reliance on it as well. Further, the IPCC included a graph [13] attempting to 

show how closely temperature anomalies match up with disaster losses, using a scaling of 

the axes to suggest a relationship where none has been shown in the peer-reviewed 

literature. Again it relies on Muir-Wood (2005). Coincidentally, Robert Muir-Wood, of 

Risk Management Solutions, Inc., was an author of the chapter of the IPCC report that 

selectively highlighted his own non-peer reviewed work. 

The US Climate Change Science Program systematically and repeatedly misrepresented 

the science of disasters and climate change. First, the CCSP US extremes report [14] 

miscited several of Roger Peilke’s papers in support of claims that they did not make and 

17 
relied on Mills 2005 as the definitive source on this topic. [16] The disasters and climate 

change section of this CCSP report is also a fact checker’s nightmare. Second the CCSP 

draft Synthesis report and final Synthesis report [15] relied on non-peer reviewed work 

by Evan Mills and ignored relevant peer reviewed research showing different results (in 

fact all peer reviewed research points in the same direction on this subject). 

Coincidentally, Evan Mills was an author of the CCSP Synthesis Report that highlights 

his own non-peer reviewed work. Mills also apparently consults for companies with an 

interest in climate policies, and yet this was not disclosed by the CCSP. 

It then cites EPA’s response (RTC 1-15): 

The commenter describes two pieces of literature that were referenced by IPCC but not 

published in peer reviewed journals: 1) a natural catastrophes report by Munich Re 

(2000) that was cited in IPCC Third Assessment Report (IPCC, 2001), and 2) a paper on 

trends in weather-related catastrophes by Muir-Wood et al. (2006). The identification of 

only two examples out of the thousands of references cited in the IPCC (2000) and 

(2007) reports provides more support for the rigor of the IPCC process. Further, these 

specific studies were neither the central nor sole evidence used in forming the broader 

conclusions of the IPCC; such broader conclusions are based on multiple lines of 

evidence and peer-reviewed literature. 

On the basis of EPA’s response, the Southeastern Legal Foundation concludes: 

It is a very peculiar logic that treats proof of what appears to be scientific fraud as 

demonstrating “the rigor of the IPCC’s process.” No response whatsoever is made to the 

substance of the comment concerning the CCSP’s misrepresentation of the literature and 

the central underlying point that there was no legitimate evidence that manmade climate 

change was causing an increase in weather disasters. The question naturally arises as to 

why the EPA avoided these points. One of the lead authors of the CCSP report so 

vigorously attacked in Comment 3303 is Thomas Wilbanks, of the DOE Oak Ridge 

National Laboratory. The same Thomas Wilbanks was a Federal expert reviewer for the 

TSD. TSD p. 2. Thus, the EPA ignored and avoided the substance of a comment that 

pointed out that a report of which one of its expert reviewers was a lead author had 

“systematically and repeatedly misrepresented the science of disasters and climate 

change.” 

Response (2-7): 

First, EPA’s RTC document, Volume 1, covers EPA’s “General Approach to the Science and 

Other Technical Issues,” not the substantive issues pertaining to climate change and disaster 

losses. Those issues are discussed in RTC Volume 7, “Water Resources, Coastal Areas, and 

Ecosystems and Wildlife.” Specifically, RTC 7-38 address substantive issues pertaining to 

climate change and disaster losses raised by commenters (as does RTC 7-5) as discussed in 

Response 2-4 above. Accordingly, EPA’s commentary on the Muir-Wood literature in Volume 

1 focuses on process issues, and the scientific issues are addressed in Volume 7. 

18 
Furthermore, as we indicate in Response 2-5 above, a subsequent version of Muir-Wood et al. 

(2006) was, in fact, peer-reviewed and accepted for publication just weeks after the IPCC cutoff 

according to RMS. Irrespective of the peer review issue, we reiterate our conclusion from RTC 

1-15: “...these specific studies were neither the central nor sole evidence used in forming the 

broader conclusions of the IPCC; such broader conclusions are based on multiple lines of 

evidence and peer-reviewed literature.” The magnitude of observed disaster losses from extreme 

events in general, and the Muir-Wood study in particular, were not central to EPA’s 

Endangerment Finding. 

We discuss allegations that the IPCC misrepresented the literature on observed climate change 

and disaster losses in Response 2-5. With respect to the “graph [13, IPCC Supplementary 

Material Figure SM1.1, Working Group II AR4, 2007] attempting to show how closely 

temperature anomalies match up with disaster losses” referred to in the cited comment (3303) 

above, we note that said graph was not cited or relied upon in the Endangerment Finding and, 

furthermore, that it did not appear in the main IPCC Working Group II report but in 

supplementary material. We acknowledge this graph is controversial. RMS, for example, stated 

the following in its frequently asked questions document pertaining to climate change and 

disaster losses (RMS, 2010): 

A graph showing averaged global temperature and averaged catastrophe loss since 1970 

was included in supplementary material rather than the IPCC report itself and was not 

itself published. RMS believes that the graph could be misinterpreted and should not 

have been included in these materials. 

Despite this statement, the inclusion of one controversial graph in supplementary material does 

not compromise the IPCC’s credibility or legitimacy. 

The charges that CCSP (and hence USGCRP) miscited and misrepresented Roger Pielke Jr.’s 

work, over-relied on the work of Evan Mills, and ignored some other studies on the issue of 

climate change and disaster loss are difficult to assess as they were made in blog posts (of Roger 

Pielke Jr. (Pielke, 2010b)), represent the perspective of one individual (Roger Pielke Jr.), and 

have not been published in any official capacity (e.g., in the peer-reviewed literature). However, 

they do not materially affect the basis for EPA’s Endangerment Finding. Dr. Pielke himself 

stated: “...I am of the view that the Obama Administration is perfectly justified in advancing the 

[Endangerment] finding” (Pielke, 2010b). As we state in Response 2-4, EPA did not focus on 

historical trends in the magnitude of economic disaster losses to evaluate the likelihood that 

climate change would lead to an increase in the number or frequency of extreme weather events. 

Furthermore, in RTC 7-5 we cite the CCSP (2008) statement acknowledging that the relative 

contribution of climate change and socioeconomic vulnerability (to weather and climate 

extremes) to observed increases in disaster costs are “subject to debate.” 

Finally, the fact that Robert Muir-Wood and Evan Mills were selected as authors for chapters in 

the IPCC and CCSP, respectively, and may have cited their own work does not delegitimize 

these assessments or their findings. Rather, it is only appropriate that leading experts on these 

topics—familiar with the range of literature—would be asked to assist in these assessments. 

Petitioners provide no evidence to support the allegation that Evan Mills’ work was 

19 
compromised or biased; speculating that he “apparently” does consulting for companies “with an 

interest in climate policies” is innuendo, not proof. 

Lastly, the fact that Thomas Wilbanks was an expert reviewer for EPA’s TSD (U.S. EPA, 2009) 

and was lead author of a report that the petitioner alleges “systematically and repeatedly 

misrepresented the science of disasters and climate change” is irrelevant. As we state in 

Response 2-4, EPA did not discuss observed climate change and disaster losses in the TSD. 

Thus, though we discuss some of CCSP’s conclusions in RTC 7-5 and 7-38 that focus on the 

challenges in linking observed climate change and disaster losses, CCSP’s treatment of this issue 

was not and is not materially relevant to the Endangerment Finding. Furthermore, the petitioner 

does not present evidence Wilbanks played any role in the presentation of material on this issue. 

Thus, the charge that EPA “ignored and avoided” the substance of the comment on disasters and 

climate change because of Wilbanks is unsupported and false. EPA relied on a team of federal 

experts to ensure that EPA was correctly synthesizing the existing assessment literature in the 

TSD. As RTC 1-10 states: 

....the purpose of the federal expert review was to ensure that the TSD accurately 

summarized the conclusions and associated uncertainties from the assessment reports. 

The federal experts were ideal candidates because they have contributed significantly to 

the body of climate change literature and played active roles in IPCC and CCSP—

therefore making them experts on various aspects of climate science and very familiar 

with the underlying literature and state of the science. Furthermore, the federal climate 

change experts represent a range of technical specialties that span the range of topics 

covered in the TSD and covered by the range of topics that the Administrator needed to 

consider. In addition, the federal experts were not involved with developing the TSD or 

Findings in any way other than their review roles. 

 

Petitioners are making a very serious accusation—that “what appears to be scientific fraud” 

occurred—without providing supporting scientific evidence. Instead, they mischaracterize 

EPA’s actions in claiming that disaster losses are central to the Endangerment Finding when they 

clearly are not. They mischaracterize EPA’s treatment of comments on the proposed 

Endangerment Finding by implying that we did not address the issues surrounding disaster 

losses, when the issue is clearly addressed in the appropriate volume of the RTC. And they 

impugn the integrity of several scientists, on the basis of speculation not evidence, seemingly for 

no other reason than that they disagree with the conclusions of the assessment literature. 

2.1.5 Validity of Alps, Andes, and African Mountain Snow Impacts 

Comment (2-8): 

Several petitioners (the Competitive Enterprise Institute, the Ohio Coal Association, Peabody 

Energy, the State of Texas, and the Southeastern Legal Foundation) argue that claims of glacier 

melt in the Andes, the Alps, and parts of Africa arise from anecdotal comments in a magazine 

article and a master thesis. They challenge the IPCC’s use of this non-peer-reviewed literature, 

suggesting the findings may be suspect. The Southeastern Legal Foundation states: “The EPA 

should reconsider its reliance on the IPCC’s reporting now that the IPCC’s conclusion has been 

shown to be so poorly supported.” 

20 
Response (2-8): 

The citations referred to by petitioners regarding the reduction of mountain ice in the Andes, 

Alps, and Africa are actually references to “loss of ice climbs,” not assessments of mountain 

glacier retreat. Loss of ice climbs is an example of the observed effects of warming on the icecovered areas of the Earth. In this context, these citations are appropriate and within the IPCC’s 

guidelines on the use of so-called gray literature. They provide additional evidence consistent 

with the well-supported peer-review conclusions that snowpack is declining in many places and 

that glaciers are melting worldwide. Note that we respond to petitioners’ broader claims 

regarding the IPCC’s use of gray literature in Subsection 2.2.4.4. 

Furthermore, as the finding in question pertains to indicators outside the United States, the 

petitioners’ claims are not relevant to the Endangerment Finding. As noted in Subsection 2.1.1, 

the Endangerment Finding states (Section III.D): “The Administrator looked first at impacts in 

the United States itself, and determined that these impacts are reasonably anticipated to endanger 

the public health and the welfare of the U.S. population. That remains the Administrator’s 

position, and by itself supports her determination of endangerment.” 

EPA did not rely on these specific references or refer to “loss of ice climbs” as an indicator of 

climate change. Our primary focus was on the implications of climate change for the United 

States, and we relied on peer-reviewed literature to assess these impacts. We did not refer to this 

specific issue in either the TSD or the Endangerment Finding, and we did not include any 

discussion on “loss of ice climbs.” The TSD does include discussion of mountain glacier retreat, 

based on peer-reviewed literature, which the petitioners do not critique. 

2.1.6 Validity of Amazon Rainforest Dieback Projection 

Comment (2-9): 

Several petitioners (the Competitive Enterprise Institute, the Ohio Coal Association, Peabody 

Energy, the State of Texas, the Southeastern Legal Foundation) challenge the IPCC’s statement 

that “[U]p to 40% of the Amazonian forests could react drastically to even a slight reduction in 

precipitation,” alleging that it arises from gray literature and cannot be substantiated. The 

Southeastern Legal Foundation states that the source for the IPCC’s statement, Nepstad et al. 

(1999) from the journal Nature, “does not support the IPCC’s assertion”. Peabody states that 

“the Nature article does not contain the 40% figure” and “the provenance of the IPCC’s striking 

‘40%’ figure is uncertain.” The Competitive Enterprise Institute finds that “the IPCC claim that 

the findings in AR4 are based on peer reviewed science is false.” 

Response (2-9): 

First, we note that this issue is not discussed anywhere in the TSD or Endangerment Finding, and 

is thus of little relevance to the Finding. Second, while we agree that the IPCC cited gray 

literature in this case—i.e., Rowell and Moore (2000), a report of the World Wildlife 

Federation—we note that the underlying studies supporting the Rowell and Moore report are, in 

fact, peer-reviewed. 

21 
In response to the publicity surrounding this purportedly unsubstantiated finding in the IPCC 

AR4, Daniel Nepstad—a senior scientist at Woods Hole Research Center and author of the study 

(Nepstad et al., 1999) that contained the finding referred to by Rowell and Moore—issued a 

statement on this matter. In the statement, he noted that the citations listed in the Rowell and 

Moore report were incomplete but that the AR4’s statement on Amazon forest susceptibility to 

rainfall reduction was correct. Here is the relevant excerpt from his statement (Nepstad, 2010): 

The IPCC statement on the Amazon is correct, but the citations listed in the Rowell and 

Moore report were incomplete. (The authors of this report interviewed several 

researchers, including the author of this note, and had originally cited the IPAM website 

where the statement was made that 30 to 40% of the forests of the Amazon were 

susceptible to small changes in rainfall). Our 1999 article (Nepstad et al. 1999) estimated 

that 630,000 km2 of forests were severely drought stressed in 1998, as Rowell and Moore 

correctly state, but this forest area is only 15% of the total area of forest in the Brazilian 

Amazon. In another article published in Nature, in 1994, we used less conservative 

assumptions to estimate that approximately half of the forests of the Amazon depleted 

large portions of their available soil moisture during seasonal or episodic drought 

(Nepstad et al. 1994). After the Rowell and Moore report was released in 2000, and prior 

to the publication of the IPCC AR4, new evidence of the full extent of severe drought in 

the Amazon was available. In 2004, we estimated that half of the forest area of the 

Amazon Basin had either fallen below, or was very close to, the critical level of soil 

moisture below which trees begin to die in 1998. This estimate incorporated new rainfall 

data and results from an experimental reduction of rainfall in an Amazon forest that we 

had conducted with funding from the US National Science Foundation (Nepstad et al. 

2004). Field evidence of the soil moisture critical threshold is presented in Nepstad et al. 

2007. 

Specifically, we note that the Nepstad et al. (2004) study states: “Increases in ET [evapotranspiration] of only 15% or similar reductions in rainfall can lead to severe soil moisture 

deficits over roughly half of the Amazon.” This statement certainly is consistent with the 

statement “Up to 40% of the Amazonian forests could react drastically to even a slight reduction 

in precipitation” in the IPCC AR4. 

Nepstad’s 2010 statement in response to this controversy reached the following conclusion 

(Nepstad, 2010): 

In sum, the IPCC statement on the Amazon was correct. The report that is cited in 

support of the IPCC statement (Rowell and Moore 2000) omitted some citations in 

support of the 40% value statement. 

Similarly, in its report Assessing an IPCC Assessment, PBL (2010a) identified a problem with 

the IPCC’s referencing of this finding, but not the finding itself. It states: 

More adequate peer-reviewed, scientific journal literature would have been available to 

support this statement, such as Cox et al. (2000; 2004) (C6). This minor comment has no 

consequences for the IPCC conclusions in the various Summaries for Policymakers. 

22 
Finally, the United Kingdom’s Sunday Times newspaper, which reported the alleged problem 

with the IPCC’s representation of this issue on January 31, 2010 (Sunday Times, 2010), has 

subsequently reversed itself, arriving at the same conclusion as Nepstad. Consequently, it 

removed the article from its website and printed a correction on June 20, 2010 (Sunday Times, 

2010), which stated in part: 

The article “UN climate panel shamed by bogus rainforest claim” (News, Jan 31) stated 

that the 2007 Intergovernmental Panel on Climate Change (IPCC) report had included an 

“unsubstantiated claim” that up to 40% of the Amazon rainforest could be sensitive to 

future changes in rainfall. The IPCC had referenced the claim to a report prepared for the 

World Wildlife Fund (WWF) by Andrew Rowell and Peter Moore, whom the article 

described as “green campaigners” with “little scientific expertise.” The article also stated 

that the authors’ research had been based on a scientific paper that dealt with the impact 

of human activity rather than climate change. 

In fact, the IPCC’s Amazon statement is supported by peer-reviewed scientific evidence. 

In the case of the WWF report, the figure had, in error, not been referenced, but was 

based on research by the respected Amazon Environmental Research Institute (IPAM) 

which did relate to the impact of climate change. We also understand and accept that Mr 

Rowell is an experienced environmental journalist and that Dr Moore is an expert in 

forest management, and apologise for any suggestion to the contrary. 

To summarize, contrary to the assertions of the petitioners, though the IPCC may have not 

adequately referenced the Amazon finding, the basis for its statement originated from and is 

supported by peer-reviewed literature. Furthermore, as this finding is specific to the Amazon 

region, petitioners’ claims are not relevant to the Endangerment Finding. As noted in Subsection 

2.1.1, the Endangerment Finding states (Section III.D): “The Administrator looked first at 

impacts in the United States itself, and determined that these impacts are reasonably anticipated 

to endanger the public health and the welfare of the U.S. population. That remains the 

Administrator’s position, and by itself supports her determination of endangerment.” 

For further discussion on petitioners’ broader claims regarding the IPCC’s use of gray literature, 

please refer to Subsection 2.2.4.4. 

2.1.7 Validity of African Rain-Fed Agriculture Projection 

The comments and responses in this section refer to the following statement pertaining to crop 

yields in Africa from Chapter 9 of Working Group II’s contribution to the IPCC AR4 (Boko et 

al., 2007): 

In other countries [of Africa] additional risks that could be exacerbated by climate change 

include greater erosion, deficiencies in yields from rain-fed agriculture of up to 50% 

during the 2000-2020 period, and reductions in the crop growth period (Agoumi, 2003). 

A version of this statement appeared in the IPCC’s AR4 Synthesis Report (IPCC, 2007b): 

23 
By 2020, in some countries, yields from rain-fed agriculture could be reduced by up to 

50%. Agricultural production, including access to food, in many African countries is 

projected to be severely compromised. This would further adversely affect food security 

and exacerbate malnutrition. 

A similar statement also appeared in the IPCC’s AR4 Working Group II Summary for 

Policymakers (IPCC, 2007c): 

Agricultural production, including access to food, in many African countries and regions 

is projected to be severely compromised by climate variability and change. The area 

suitable for agriculture, the length of growing seasons and yield potential, particularly 

along the margins of semi-arid and arid areas, are expected to decrease. This would 

further adversely affect food security and exacerbate malnutrition in the continent. In 

some countries, yields from rain-fed agriculture could be reduced by up to 50% by 2020. 

The same statement (from IPCC, 2007c) was incorporated into EPA’s TSD (U.S. EPA, 2009) 

within Table 16.1: “Examples of Key Regional Impacts as Identified by IPCC.” 

Comment (2-10): 

The Competitive Enterprise Institute, the Ohio Coal Association, Peabody Energy, and the 

Southeastern Legal Foundation take issue with a statement in Section 16(b) of the TSD that: “In 

some countries, yields from rain-fed agriculture could be reduced by up to 50% by 2020.” They 

claim the statement originated from gray literature in the IPCC AR4 and is therefore illegitimate. 

Southeastern Legal Foundation concludes: “The African Crop Yields claim stands as another 

example of the IPCC making a claim of imminent disaster that inappropriately relied on nonpeer-reviewed literature...” 

Response (2-10): 

The IPCC statement cites a report by Dr. Ali Agoumi, a climate expert from Morocco (Agoumi, 

2003) that was published by the International Institute for Sustainable Development (IISD) and 

funded by the government of Canada, the U.S. Agency for International Development, and other 

public and private institutions. Based on EPA’s review of the report, it appears that the 50% 

number was not obtained from the peer-reviewed literature but rather from “vulnerability studies 

on three North African countries (Algeria, Morocco and Tunisia) with respect to climatic 

changes.” These vulnerability studies were prepared under the U.N. Environment Programme 

Global Environment Fund and included in the National Communications of these three countries 

to the U.N. Framework Convention on Climate Change (Ministry of Territory Development and 

Environment, 2001, Kingdom of Morocco, 2001 and Republic of Tunisia, 2001). 

In response to publicity regarding this purportedly unsubstantiated statement in the IPCC report, 

Dr. Coleen Vogel, a contributing lead author of the IPCC chapter on Africa impacts, described 

the context in which Dr. Agoumi’s research was used. She explained that Agoumi’s report 

received rigorous scrutiny by her fellow authors and was thoroughly discussed during 

development of the chapter (Kretzmann, 2010). She explained that the decision to include this 

(gray literature) study was based on the paucity of peer-reviewed material relating to some parts 

24 
of the world, particularly Africa, and the desire of the authors of the report to provide balanced 

information. The process described by Dr. Vogel is consistent with the IPCC’s guidance on the 

use of gray literature, as previously described in Volume 1 of the RTC document and further 

discussed in Subsection 2.2.4.4 of this Response to Petitions (RTP) document. 

Finally, we note that this statement relates to impacts outside the United States, and it did not 

materially impact the determination of endangerment of public health and welfare in the United 

States. As noted in Subsection 2.1.1, the Endangerment Finding states (Section III.D): “The 

Administrator looked first at impacts in the United States itself, and determined that these 

impacts are reasonably anticipated to endanger the public health and the welfare of the U.S. 

population. That remains the Administrator’s position, and by itself supports her determination 

of endangerment.” 

Comment (2-11): 

Referring to an analysis published by Ben Pile, co-editor of the blog climateresistance.org (on 

the blog of Roger Pielke, Jr.) (Pile, 2010), the Southeastern Legal Foundation states that the 

primary reference supporting the IPCC’s statement on African crop yields “Vulnerability of 

North African Countries to Climatic Changes” (Agoumi, 2003) was from IISD, an advocacy 

group. 

Regarding the IISD reference, Peabody Energy states: 

Thus, the EPA based its findings on the IPCC WGII report, which based its findings on a 

report [the IISD report] published by an organization with a declared political interest in 

climate change that based its findings from an assessment of other non-peer reviewed 

national studies. This is not the way EPA science should be carried out. 

Response (2-11): 

The implication that the credibility of IPCC’s statement on African crop yields is diminished 

because the IPCC’s source (Agoumi, 2003) for the statement was published by an advocacy 

organization or an organization with a “declared political interest in climate change” is 

unsupported. The organization in question is IISD, which describes itself as follows: 

The International Institute for Sustainable Development contributes to sustainable 

development by advancing policy recommendations on international trade and 

investment, economic policy, climate change, measurement and indicators, and natural 

resource management. By using Internet communications, we report on international 

negotiations and broker knowledge gained through collaborative projects with global 

partners, resulting in more rigorous research, capacity building in developing countries 

and better dialogue between North and South. 

IISD’s vision is better living for all—sustainably; its mission is to champion innovation, 

enabling societies to live sustainably. IISD receives operating grant support from the 

Government of Canada, provided through the Canadian International Development 

Agency (CIDA) and Environment Canada, and from the Province of Manitoba. The 

institute receives project funding from the Government of Canada, the Province of 

25 
Manitoba, other national governments, United Nations agencies, foundations and the 

private sector. IISD is registered as a charitable organization in Canada and has 

501(c)(3) status in the United States. 

We find no reason to question the credibility and legitimacy of information produced by this 

organization on the basis of either its mission or funding sources. Moreover, neither the 

Southeastern Legal Foundation nor Peabody Energy provide any support for the implication that 

work by an organization such as IISD is automatically suspect or flawed. 

Finally, Peabody Energy’s statement that EPA’s findings are based on this material is incorrect. 

As noted in Subsection 2.1.1, the Endangerment Finding states (Section III.D): “The 

Administrator looked first at impacts in the United States itself, and determined that these 

impacts are reasonably anticipated to endanger the public health and the welfare of the U.S. 

population. That remains the Administrator’s position, and by itself supports her determination 

of endangerment.” 

We discuss the legitimacy of the science and underlying references for the African crop yields 

statement in Response 2-12. 

Comment (2-12): 

The Southeastern Legal Foundation alleges that EPA uncritically adopted the IPCC’s “faulty 

conclusion” with respect to crop yields. It refers to a blog by writer/commentator Richard North 

(North, 2010) to conclude the Agoumi (2003) reference cited by the IPCC on the issue of rainfed agricultural yields in Africa relies on studies that “do not support the proposition for which 

they are cited.” 

Relying on Richard North’s blog, the Southeastern Legal Foundation summarizes the 

vulnerability studies cited by Agoumi (2003) from the National Communications of Morocco, 

Tunisia, and Algeria. The Southeastern Legal Foundation notes that the Morocco National 

Communication “lends some support [to the Agoumi reference], saying that by 2020 during 

drought conditions cereal yields would decline up to 50%” but that “the data apply to cereal 

yields only, not crops in general as is implied by the IPCC.” The Southeastern Legal Foundation 

further states that “Algeria’s report said their yields would double, and be trimmed only slightly 

by ‘climate change’” and “Tunisia’s submission concluded the picture was mixed, but they could 

have an increase in rain and agricultural production.” 

Response (2-12): 

The IPCC’s statement on rain-fed agriculture in Northern Africa is not “faulty” and the 

Southeastern Legal Foundation presents no evidence that it was included uncritically in EPA’s 

TSD. Furthermore, the Southeastern Legal Foundation’s portrayal of findings on climate and 

crop yields from the National Communications of Morocco, Tunisia, and Algeria derived from 

Richard North’s blog is not complete. When all of the information in these National 

Communications is considered, we find there is broad support for Agoumi’s (2003) statements 

on North African rain-fed agriculture, which are: 

26 
 “Some of the key statistics regarding water, soil, urban areas and coastal zones are 

outlined below. . . . Decreasing rain-based agricultural yields with grain yields reduced 

by up to 50 percent in periods of drought.” 

 “Studies on the future of vital agriculture in the region have shown the following risks, 

which are linked to climate change: . . . deficient yields from rain-based agriculture of up 

to 50 percent during the 2000–2020 period.” 

PBL, in its report Assessing an IPCC Assessment (PBL, 2010a), makes the following important 

point with respect to IPCC’s statement on rain-fed agriculture in Africa: 

This statement is not directly a statement on climate change, but on climate variability: in 

individual years, droughts can cause up to 50% in yield reductions. The implicit message 

here is that when droughts would become more frequent due to climate change, more 

years with up to 50% in yield reductions would occur. The statement could easily 

mislead readers into thinking that average annual yields could be reduced by up to 50% 

due to climate change. In the Summary for Policymakers of the Working Group II 

Report, the paragraph that contains this statement starts with a sentence introducing the 

notion of climate variability, which puts the statement more into context. 

It is possible that petitioners misinterpreted the IPCC’s statement as suggesting that the IPCC’s 

projection was on the basis of climate change alone, given the Southeastern Legal Foundation’s 

assertion, for example, that IPCC was projecting “imminent disaster.” While we agree with PBL 

that the IPCC’s statement could easily mislead readers without the proper context, we note that, 

before quoting the IPCC’s projection on rain-fed agriculture, EPA’s TSD includes the statement 

“Agricultural production, including access to food, in many African countries and regions is 

projected to be severely compromised by climate variability [emphasis added] and change.” 

Therefore, EPA provided the proper context for the IPCC’s conclusion. 

With respect to the basis for the conclusion itself, the following excerpts from the three 

countries’ National Communication reports on the issues of climate variability and change, 

precipitation, and crop yields provide broad support for the Agoumi (2003) statements along 

with accompanying discussion: 

 The National Communication of Morocco states (Kingdom of Morocco, 2001): 

The development of climate scenarios for Morocco according to IPCC 

methodology reveals the following results: . . . 

 A trend towards a decrease in average annual rainfall volume by about 4% 

in 2020 compared to 2000 levels. . . . 

 An increase in the frequency and intensity of droughts in the south and the 

east of the country. 

27 
The first quantitative estimate of possible CC [climate change] impacts on water 

resources in 2020 points to the fact that there would be an average and general 

decrease in water resources (in the order of 10 to 15 %...). 

The study of CC [climate change] impacts on agriculture (dominated by cereal 

cultivation) in 2020 unfolds the following results: A decrease in cereal yields by 

50% in dry years and 10% in normal years. 

As the Southeastern Legal Foundation admits, the numbers from Morocco’s National 

Communication lend support to the statement in Agoumi (2003) that “studies on the 

future of vital agriculture in the region have shown the following risks, which are linked 

to climate change: . . . deficient yields from rain-based agriculture of up to 50 per cent 

during the 2000–2020 period.” 

Richard North’s contention (North, 2010, as referred to by the Southeastern Legal 

Foundation) that “the data apply to cereal yields only, not crops in general as is implied 

by the IPCC” is arguable considering that Morocco’s National Communication 

indicates that agriculture is “dominated by cereal cultivation.” Thus, it is not 

unreasonable to use cereal cultivation as a proxy for all of agriculture in this cerealcrop-dominated region. 

 The National Communication of Algeria (Ministry of Territory Development and 

Environment, 2001) states:1

Because of global warming, we must brace ourselves for chronic climate 

instability and greater frequency of droughts and floods. Droughts damage soils 

and floods destroy ground cover and contribute to the erosion of soils. With 

longer spans of time between dry and wet spells comes an even greater impact 

due to erosion. The southern regions of the country will be most directly 

impacted by increased temperatures and will be subject to the numerous 

consequences of accelerated desertification. The increased risk of drought 

presents the greatest challenge as a result of climate change. The 

Intergovernmental Panel on Climate Change (IPCC) expect that the desert regions 

will extend northward in the Maghreb. 

The above text provides a clear qualitative description of the risks climate change pose to 

agriculture in Algeria. In addition, this information from the National Communication of 

Algeria provides quantitative output from a model known as CROPWAT, which 

estimates changes in crop yields using climate change projections obtained from two 

general circulation models. The National Communication of Algeria reports: 

... one can consider an average reduction in the output cereal of about 5.5 to 

6.8%, corresponding mainly to instances of climate change [in 2020]( Ministry of 

Territory Development and Environment, 2001) 

 

1

 The excerpt that follows was professionally translated from French. 

28 
When considering these quantitative cereal yield changes, it is very important to note that 

these percentages refer to changes in cereal yields resulting primarily from climate 

change alone and not climate variability and change combined. The climate and hence 

precipitation variability in northern Africa can be quite large. For example, in the report 

Assessing an IPCC Assessment (PBL, 2010a), PBL states “...the [IPCC] authors made 

plausible that, due to current climate variability, the yields in Algeria, Morocco and 

Tunisia have been varying annually, including yield reductions of nearly 70% in 

individual years, in the period between 2000 and 2006.” 

In other words, if these yield reductions resulting from greenhouse gas–induced climate 

change were superimposed on the yield reductions that might occur during a particularly 

dry period arising from the region’s characteristic precipitation variability, they would be 

higher and comparable with the results from the Morocco National Communication. 

Finally, the Southeastern Legal Foundation’s reference to the Algeria National 

Communication’s projections for net increases in cereal projections in 2020 (relative to 

prior decades) is irrelevant and misleading. These increases are related not to climate 

variability and change but to changing agricultural practices and technology. Algeria’s 

National Communication makes clear that the effect of climate change on cereal yields is 

projected to be negative. 

 

 The National Communication of Tunisia states (Republic of Tunisia, 2001): 

...Tunisia is in a hydrous stress situation close to a shortage, sharpened by a high 

anthropic pressure. So minor they be, the Climate Changes can so, result in 

harmful consequences on water resources, on ecosystems depending of water, and 

on the different economic activities that need large quantities of water such as 

agriculture and tourism. 

By modifying the evaporation and precipitation rate, the global warming will 

probably affect the hydrous climate balance and therefore the Tunisian water 

resources. In this way, if the intensification of the evaporation can lead to a 

possible important increase of the rain falls, it might not be sufficient to offset the 

decrease of the sweet water resources. Moreover, due to the global warming, the 

rain situation can be characterized by a bigger frequency of rains resulting from 

torrential storms and downpours, disappearing generally in streaming waters 

rather than be absorbed by the soils. 

This information in the Tunesian National Communication does not provide any 

quantitative estimates of climate variability and/or change on rain-fed agriculture, but the 

clear qualitative implication is that climate changes—both drought and heavy 

precipitation events—will stress agriculture in Tunisia. We, therefore, find that the 

Southeastern Legal Foundation’s statement that “Tunisia’s submission concluded the 

picture was mixed, but they could have an increase in rain and agricultural production” is 

an overly optimistic interpretation of clearly expressed negative impacts. 

29 
Overall, these three National Communications (Morocco, Algeria, and Tunisia) provide 

qualitative support for the fact the climate change will likely stress rain-fed agriculture in 

northern Africa, consistent with the portrayal of Agoumi (2003) and the IPCC. The National 

Communication of Morocco presents quantitative information consistent with what is reported 

by Agoumi (2003) and the IPCC (and hence the TSD), while the National Communication of 

Algeria provides quantitative information that is consistent with these sources when factoring in 

precipitation variability in addition to climate change. The National Communication of Tunisia 

does not provide quantitative information. 

Our view of the literature behind Agoumi (2003) provides considerable evidence that the 

scientific basis for the IPCC’s conclusion is legitimate. The PBL assessment of the IPCC notes 

that “...additional explanations could have provided further foundations for the statement, had 

they been included in [IPCC’s Working Group II] Chapter 9.” We concur, but the Southeastern 

Legal Foundation conclusion that “...there is no support for the IPCC’s dramatic pronouncement 

on African crop yields” is significantly overstated. 

Comment (2-13): 

The Southeastern Legal Foundation provides the following reaction to the African rain-fed 

agriculture projection, which appeared in the Sunday Times (Leake, 2010a) and comes from 

former IPCC chair Robert Watson: “Any such projection [pertaining to African crop yields] should 

be based on peer-reviewed literature from computer modeling of how agricultural yields would 

respond to climate change. I can see no such data supporting the IPCC report.” 

Response (2-13): 

Watson may not have appreciated that peer-reviewed modeling studies of climate change impacts on 

agriculture in parts of Africa are limited. As the IPCC’s AR4 WGI report states (Christensen et al., 

2007): “Several climate change projections based on RCM (regional climate model) simulations are 

available for southern Africa, but are much scarcer for other regions.” Accordingly, as we discuss in 

Subsection 2.2.4.4 of this RTP document, the IPCC references gray literature in these circumstances. 

We also note in Response 2-10 that these studies are not central to the TSD or the Endangerment 

Finding. Finally, though we discuss some additional modeling studies pertinent to Africa in RTP 2-

15, those modeling studies (Parry et al., 2005 and Hulme et al., 2001) were conducted at the global 

and continental scales and contain limited results pertinent to northern Africa specifically. 

Comment (2-14): 

The Southeastern Legal Foundation states that EPA ignored contrary peer-reviewed literature 

and submits literature that the Sahel is greening (from National Geographic and several studies) 

in contrast to “IPCC horror stories” (projecting reductions in rain-fed agriculture). 

Response (2-14): 

EPA is aware of the literature cited by the petitioner that suggests greening in parts of the Sahara 

and Sahel (e.g., Seaquisti, et al., 2009; Anyamba, and Tucker, 2005; Hutchinson et al., 2005; Olsson 

et al., 2005). The issue raised by petitioners is not new and was raised and responded to through 

the public comment process (see Response 2-73 in Volume 2 of the RTC document). Thus, 

these objections do not meet the test in Clean Air Act (CAA) Section 307(d)(7)(B) that it be 

impracticable to raise the objection during the public comment period or the reasons for the 

30 
objection arose between June 24, 2009, and February 16, 2010. Nonetheless, we have reviewed 

these arguments and respond once again. 

The fact that precipitation has increased recently in this region, as we note in our TSD in Section 

4(d), does not mean that a combination of climate variability and change could not substantially 

reduce rain-fed agriculture in the future. The climate in this region is highly variable and while it 

has been relatively wet over the past decade or so, severe drought impacted the region for several 

decades from the 1960s to the 1990s and dry patterns could return to the region. As one of the 

studies (Nicholson, 2005) cited by the petitioner states: “The fluctuations between ‘wet’ and 

‘dry’ in the Sahel/Soudan zones are extreme even on decadal and multi-decadal time scales.” 

Therefore, if the current wet period reverses to a dry period, the impacts of rain-fed agriculture 

on the region could be profound, especially when considering the potential enhancement of the 

drying from human-induced warming (i.e., climate change). 

Finally, we note that the literature presented relates to impacts outside the United States, and it 

did not materially impact the determination of endangerment of public health and welfare in the 

United States. As noted in Subsection 2.1.1, the Endangerment Finding states (Section III.D): 

“The Administrator looked first at impacts in the United States itself, and determined that these 

impacts are reasonably anticipated to endanger the public health and the welfare of the U.S. 

population. That remains the Administrator’s position, and by itself supports her determination 

of endangerment.” 

Comment (2-15): 

The Southeastern Legal Foundation suggests that the IPCC ignored literature that drew different 

conclusions on the issue of rain-fed agriculture projections in Africa, specifically referring to two 

studies: Parry et al., 2005 and Hulme et al., 2001. The Southeastern Legal Foundation states: 

“Both Parry’s own paper and Hulme’s paper were known to and available to Professor Parry [cochair of IPCC Working Group II] in composing the WGII Report and the Synthesis Report. Yet, 

Parry’s WGII report ignored his own paper and that of Hulme, which did not predict disaster, and 

instead relied on one that did, the Agoumi paper, even though it did so incorrectly and 

improperly and was not peer-reviewed.” The Southeastern Legal Foundation further notes that 

Hulme et al. (2001) were careful to note uncertainties in understanding African climate change, 

and implies that the IPCC was not as careful. 

Response (2-15): 

We have reviewed these papers (Parry et al., 2005, and Hulme et al., 2001) and find that, while not 

directly comparable with Agoumi (2003), they do not contradict that source. We also find, 

contrary to the Southeastern Legal Foundation’s assertion, that both of these studies were in fact 

cited by the IPCC, although not always in the same section or context as Agoumi (2003). 

The Parry et al. (2005) study reports the results of a series of research projects that aimed to 

evaluate the implications of climate change for food production and risk of hunger. The analysis 

in this study is performed at global and continental scales rather than the regional scale. This is 

likely why it is not discussed in Chapter 5 of Working Group II’s contribution to the AR4 

(Easterling et al., 2007), where Agoumi (2003) is cited in a section focusing on regional impacts 

in Africa (specifically on Morocco, Algeria, and Tunisia). The Parry et al. (2005) study is cited 

31 
multiple times in Chapter 5 of Working Group II’s contribution (“Food, Fiber, and Forest 

Products,” Easterling et al., 2007), which provides a global perspective. Therefore, Parry did not 

“ignore his own paper” as stated by the Southeastern Legal Foundation. 

One of the primary conclusions of Parry et al. is that “the region of greatest risk [of losses in 

food production, and hunger due to climate change] is Africa.” Parry et al. (2005) provide 

specific cereal yield projections for the 2020s and 2080s resulting from different GHG emission 

scenarios. They state for the globe: “By the 2020s, small changes in cereal yield are evident in 

all scenarios, but these fluctuations are within historical variations.” For the 2080s, Parry et al. 

(2005) provide projections specific to Africa – but not northern Africa specifically, stating that 

climate change could reduce cereal yields by up to 30%. Importantly, the changes in cereal yield 

projected for the 2020s and 2080s are driven by GHG-induced climate change and likely do not 

fully capture interannual precipitation variability which can result in large yield reductions 

during dry periods, as the IPCC (Christensen et al., 2007) states: “...there is less confidence in 

the ability of the AOGCMs (atmosphere-ocean general circulation models) to generate 

interannual variability in the SSTs (sea surface temperatures) of the type known to affect African 

rainfall, as evidenced by the fact that very few AOGCMs produce droughts comparable in 

magnitude to the Sahel droughts of the 1970s and 1980s.” Given the different scopes of the two 

analyses, it is misleading to state that the Parry et al. projections are inconsistent with the 

Agoumi (2003) yield projections. 

The Hulme et al. (2001) study, which reviews observed (1900–2000) and possible future (2000–

2100) continent-wide changes in temperature and rainfall over Africa, is also not ignored by the 

IPCC, contrary to the assertion of the petitioner. In fact, it is cited twice in IPCC’s Working 

Group II Chapter 9 on Africa (Boko et al., 2007): 

 Hulme et al. (2001) is cited in a statement about the complexity of African climatology: 

“Other factors that complicate African climatology include dust aerosol concentrations 

and sea-surface temperature anomalies, which are particularly important in the Sahel 

region (Hulme et al., 2001; Prospero and Lamb, 2003) and southern Africa (Reason, 

2002), deforestation in the equatorial region (Semazzi and Song, 2001; Bounoua et al., 

2002)...” 

 Hulme et al. (2001) is also cited in a statement pertaining to uncertainties in precipitation 

projections in the western Sahel (Boko et al., 2007): “For the western Sahel (10 to 18°N, 

17.5°W to 20°E), there are still discrepancies between the models: some projecting a 

significant drying (e.g., Hulme et al., 2001; Jenkins et al., 2005) and others simulating a 

progressive wetting with an expansion of vegetation into the Sahara (Brovkin, 2002; 

Maynard et al., 2002; Claussen et al., 2003; Wang et al., 2004; Haarsma et al., 2005; 

Kamga et al., 2005; Hoerling et al., 2006).” 

These examples demonstrate that the IPCC both cited Hulme et al. (2001) and transparently 

discussed the complexity of Africa’s climate and the uncertainty in African climate projections. 

This treatment is appropriate and reasonable, contrary to the petitioner’s implication. 

32 
Even in light of the complexities and uncertainties, Hulme et al. (2001) state that a “warming 

climate will nevertheless place additional stresses on water resources [in Africa], whether or not 

future rainfall is significantly altered” and they project reduced precipitation over Tunisia. 

Hulme et al. (2001) do not, however, provide projections for changes in cereal yields (from 

changes in rain-fed agriculture), so their results cannot be compared directly with Agoumi (2003) 

or its supporting documents (discussed in Response 2-12). 

Overall, the IPCC does not ignore either the Parry et al. (2005) or Hulme et al. (2001) studies. 

The findings of these studies, while not directly comparable with Agoumi (2003), are broadly 

consistent. Hulme et al. (2001) project increased drying over northern Africa while Parry et al. 

(2005) project an increased risk of reduced cereal yields over all of Africa. The petitioner’s claim 

that IPCC was not careful or acted inappropriately in this regard is not confirmed by careful 

review of the material. 

2.1.8 Summary 

The small number of real or alleged errors in the IPCC report is not materially relevant for 

EPA’s Endangerment Finding. Neither of the two errors that are verifiable (the percentage of the 

Netherlands below sea level and the projections for Himalayan glaciers) is relevant to the United 

States and neither is contained within EPA’s endangerment record. Although it is unfortunate 

when any error occurs, two errors in a nearly 3,000-page study are not evidence of a complete 

breakdown of the IPCC’s review process, contrary to petitioners’ suggestions. 

The remaining alleged errors or unsupported statements have not been shown to be erroneous 

and can be traced to findings in the gray literature from which they were derived. As discussed 

further in Subsection 2.2.4.4 in this volume and previously in Volume 1 of the RTC, the IPCC 

provides guidance on how and when to use gray literature, and petitioners do not demonstrate 

that the guidance was not followed. There is no de facto assumption that all gray literature is 

incorrect or suspect, and an examination of the instances raised by petitioners demonstrates that 

the specific allegations of petitioners are unfounded. Furthermore, the statements at issue drawn 

from the gray literature have no material relevance to conclusions supporting EPA’s Findings, as 

explained in RTP Subsection 2.1.1. 

In conclusion, the evidence cited by petitioners does not undermine the overall credibility and 

reliability of the scientific conclusions relied upon and underlying EPA’s Endangerment Finding. 

33 
2.2 Claims That the IPCC Has a Policy Agenda and Is Not Objective and Impartial 

2.2.1 Overview 

Several petitioners argue that the e-mails from the University of East Anglia’s Climatic Research 

Unit (CRU), and other information that has arisen since publication of the Endangerment 

Finding, show that a select group of influential authors who wrote, contributed to, or reviewed 

parts of IPCC assessment reports (or the studies on which the assessment reports were based) 

were not objective and impartial while developing the reports. Several petitioners also argue that 

the CRU e-mails confirm that the IPCC and some of its authors and reviewers have a policy 

agenda and are tailoring the science to suit that agenda. The petitioners allege that the e-mails 

show that the peer-review and report development processes employed by the IPCC are 

“fundamentally corrupt,” lack scientific integrity, are policy prescriptive, and do not yield “true” 

consensus conclusions regarding the state of the science. The petitioners request that EPA 

reconsider its reliance on the IPCC assessment reports that were used as the basis for the 

Endangerment Finding. 

As discussed in detail below, after reviewing the petitioners’ arguments, EPA finds that the 

evidence and arguments provided by petitioners do not support their conclusion that the peerreview and assessment report processes employed by the IPCC were “fundamentally corrupt” 

and policy prescriptive. Further, the petitioners’ arguments, which for the most part rely on 

selective use of the CRU e-mails, misinterpretations of the e-mails, and quotations from press 

articles, do not show that either the IPCC peer-review and report development processes were 

inadequately designed or that they were not implemented properly. We note that several of the 

petitioners’ arguments are not new; many of these comments were submitted and responded to in 

the process of developing the Findings. 

2.2.2 Background 

Several petitioners criticize the IPCC’s report development and peer-review procedures. We 

respond specifically to each allegation in the sections that follow. EPA received similar 

comments during notice and comment on the Endangerment Findings. In Volume 1 of the RTC 

document, we responded in detail to these comments, describing the IPCC’s report development 

and peer-review procedures. However, to provide context for evaluating the merit of these more 

recent allegations, in this background section we revisit the structure and procedures employed 

by the IPCC in developing their reports. 

In response to the allegations raised against it, the IPCC released the following statement in 

December 2009 describing their report development process from beginning to end (IPCC, 

2010a). 

The assessment process begins with a Scoping Meeting attended by scientific experts 

whose task it is to outline the report. The IPCC Bureau selects the experts attending the 

Scoping Meeting after an open call for nominations to Governments and IPCC observer 

organizations. The Bureau consists of experts elected by an IPCC Plenary composed of 

all WMO and UNEP member nations. The outline is then approved by Working Group 

34 
Sessions and endorsed by the Plenary. A call for nominations of authors for the report is 

sent out to Governments and observer organizations. The individual Working Group 

Bureaus select the authors for respective contributions to the Assessment Report, 

ensuring that the composition of the author teams reflects a range of views, scientific 

expertise and geographical diversity. Over the ensuing 3-4 years, writing teams 

collaborate on drafting chapters – including four Lead Author meetings, plus chapter 

meetings as necessary. The author teams prepare two externally reviewed drafts and then 

a final version of their respective chapters. All chapters undergo a rigorous writing and 

open review process to ensure consideration of all relevant scientific information from 

established journals with robust peer review processes or from other sources which have 

undergone robust and independent peer review. Additional procedures are provided for 

information found in sources that have not been published or peer-reviewed. In these 

cases, authors and chapter teams should critically assess and review the quality and 

validity of each source before incorporating results. 

 

The First Order Draft is subject to a formal Expert Review, where any expert is 

encouraged to comment on all aspects of the draft, including, but not limited to, issues of 

interpretation, missed literature, and presentation. Author teams must make a written 

response, explaining how they responded to each comment in developing the next draft. 

A Second Order Draft is compiled based on the comments received during the Expert 

Review. This draft undergoes a second combined formal Expert and Government 

Review. Author teams have to react to the second round of review comments as well and 

prepare the final draft, taking into account all the comments received. The entire review 

process is overseen by a team of 2-3 independent Review Editors for each chapter, whose 

role is limited to overseeing the reviews, ensuring the thoroughness of the responses. All 

the AR4 review comments and responses by the author teams are available online (IPCC, 

2006a). 

 

In parallel, the Summary for Policymakers and the Technical Summary are prepared by 

authors selected from chapter writing teams. The Summary for Policymakers and the 

Technical Summary undergo a formal Expert and Government Review and are revised 

based on the review comments. Again, 2-3 Review Editors oversee the review process 

for the Technical Summary. The Summary for Policymakers is then distributed to the 

Governments for final comment. The Summary for Policymakers undergoes a line-byline approval process by Governments during a multi-day meeting. The Governments 

must reach consensus before text is approved. After the Working Group Session 

approves the Summary for Policymakers, the IPCC Plenary then accepts the entire 

underlying Report (including the individual chapters and Technical Summary). 

To ensure objectivity, transparency, and information quality, the IPCC’s report development 

procedures (IPCC, 1999) clearly describe the roles and responsibilities of coordinating lead 

authors, lead authors, contributing authors, expert reviewers, and review editors in report 

development. It states: 

35 
1. LEAD AUTHORS 

Function: 

To be responsible for the production of designated sections addressing items of the work 

program on the basis of the best scientific, technical and socio-economic information 

available. 

Comment: 

Lead Authors will typically work as small groups which have responsibility for ensuring 

that the various components of their sections are brought together on time, are of 

uniformly high quality and conform to any overall standards of style set for the document 

as a whole. 

The task of Lead Authors is a demanding one and in recognition of this the names of 

Lead Authors will appear prominently in the final Report. During the final stages of 

Report preparation, when the workload is often particularly heavy and when Lead 

Authors are heavily dependent upon each other to read and edit material, and to agree to 

changes promptly, it is essential that the work should be accorded the highest priority. 

The essence of the Lead Authors’ task is synthesis of material drawn from available 

literature as defined in Section 4.2.3. Lead Authors, in conjunction with Review Editors, 

are also required to take account of expert and government review comments when 

revising text. Lead Authors may not necessarily write original text themselves, but they 

must have the proven ability to develop text that is scientifically, technically and socioeconomically sound and that faithfully represents, to the extent that this is possible, 

contributions by a wide variety of experts. The ability to work to deadlines is also a 

necessary practical requirement. Lead Authors are required to record in the Report views 

which cannot be reconciled with a consensus view but which are nonetheless 

scientifically or technically valid. 

Lead Authors may convene meetings with Contributing Authors, as appropriate, in the 

preparations of their sections or to discuss expert or government review comments and to 

suggest any workshops or expert meetings in their relevant areas to the Working 

Group/Task Force Bureau Co-Chairs. The names of all Lead Authors will be 

acknowledged in the Reports. 

2. COORDINATING LEAD AUTHORS 

Function: 

To take overall responsibility for coordinating major sections of a Report 

Comment: 

Coordinating Lead Authors will be Lead Authors with the added responsibility of 

ensuring that major sections of the Report are completed to a high standard, are collated 

and delivered to the Working Group/Task Force Bureau Co-Chairs in a timely manner 

and conform to any overall standards of style set for the document. 

Coordinating Lead Authors will play a leading role in ensuring that any crosscutting 

scientific or technical issues which may involve several sections of a Report are 

addressed in a complete and coherent manner and reflect the latest information available. 

36 
The skills and resources required of Coordinating Lead Authors are those required of 

Lead Authors with the additional organizational skills needed to coordinate a section of a 

Report. The names of all Coordinating Lead Authors will be acknowledged in the 

Reports. 

3. CONTRIBUTING AUTHORS 

Function: 

To prepare technical information in the form of text, graphs or data for assimilation by 

the Lead Authors into the draft section. 

Comment: 

Input from a wide range of contributors is a key element in the success of IPCC 

assessments, and the names of all contributors will be acknowledged in the Reports. 

Contributions are sometimes solicited by Lead Authors but unprompted contributions are 

encouraged. 

Contributions should be supported as far as possible with references from the peer 

reviewed and internationally available literature, and with copies of any unpublished 

material cited; clear indications of how to access the latter should be included in the 

contributions. For material available in electronic format only, the location where such 

material may be accessed should be cited. Contributed material may be edited, merged 

and if necessary, amended, in the course of developing the overall draft text. 

4. EXPERT REVIEWERS 

Function: 

To comment on the accuracy and completeness of the scientific/technical/socio-economic 

content and the overall scientific/technical/socio-economic balance of the drafts. 

Comment: 

Expert reviewers will comment on the text according to their own knowledge and 

experience. They may be nominated by Governments, national and international 

organizations, Working Group/Task Force Bureau, Lead Authors and Contributing 

Authors. 

5. REVIEW EDITORS 

Function: 

Review Editors will assist the Working Group/Task Force Bureau in identifying 

reviewers for the expert review process, ensure that all substantive expert and 

government review comments are afforded appropriate consideration, advise lead authors 

on how to handle contentious/controversial issues and ensure genuine controversies are 

reflected adequately in the text of the Report. 

Comment: 

There will be one or two Review Editors per chapter (including their executive 

summaries) and per technical summary. In order to carry out these tasks, Review Editors 

will need to have a broad understanding of the wider scientific and technical issues being 

addressed. The workload will be particularly heavy during the final stages of the Report 

preparation. This includes attending those meetings where writing teams are considering 

37 
the results of the two review rounds. Review Editors are not actively engaged in drafting 

Reports and cannot serve as reviewers of those chapters of which they are Authors. 

Review Editors can be members of a Working Group/Task Force Bureau or outside 

experts agreed by the Working Group/Task Force Bureau. Although responsibility for 

the final text remains with the Lead Authors, Review Editors will need to ensure that 

where significant differences of opinion on scientific issues remain, such differences are 

described in an annex to the Report. Review Editors must submit a written report to the 

Working Group Sessions or the Panel and where appropriate, will be requested to attend 

Sessions of the Working Group and of the IPCC to communicate their findings from the 

review process and to assist in finalizing the Summary for Policymakers, Overview 

Chapters of Methodology Reports and Synthesis Reports. The names of all Review 

Editors will be acknowledged in the Reports. 

In implementing these procedures across the three working groups of the IPCC’s AR4, 1,250 

scientists (450 lead authors and more than 800 contributing authors) from 130 countries served 

as authors and more than 2,500 experts provided over 90,000 review comments. Many 

petitioners specifically critique the practices employed by IPCC Working Group I, for which 

there were 152 lead authors and 26 review editors from 32 countries, in which 6,000 peerreviewed publications were cited, for which 625 experts from 42 countries provided over 30,000 

review comments, and for which the Summary for Policymakers was approved line by line by 

113 countries. Furthermore, the petitioners specifically critique the practices employed by 

Chapter 6 (Jansen et al., 2007) authors and reviewers of Working Group I, which had two 

coordinating authors and 14 lead authors from 12 countries, 33 contributing authors from nine 

countries, and two review editors who oversaw the handling of more than 2,900 comments from 

the rounds of expert and governmental review. The petitioners also critique the practices 

employed by Chapter 9 (Hegerl et al., 2007) authors and reviewers of Working Group I, which 

had two coordinating authors and seven lead authors from nine countries, 44 contributing authors 

from 12 countries, and three review editors who oversaw the handling of about 2,600 comments 

from the rounds of expert and governmental review. 

The IPCC processes have been developed for the express purpose of ensuring integrity and 

avoiding any possibility of bias in the conclusions drawn from the scientific literature. The level 

of detail and clarity of the requirements—especially concerning report review, the specific 

responsibilities of review editors to assess the quality of author responses to comment, and the 

transparency of the record of comments and responses—provide the foundation for ensuring that 

the reports are credible and sound. 

The IPCC’s peer-review and report development processes are very important components of the 

overall integrity, quality, transparency, and objectivity of its reports. As stated in the TSD (U.S. 

EPA, 2009) for the Endangerment Finding, EPA relied on the assessment literature because: 

they 1) are very recent and represent the current state of knowledge on GHG emissions, 

climate change science, vulnerabilities, and potential impacts; 2) have assessed numerous 

individual, peer-reviewed studies in order to draw general conclusions about the state of 

science; 3) have been reviewed and formally accepted, commissioned, or in some cases 

38 
authored by U.S. government agencies and individual government scientists; and 4) they 

reflect and convey the consensus conclusions of expert authors. 

Finally, we note the following recent IPCC statement regarding their report development 

process: 

The IPCC procedures, which are regularly reviewed and amended by the IPCC members, 

have served the international community effectively for over 20 years. The conclusions 

of the IPCC assessment reports, and especially the Fourth Assessment Report, are as 

solid as careful science can make them. They reflect the current state of knowledge about 

one of the most complex and important of all topics -- climate change science (IPCC, 

2010b). 

2.2.3 Responses to Arguably New Objections Raised by the Petitioners 

The petitioners submit four arguably “new” objections along with excerpts from the CRU emails related to: 1) authorship and reviewer roles among IPCC personnel; 2) an e-mail allegedly 

showing that IPCC authors were aware that citing their own papers could be seen as using the 

IPCC process to advance their own views rather than to present a neutral overview of the 

science; 3) allegations that the IPCC is a biased organization, including claims that IPCC lead 

authors encouraged other authors to focus on policy-prescriptive science; and 4) allegations that 

IPCC authors forced consensus and altered the contents of the assessment reports to eliminate 

any suggestion of non-consensus. We respond to each of these allegations in the subsections 

below. 

2.2.3.1 Allegations of Inappropriate Authorship and Reviewer Roles Among IPCC 

Personnel 

Comment (2-16): 

Peabody Energy argues that the CRU e-mails show inappropriate authorship roles in the 

development of Chapter 6 (“Paleoclimate”) of Working Group I’s contribution to AR4 (Jansen et 

al., 2007). The petitioner alleges that Michael Mann (Penn State) and Thomas Crowley 

(University of Edinburgh) contributed significantly to the development of the chapter, but were 

not listed as contributing authors. In addition, the petitioner alleges that Mann and Crowley were 

inappropriately given the opportunity to comment on drafts of the chapter outside the formal 

review process, thereby compromising their objectivity as reviewers and introducing bias to the 

chapter development process. 

Response (2-16):

EPA has reviewed the petitioners’ submissions and finds that the evidence and arguments they 

provide do not support the conclusions they draw. The content of the e-mails does not show that 

Michael Mann or Thomas Crowley contributed substantially to the writing or key development 

decisions of Chapter 6 (Jansen et al., 2007), or that they introduced any bias. Chapter 6 assesses 

paleoclimatic data and knowledge of how the climate system changes over inter-annual to 

millennial time scales and how well these variations can be simulated with climate models. 

39 
 On December 23, 2004, Michael Mann wrote to Keith Briffa (Chapter 6 lead author) and 

stated, “Thanks again for your phone call, and the (informal) opportunity to help out 

where I can. I’m perfectly happy in that role (as an informal contributor and a formal 

reviewer, for example), if you and Peck, for example, are both comfortable with that.” 2

 

He also sent some website links regarding arguments that some have made against his 

work. In a follow-up e-mail that same day3

, Mann again writes to Briffa, stating “I went 

ahead and tried to make some constructive comments on what you sent...Let me say I 

think it’s shaping up very nicely--looks like it should be a significant improvement on the 

‘01 report. You’ve handled the various controversies and points of dispute delicately and 

adeptly...I made a dozen or so minor comments--please make use of them as you see 

fit...Thanks again for including me in and giving me an opportunity to comment.” 4 

These e-mails show that Mann served as an informal contributor on a preliminary draft of 

Chapter 6 (Jansen et. al, 2007), and the IPCC’s response to comments document for 

Chapter 6 confirm that Mann was also a formal reviewer (IPCC, 2006a). The petitioners 

allege that Mann could not have objectively reviewed the chapter if he also provided 

information for its development, but these e-mails do not show that Mann “significantly 

contributed” to the development of this chapter. In fact, the evidence provided by the 

petitioner indicates that Mann participated at most in a limited way as an informal 

contributor, providing a small amount of information, such as Web links, to the authors. 

This level of involvement would not warrant being listed as a contributing author, as 

Mann was involved neither with assessing the underlying literature nor with writing text 

for the chapter. The IPCC does not require informal contributors of this nature to be 

acknowledged as authors in the final report. There is no basis to conclude that listing him 

as an author would have changed the content or conclusions of the chapter in any way. 

There is also no basis to conclude that his comments were biased or lacked objectivity, or 

that the resulting chapter was biased or lacked objectivity. The fact that Mann provided 

the Chapter 6 authors with a limited amount of information does not mean that his 

objectivity was compromised during the formal review process. Petitioners appear to 

conclude otherwise, but nothing they provide supports drawing such a broad conclusion. 

Finally, we note that the petitioner does not provide any examples of Mann’s review 

comments on this chapter that they claim demonstrate bias or lack of objectivity. 

 Several e-mails from June and July of 2005 (e-mail files 1122300990.txt5

, 

1121869083.txt6

, and 111886641.txt)7 show that Thomas Crowley was consulted by 

Keith Briffa and Jonathan Overpeck (Chapter 6 coordinating lead author) regarding a 

medieval warming figure that Crowley had been developing, which Briffa and Overpeck 

 

3

 E-mail file 1102956436.txt, (December 13, 2004), page 763, line 13 of PDF version entitled: CRU Emails 1996-

2009.pdf 

3

 E-mail file 1103828684.txt, (December 23, 2004), page 771, line 37 of PDF version entitled: CRU Emails 1996-

2009.pdf 

4

 E-mail file 1103828684.txt, (December 23, 2004), page 771, line 37 of PDF version entitled: CRU Emails 1996-

2009.pdf 

5

 E-mail file 1122300990.txt, (July 25,2005), page 952, line 33 of PDF version entitled: CRU Emails 1996-2009.pdf 6

 E-mail file 1121869083.txt, (July 20,2005), page 916, line 42 of PDF version entitled: CRU Emails 1996-2009.pdf 7

 E-mail file 1118866419.txt, (June 15,2005), page 889, line 32 of PDF version entitled: CRU Emails 1996-2009.pdf 

40 
were possibly interested in using for Chapter 6. There is no evidence in the e-mails that 

Crowley helped write or develop the chapter in any other capacity. In fact, the e-mails 

simply document an interaction between the lead authors and Crowley, in which the 

authors are seeking clarification regarding a particular figure. Such inquiries are 

completely appropriate and in no way compromise the objectivity and credibility of that 

chapter’s development. It appears that Crowley provided useful background and advice 

on the use of his figure, and the e-mails provide no support that he contributed significant 

text or had any editorial power over the chapter. 

Given the technical nature of this field of climate science, it is reasonable and expected 

that IPCC authors might require detail or clarification regarding some of the underlying 

studies. Therefore they might need to consult the authors of specific studies to better 

understand how the results were achieved or to ask questions regarding how the data 

were applied, as was the case in this situation. Petitioners have not explained how the 

mere fact that this type of correspondence occurred between Crowley and 

Briffa/Overpeck lead to the conclusion that bias was introduced to the chapter 

development process. The evidence provided by the petitioner does not support this 

argument. 

 In the same set of e-mails, Crowley also states, “I am not sure whether it is wise to add 

me to the CA [contributing author] list, just because the reviewer is supposed to be 

impartial and a CA loses that appearance of impartiality if he has now been included as a 

CA - may want to check with Susan S. on this one to be sure - still happy to provide 

advice.” The petitioner alleges that Crowley’s e-mail signifies that he knew of the risk of 

compromising objectivity and did so anyway by both contributing significantly to the 

chapter’s development and being an expert reviewer. The evidence provided by the 

petitioner does not show that Crowley participated in any manner beyond having a 

limited role in answering questions concerning a figure he had developed, or that his 

doing so compromised his objectivity as a reviewer. The petitioners do not, for example, 

provide any examples of his review comments on this chapter that they claim 

demonstrate bias or lack of objectivity. As stated above, IPCC does not require informal 

contributors to be acknowledged in the final report. The petitioners’ evidence does not 

show that Crowley’s informal contribution and correspondence with the Chapter 6 

authors led to improper and erroneous changes or conclusions in the report. Furthermore, 

after the exchange of these e-mails, Overpeck wrote: “Thanks for moving this forward 

and making sure we do it right (i.e., without any bias, or perception of bias)”.8

 This 

demonstrates that the coordinating lead author understood IPCC’s guidelines, ensured 

that they were properly implemented, and therefore avoided any lack of or lapse in 

objectivity. 

The petitioner draws broad conclusions from these e-mails about the intentions of the authors 

and the content of the IPCC chapters, in an attempt to discredit overall the chapter development 

and review processes of the IPCC, and implicitly the IPCC reports themselves. However, the emails cited show that Mann and Crowley had very limited, informal roles in the chapter and the 

 

8

 E-mail file 1121869083.txt, (July 20, 2005), page 918, line 8 of PDF version entitled: CRU Emails 1996-2009.pdf 

41 
e-mails provide no evidence to support assertions of bias or a lack of objectivity. The 

interactions that occurred are allowable under IPCC procedures, and petitioners have not 

demonstrated that the events in question changed the content or conclusions of the chapter in any 

way. 

The Muir Russell investigative panel summarized information Briffa gave them on this issue, 

describing Briffa as having said (Russell, 2010): 

There is no proscription in the IPCC rules to prevent the author team seeking expert 

advice when and where needed. The Technical Support Unit (TSU) and the CLAs of 

Chapter 6 agree that the author team was allowed to seek such advice. Copies of 

communications from both CLAs (Jansen and Overpeck) and the IPCC WG1 TSU are 

provided by Briffa (and published on the website) to provide support to Briffa’s claim 

that his actions did not contravene IPCC procedures. 

Even if the petitioner’s allegations that Mann and Crowley “significantly contributed” to the 

development of Chapter 6 were true—which we do not believe to be the case—and even if this 

contribution were atypical, this does not lead to the conclusion that the scientific integrity of the 

conclusions from the chapter was compromised. The evidence provided by petitioners does not 

indicate errors or significant changes that resulted from involvement of these persons, and does 

not demonstrate that the final product was either inaccurate or lacked impartiality, nor does the 

petitioner to any such result. We find that Chapter 6 was developed in an objective manner, is 

accurate, and represents the best available scientific information. 

Comment (2-17): 

Peabody Energy argues that the CRU e-mails show that IPCC lead authors “viewed their work as 

advocacy, rather than scientific analysis, which could be marshaled against opponents.” In 

support of this argument, the petitioner provides a February 2005 e-mail from Michael Mann to 

Phil Jones, which states “I saw the paleo draft (actually I saw an early version, and sent Keith 

some minor comments). It looks very good at present--will be interesting to see how they deal 

w/ the contrarian criticisms--there will be many. I’m hoping they’ll stand firm (I believe they 

will--I think the chapter has the right sort of personalities for that).” 

Response (2-17):

The petitioner’s interpretation of the e-mail statement is unfounded. The e-mail from Michael 

Mann9

 describes his reaction to a preliminary draft of a Medieval Warm Period (MWP) section 

of Chapter 6 (“Palaeoclimate”) of Working Group I’s contribution to the AR4 (Jansen et al., 

2007). First, it is important to note that Michael Mann and Phil Jones were neither lead nor 

contributing authors for Chapter 6, as the petitioner implies. Therefore, any allegations that 

Mann and Jones used their authorship authority to advocate against critics of Chapter 6’s 

findings are unfounded. For our response to allegations that Michael Mann had a significant role 

in the development of Chapter 6, please see Response 2-16 in this section. Moreover, the e-mail 

does not support the petitioner’s allegation that Mann and Jones were viewing their work as 

“advocacy” to use “against opponents.” Rather, Mann is simply stating his opinion regarding 

 

9

 E-mail file 1107454306.txt, (Feb. 3, 2005), page 821, line 44 of PDF version entitled: CRU Emails 1996-2009.pdf 

42 
how the paleoclimate chapter should be written and that he looked forward to seeing how the 

Chapter 6 authors dealt with criticisms. At no point does Mann suggest that the scientific 

findings be manipulated to support a pre-determined view. It is clear that he is merely 

expressing his hope for how the authors will respond to comments they (not Mann) are tasked 

with addressing. 

Comment (2-18): 

The State of Texas argues that the IPCC scientists who wrote the CRU e-mails “wielded 

tremendous authority over the IPCC.” In support of their argument, the petitioners state, “For 

example, AR4 cites Dr. Jones’s work 38 times in 21 chapters of two Working Groups, Mann is 

cited 27 times in 7 chapters of two Working Groups, Briffa is cited 23 times in 9 chapters of two 

Working Groups, Wigley is cited 66 times in 18 chapters of all three Working Groups, Overpeck 

is cited 15 times in 5 chapters of two Working Groups, Osborn is cited 30 times in 10 chapters of 

two Working Groups, Trenberth is cited 58 times in 18 chapters of two Working Groups, and 

Santer is cited 26 times in 8 chapters of two Working Groups, just to name a few.” The 

petitioner goes on to argue that “Thus, to the extent their objectivity, impartiality, truthfulness, 

and scientific integrity are compromised or in doubt, so too is the objectivity, impartiality, 

truthfulness, and scientific integrity of the IPCC report, the CRU temperature data, the NOAA 

[National Oceanic and Atmospheric Administration] temperature data, and other scientific 

research that is shown to have relied on their compromised research.” 

Response (2-18):

Many of the scientists who wrote the CRU e-mails were and still are important figures in the 

field of climate change science. It is important to note that the statistics provided by the 

petitioner regarding how frequently the studies of these scientists (e.g., Phil Jones and Michael 

Mann) were cited in AR4 are neither surprising nor unreasonable. The IPCC AR4 (IPCC, 

2007a) cited over 18,000 peer-reviewed studies. Therefore these statistics (e.g., “Wigley is cited 

66 times in 18 chapters of all three Working Groups, Overpeck is cited 15 times in 5 chapters of 

two Working Groups”) do not support the petitioner’s allegation that these studies were cited too 

frequently and that these scientists therefore “wielded tremendous authority over the IPCC.” 

These scientists are some of the most well-published climate scientists in the world, and their 

work was synthesized across the three Working Group reports of the AR4. We conclude that 

these facts by themselves demonstrate nothing other than the fact that the IPCC, as intended, is 

assessing available, peer-reviewed literature. The simple fact that these individuals are wellpublished and that their studies are cited in AR4 does not imply “tremendous authority.” The 

petitioner provided no additional evidence to support their allegation. 

As explained in Section 2.2.2 (Background) of this Volume, over 1,250 scientists from 130 

countries served as authors for the AR4. It was these hundreds of authors who had the authority 

to assess the available literature, summarize the state of the science, and reference the studies in 

the AR4. The IPCC has robust procedures to ensure that the assessment reports are objective, 

unbiased, and represent the state of the science regarding climate change. These procedures 

include processes to ensure that no one individual or group of individuals exerts disproportionate 

influence in developing any piece of the assessment reports. Further, as addressed in the specific 

responses in Section 2.2.3.1 of this Volume, the evidence provided by the petitioners does not 

show that these procedures were flawed or improperly implemented. For more information on 

43 
these procedures, please see Volume 1, Section 1, of the RTC document and this section (2.2) of 

the RTP document. 

The mere fact that someone is frequently cited is also not evidence for the petitioners’ argument. 

The petitioner must also demonstrate that the referenced literature is biased or flawed, which 

they have not done, as compared to the straightforward view that the studies produced by these 

scientists are very robust and of high quality. The petitioner is making allegations without giving 

due regard for the content of the actual science, which we thoroughly reviewed in the 

Endangerment Finding’s RTC documents and again in the response to both the new and 

previously submitted comments of the petitioners. 

Please see the Denial and Volume 1 of the RTP document for our response to specific allegations 

regarding what the CRU e-mails mean for the objectivity and integrity of the IPCC assessments, 

the CRU temperature data, the NOAA temperature data, and other research that is based on this 

information. 

Comment (2-19): 

Peabody Energy argues that “An IPCC chapter author should not peer review journal articles that 

he intends to include in his chapter because of the clear conflict of interest. The chapter author is 

supposed to be providing a neutral summary of the science, not advancing his own view of the 

science. If the chapter author reviews papers that are then included in his chapter, he could be 

seen as advancing his own agenda both in his review of the paper and its selection for inclusion 

in the IPCC report.” To support their argument, the petitioner provides a July 2005 e-mail from 

Phil Jones to John Christy that states, “I am reviewing a couple of papers on extremes, so that I 

can refer to them in the chapter for AR4. Somewhat circular, but I kept to my usual 

standards”10. The petitioner goes on to state that “Jones reviewed papers so that he could get 

them published and therefore could refer to them in AR4 Chapter 3. The petitioner concludes 

that “this is indeed ‘circular’ and violates his supposed neutrality both as an AR4 author and as

reviewer of the paper.” As additional support, Peabody Energy references another e-mail dated 

May 20, 2005, from Phil Jones to Michael Mann regarding Jones’ review of a temperature 

reconstruction paper for Climatic Change.

 a 

 papers that he favored.” 

11 The petitioner states: “One wonders just how 

unbiased Jones’ review of this paper really was, particularly in light of Jones’ admission that he 

applied less than stringent review standards to

Response (2-19): 

First, we find it unconvincing and unclear why, according to the petitioner, an author of an IPCC 

chapter should not serve as a peer reviewer of a journal paper that in turn may be incorporated 

into that IPCC chapter. Thus, we disagree with the petitioner’s allegations that Phil Jones 

introduced bias and reviewed these papers unobjectively in an effort to advance his own views of 

the science. Jones did not appoint himself to review the papers for the journals, but was selected 

 

10 E-mail file 1120593115.txt, (July 5, 2005), page 906, lines 21-22 of the PDF version entitled: CRU Emails 1996-

2009.pdf 

11 E-mail file 1116611126.txt, (May 20, 2005), page 882, line 45 of the PDF version entitled: CRU Emails 1996-

2009.pdf 

44 
by an independent editor to be a reviewer based on his experience and expertise related to 

climate science. Since Jones is well-published and a prominent paleoclimate scientist, it is 

reasonable and logical to conclude that the editor who chose him was aware of his work on the 

AR4 and judged that it was not an inherent conflict of interest. In addition, Jones would not have 

been the only reviewer for those studies. Typically, between two and four independent experts 

are selected to review manuscripts. Therefore, Jones would not have had the authority or power 

to coerce or bias the process to “advance his own agenda.” The petitioner is inferring that Jones 

was trying to do this, but provides no evidence that Jones’ actions resulted in papers being 

unjustly published when they should not have been, or papers being unjustly cited in the AR4 

when they should not have been. 

The petitioner’s claim that an e-mail between Jones and Mann represents an “admission that he 

[Jones] applied less than stringent review standards to papers that he favored” is also 

unsupported by evidence. Rather, the petitioner misinterprets and misrepresents Jones’ e-mail to 

Michael Mann regarding Jones’ review of a temperature reconstruction paper for Climatic 

Change. This e-mail sent on May 20, 2005, reads: 

Mike, 

Just reviewed Caspar’s [Amman, of the National Center for Atmospheric Research] paper 

with Wahl [Eugene Wahl of the National Climatic Data Center] for Climatic Change. 

Looks pretty good. Almost reproduced your series and shows where MM [Steve 

McIntyre, formerly of Northwest Exploration Co., and Ross McKitrick of the University 

of Guelph] have gone wrong. Should keep them quiet for a while. Also they release all 

the data and the R software. Presume you know all about this. Should make Keith’s life 

in Ch 6 easy! Also, confidentially for a few weeks, Christy and Spencer [John Christy 

and Roy Spencer of the University of Alabama in Huntsville] have admitted at the 

Chicago CCSP meeting that their 2LT record is wrong!! They used the wrong sign for 

the diurnal correction! Series now warms - not quite as much as the surface but within 

error bands. Between you and me, we’ll be going with RSS in Ch 3 and there will be no 

discrepancy with the surface and the models. Should make Ch 3 a doddle now! Keep 

quiet about this until Bern at least. Can tell you more then. RSS (Carl Mears and Frank 

Wentz) found the mistake! The skeptic pillars are tumbling! 

Cheers Phil12

Despite the allegations by the petitioner, this e-mail shows no indication that Jones’ review of the 

Ammann and Wahl paper for Climatic Change was biased or that he did not employ rigorous 

standards of objectivity and neutrality in evaluating the merits of the studies. The e-mail simply 

indicates that Jones approved of the findings by the authors and that he found the results to have 

important implications regarding the validity of temperature reconstructions. The petitioner is 

significantly skewing the meaning of these e-mails and misrepresenting what Jones said to infer 

improper conduct in his review of the paper. 

 

12 E-mail file 1116611126.txt, (May 20, 2005), page 882, lines 6-15 of the PDF version entitled: CRU Emails 1996-

2009.pdf 

45 
Finally, the evidence provided by Peabody Energy does not support their allegation that Jones 

was biased or failed to objectively assess the available literature for the AR4 as a result of having 

reviewed these papers. From our review of the evidence, we conclude only that Jones reviewed 

the studies and that he was also an author for Chapter 3 (“Observations: Surface and 

Atmospheric Climate Change”) of Working Group I’s contribution to the AR4 (Trenberth et al., 

2007). For that chapter, over 65 authors from 16 countries were tasked with reviewing and 

assessing the best available science regarding observed climate change and distilling this 

information into key messages that capture the state of knowledge. Once again, Jones would not 

have had the authority or power to coerce or bias the process to “advance his own agenda” by 

developing conclusions that do not represent the state of the science. Chapter 3, like all of the 

AR4, went through multiple rounds of expert and government review, in which more than 3,400 

comments were received and addressed, to ensure that the conclusions accurately represent and 

summarize the best available science. The large number of authors, the multiple rounds of 

expert and government reviews, and the detailed approval process are all deliberate procedures 

developed by the IPCC to ensure that the reports maximize objectivity, credibility, and quality. 

See Section III.A of the Findings, Volume 1 of the RTC document and Section 2.2.2 

(Background) of the RTP document for more information on the IPCC’s report development 

procedures. 

2.2.3.2 Allegations That Citing One’s Own Papers Compromises Objectivity 

Comment (2-20):

Peabody Energy states that IPCC authors cited their own papers extensively in the AR4, which 

invalidates the purpose of these assessment reports, which are designed to objectively look 

across the literature and convey the state of the science. The petitioner cites an e-mail by 

Jonathan Overpeck from June 200513 as evidence that allegedly “reveals that the IPCC authors 

were aware that citing their own papers could be seen as using the IPCC process to advance their 

own views rather than to present a neutral overview of the science.” The petitioner further 

provides a statistic regarding the frequency at which the authors of Chapter 9 of Working Group 

I of AR4 cited their own papers: “About 40% of the papers cited in Chapter 9 were written by 

Chapter 9 authors.” 

Response (2-20):

It should come as no surprise that many papers by Chapter 9 authors were cited in the chapter. 

IPCC authors are chosen in part based on their expertise on a particular subject and the degree to 

which they have published recent, high-quality papers in the field. Moreover, in some areas 

(e.g., medieval warming period analysis, ocean acidification), there can be limited studies 

outside the research published by particular scientists, including IPCC authors, on which to base 

summaries of the science. Contrary to the petitioner’s allegations, this does not mean that IPCC 

authors were not providing neutral and objective summaries of the science. In fact, the petitioner 

provides no evidence that the practice of citing one’s own papers led to biased conclusions in the 

AR4. Given the rigor of the IPCC review process, described in Section 2.2.2 (Background) of 

this Volume, it is indeed highly unlikely that an author’s improper citation of his or her own 

work would escape notice. 

 

13 E-mail file 1120014836.txt, (June 28, 2005), page 900, line 32 of the PDF version entitled: CRU Emails 1996-

2009.pdf 

46 
Moreover, the e-mail from Jonathan Overpeck (coordinating lead author of Chapter 6 of 

Working Group I’s contribution to the AR4), does not support the petitioner’s assumption of 

misconduct, and instead shows that Overpeck was encouraging the authors of that chapter to 

minimize citing their own papers to the extent possible, and to only do so when “absolutely 

necessary.” Overpeck’s awareness that the authors “citing their own papers could be seen as 

using the IPCC process to advance their own views rather than to present a neutral overview of 

the science” does not mean that such citation actually was for the alleged improper purpose—

especially when the e-mail demonstrates that Overpeck intentionally took steps to avoid 

impropriety, or even the appearance of impropriety. The evidence provided by petitioners does 

not show that the authors cited their own studies in order to advance their own policy views; in 

fact, it shows they were cautioned to avoid citing their own studies except where absolutely 

necessary and appropriate. The full text of Overpeck’s e-mail is provided here: 

Hi all - thanks Fortunat and Stefan for more debate on the 1470. Sounds like the final 

decision is up to Eystein, but I can guess the way he’s thinking. With regard to refs - 

remember that our goal is to cut the number of references significantly. Since this is an 

assessment and not a review, we can delete all but the most recent and comprehensive 

references. I don’t like cutting out the original refs any more than you, but we just don’t 

have room, and its more important to have text than exhaustive references. Our 

colleagues will hopefully understand, and if they don’t then they need to do an ego check. 

It’s more important that we make an impact with policy makers rather than with citation 

indices. Does this make sense? In any case, please help make sure we trim the total 

references DOWN in number by a significant number. This is not happening [to] the 

degree it should. Also, please not[e] that in the US, the US Congress is questioning 

whether it is ethical for IPCC authors to be using the IPCC to champion their own 

work/opinions. Obviously, this is wrong and scary, but if our goal is to get policy makers 

(liberal and conservative alike) to take our chapter seriously, it will only hurt our effort if 

we cite too many of our own papers (perception is often reality). PLEASE do not cite 

anything that is not absolutely needed, and please do not cite your papers unless they are 

absolutely needed. Common sense, but it isn’t happening. Please be more critical with 

your citations so we save needed space, and also so we don’t get perceived as self serving 

or worse. Again, we can debate this if anyone thinks I’ve gone off the deep end. 

Thanks, peck 

PS - this is not to say anything critical of the refs Fortunat is suggesting - we must cite the 

most relevant papers, and we must be as up to date as possible.14 

Regarding the statistics submitted, the petitioner has not provided any evidence that the Chapter 

9 authors cited their own studies more frequently than would be appropriate given the number of 

peer-reviewed and published studies on this particular climate science topic (understanding and 

attributing climate change in the case of Chapter 9), and the statistics alone, without context, 

prove nothing. More than 50 authors from 15 different countries contributed to the development 

of Chapter 9. Given the large number of perspectives and the wide-ranging expertise of this 

group, it is not surprising that 40% of the papers were written by the chapter’s authors. Contrary 

 

14 E-mail file 1120014836.txt, (June 28, 2005), page 901, line 13 of the PDF version entitled: CRU Emails 1996-

2009.pdf 

47 
to the petitioner’s allegations, and consistent with the IPCC’s report development guidelines as 

described in Volume 1 of the RTC document, the statistics provided by the petitioner show that 

the most qualified and experienced personnel contributed to the development of this chapter. 

When read in full, Overpeck’s email clearly shows that he was taking deliberate actions to ensure 

that the science was presented in an objective and unbiased manner. 

We note that the petitioners do not provide or reference any studies that they say should have 

been included instead. Importantly, petitioners again fail to show how the allegedly irregular 

practice that they challenge resulted in conclusions that are inaccurate or contrary to the 

consensus science. 

2.2.3.3 Allegations That IPCC Is Biased 

Comment (2-21): 

The Competitive Enterprise Institute, the Southeastern Legal Foundation, the State of Texas, and 

the Ohio Coal Association argue that Jonathan Overpeck, the coordinating lead author for 

Chapter 6 (“Palaeoclimate”) of Working Group I’s contribution to the AR4, encouraged 

contributing authors to focus on findings that are most policy relevant (thereby, according to the 

petitioners, “supporting preconceived” assessments of the science), and that he did not encourage 

open and neutral presentations of the science. The petitioners draw this conclusion from an email written by Overpeck and Eystein Jansen (the other coordinating lead author) to the lead and 

contributing authors for Chapter 6, which states, “With respect to text, try hard to get it down to 

size, and to ensure that it is FOCUSED on only that science which is policy relevant. ALL 

TEXT should support an Exec Summary Bullet”15. 

 

15 E-mail file 1121392136.txt, (July 14, 2005), Page 912, Line 35 of PDF version entitled: CRU Emails 1996-

2009.pdf. 

48 
Response (2-21):

The Overpeck/Jansen e-mail to Chapter 6 authors indicates that he encouraged them to focus on 

the findings that are most policy relevant. However, “policy relevant and compelling” does not 

mean or imply “policy prescriptive,” as alleged by the petitioners. “Policy relevant” means the 

neutral and objective presentation of scientific, technical, and socio-economic factors that are 

relevant to the issues or policies that policymakers care about. This is to be contrasted with other 

issues that are less relevant to policymakers and thus less appropriate for these types of 

assessment reports, which aim to objectively and thoroughly synthesize scientific information to 

support development of informed policies. “Policy relevant” is completely different from 

“policy prescriptive,” which refers to the presentation of scientific information with the aim of 

advancing a particular public policy agenda. 

The e-mail from Overpeck and Jansen does not support petitioners’ conclusion that they were 

being policy prescriptive. There is no indication that authors were encouraged to limit their 

contributions only to findings that supported a particular policy agenda. Rather, it shows the 

opposite: they were encouraged to avoid this and to provide policy relevant information that 

would be of use to policymakers as they consider the various possible policies. We further note 

that the petitioners do not identify information in Chapter 9 that is “policy prescriptive,” or 

provide any information on what policies Overpeck and Jansen were purportedly advancing. 

As the IPCC clearly states on its website regarding its mission statement, the organization 

reviews and assesses the most recent scientific information to produce assessment reports that 

are “policy relevant and policy neutral, never policy prescriptive” (IPCC, 2010c). The 

petitioners’ evidence does not show that the IPCC failed to execute this very important principle. 

The petitioners’ allegations and implications do not call into question the integrity of these IPCC 

authors. Finally, we note (as described in Volume 1 of the RTC document) that the official 

expert and government reviews of the summary for policymakers for each working group (IPCC, 

2007c, 2007d, 2007h) further ensure that the reports are not policy prescriptive. 

Comment (2-22): 

Peabody Energy argues that the contents of several CRU e-mails from August 200516 between 

Jonathan Overpeck, Tim Osborn, and Keith Briffa show that the authors for Chapter 6 of 

Working Group I’s contribution to the AR4 (Jansen et al., 2007) were focusing not on the 

presentation of “neutral science” but rather on “presenting a strong case.” 

Response (2-22): 

The full content of the e-mails at issue is important for understanding what the authors were 

actually saying. 

 

16 E-mail file 1123268256.txt, (August 5, 2005), page 963, line 29 of PDF version entitled: CRU Emails 1996-

2009.pdf; e-mail file 1123513957.txt, (August 8, 2005), page 964, line 25 of PDF version entitled: CRU Emails 

1996-2009.pdf 

49 
E-mail from Overpeck to Osborn and Briffa on Monday, August 5, 2005

Hi Tim and Keith - Hope you’re not going to kill me, but I was talking with Susan 

Solomon today, and she impressed me with the need to make several points if we can. 

One issue (other to come in a subsequent email) is whether we can extend the MWP box 

figure to include the 15th century. I don’t read the blogs that regularly, but I guess the 

skeptics are making hay of their being a global warm event around 1450AD. I agree w/ 

Susan that it is our obligation to weigh in on issues like this, so.... can we extend the fig 

to extend up to 1500AD? Sorry about this, Tim. Of course we need it yesterday. Thanks 

x10**6 best, peck17

E-mail from Osborn and Briffa to Overpeck on Monday, August 8, 2005

Hi Peck, there is a period around 1400 AD when the proxy records we’ve used in this 

MWP figure do indicate a warm period - and all records show positive anomalies at the 

same time. Thus it couldn’t/shouldn’t be dismissed in the same way as the MWP, as a 

period of disparate regional behaviour, albeit with more records showing warming than 

cooling. For 1400, all indicate warming but with smaller magnitude than the 20th 

century. If the figure were extended to cover the 15th century, then it would also seem 

necessary to extend it to the present so that the 1400 period could be compared with the 

20th century. I’ve attached 3 versions of the figure. 850-1350 as originally sent. 850-

1500 showing warm anomaly in 1400, but cannot tell how warm relative to present-day. 

850-2000 showing 1400 was not as anomalous as present-day. Take your pick, Peck! 

Cheers Tim and Keith18

E-mail from Overpeck to Osborn and Briffa on Monday, August 8, 2005

Hi Tim - Decisions, decisions... thanks so much for taking the initiative. I think - for the 

reason you state, we should go for the one that includes the 20th century. We make clear 

that these are not reconstructed temp, but normalized anomalies - this keeps us out of 

some trouble. But, I think the main message is that we’re looking at this issue from every 

angle. And, we’re letting others see the issue from every angle. It adds punch. this 

means that the MWP box needs to talk about the period around 1400 - can you make sure 

that’s on Keith’s radar screen. I believe that historians talk about the Medieval Period 

going to at least 1450, so what the heck... I you can adjust the caption to work, and then 

send both it and the final fig to Øyvind, me and Eystein that would be good - make sure 

Keith is ok with it all first, too. Thanks Tim! Best, Peck19

These e-mails describe a conversation between the three scientists in which they are deciding the 

most appropriate timeframe for a particular set of graphics depicting normalized temperature 

anomalies. From our review, the context for the e-mails in question is that Susan Solomon (of 

NOAA, and serving as the co-chair of IPCC Working Group I) wanted to ensure that the views 

 

17 E-mail file 1123268256.txt, (August 5, 2005), page 963, line 29 of PDF version entitled: CRU Emails 1996-

2009.pdf. 

18 E-mail file 1123513957.txt, (August 8, 2005), page 964, line 25 of PDF version entitled: CRU Emails 1996-

2009.pdf. 

19 E-mail file 1123513957.txt, (August 8, 2005), page 964, line 43 of PDF version entitled: CRU Emails 1996-

2009.pdf. 

50 
of various climate change scientists were addressed in AR4. She was clearly trying to 

acknowledge and respond to their concerns, even to the point of reading blogs to better 

understand their arguments when there was no peer-reviewed literature articulating their points. 

In response, Jonathan Overpeck, Tim Osborn, and Keith Briffa discussed a number of options for 

presenting their data on normalized temperature anomalies: first extending the timeline to 1500 

A.D. to address the concerns with data around 1450 A.D., then extending the timeline to the 

present day to provide even more context for these early data. They discussed and ultimately 

decided to modify the graphic to depict the relationship of the MWP to the 20th century because 

that approach would provide important context for understanding current temperature trends, it 

would be “looking at this issue from every angle. And, we’re letting others see the issue from 

every angle.” There is no evidence of bias in this decision. Their presentation of various options 

for the graphic demonstrates their commitment to considering alternative viewpoints and 

thoroughness in assessing the science. The e-mails speak for themselves and show no 

inappropriate behavior among these individuals. We disagree with the petitioner that these emails indicate that the scientists were trying to present science that is not neutral or were 

motivated by a desire to present a “strong case” rather than to present the best science. We 

further note that this graphic went through expert and governmental review and was deemed 

appropriate for inclusion in the IPCC chapter. The petitioner provided no additional evidence 

beyond the text of the e-mails to further justify this allegation. 

Thus, these e-mails do nothing more than indicate that three scientists were trying to present a 

figure that was comprehensive and offered key contextual information on temperature trends 

over the past several centuries. There is nothing inappropriate or biased about that, and the 

petitioner has not provided evidence suggesting that there was. When examined in their full 

context, the e-mails do not indicate any wrongdoing by the three scientists or support the 

petitioner’s claims. 

Comment (2-23): 

In support of their argument that the IPCC is a politicized and biased organization, the 

Competitive Enterprise Institute provided a quote from the Environment Minister of India in 

which he responds to the incorrect IPCC conclusion of disappearing glaciers by announcing that 

India is forming its own independent climate change review panel that will not depend on IPCC 

reports. The Minister stated that “There is a fine line between climate science and climate 

evangelism. I am all for climate science but not for climate evangelism. I think people misused 

the IPCC report” (Indo-Asian News Service, 2010). 

Response (2-23):

See Subsection 2.1.3 in this Volume of the RTP document for EPA’s responses regarding the 

validity of the IPCC’s Himalayan glacier projection and our conclusion that this error does not 

undermine the IPCC’s broader findings and the technical support for endangerment. 

With respect to the implications of the statements from the Indian Environment Minister, Jairam 

Ramesh, they clearly show that he disagreed with the specific IPCC Himalayan glacier 

projection that has been identified as being an error. His statement indicates that he thought that 

the projection was inappropriately developed based on inconclusive science. As described in 

Subsection 2.1.3, the IPCC’s overall assessment of observed glacier loss, projected glacier loss, 

51 
and the impacts of glacier loss on water resources in the Himalayas was not compromised by this 

single faulty projection. Numerous studies cited by the IPCC document a general decline in 

Himalayan glacier mass, project substantial future declines, and discuss the impacts of these 

changes on water resources and society, which is consistent with the conclusions drawn by the 

IPCC. 

The evidence provided by the petitioner appears to mischaracterize the Minister’s position. The 

Minister did not make any statements that support the petitioner’s allegation that the IPCC is 

biased or politicized. Rather, the Minister expressed his disapproval of the incorrect glacier 

projections and stated that India needed to perform its own research related to this issue and 

other climate change impacts in the country. Specifically, the Minister stated (Indo-Asian News 

Service, 2010): 

I respect the IPCC. At the same time India is a large country... we can’t depend only on 

IPCC. So we have launched the Indian Network on Comprehensive Climate Change 

Assessment... It’s got 125 research institutions from across the country. We will have 

international collaborations. It’s a kind of an Indian IPCC and not a rival to the IPCC. 

We will do our own assessment. 

It is not uncommon for countries to undertake their own climate change assessments, and it is 

misleading for the petitioner to imply that the Minister’s statements represent a lack of faith in 

the IPCC. Finally, even if the statements by the Minister were to be stretched and interpreted as 

a comment about the IPCC as a politicized organization, it would be the view of one 

representative of one country and would not represent the official position of the 194 countries 

that participate in the IPCC. The fact that another country chooses to complement the IPCC with 

another assessment process has no implications for the Endangerment Finding. For example, the 

United States has its own climate change science assessment process that is administered by the 

USGCRP, and this body has provided excellent and robust information. 

Comment (2-24): 

The Competitive Enterprise Institute and Ohio Coal Association argue that the IPCC is “not a 

scientific organization,” that people in the organization realize it is not, and that the IPCC is a 

political “organization that reviews and reports science that support its goals.” In support of their 

argument, the petitioner provided a quote from The Guardian (a UK newspaper) which in turn 

quoted Anton Imeson, a former IPCC Working Group II author: 

The Nobel prize was for peace not science ... government employees will use it to 

negotiate changes and a redistribution of resources. It is not a scientific analysis of 

climate change... For the media, the IPCC assessments have become an icon for 

something they are not. To make sure that it does not happen again, the IPCC should 

change its name and become part of something else. The IPCC should have never 

allowed itself to be branded as a scientific organization. 

Response (2-24):

The quote provided by the petitioner comes from a newspaper article in The Guardian (Adam 

and Goldenberg, 2010), not a scientific journal or a comprehensive review of the IPCC. Imeson 

52 
was one of 10 lead authors for Chapter 1 (“Assessment of Observed Changes and Responses in 

Natural and Managed Systems”) of Working Group II’s contribution to the AR4 (Rosenzweig et 

al., 2007). He is presenting an opinion, not a scientific evaluation, and is one of more than 1,250 

authors from 130 countries that wrote the AR4 with him. It appears that Imeson is concerned 

about potential policy implications of the IPCC reports, namely that governments may use the 

IPCC reports to “redistribute resources.” He does not provide a specific scientific critique, but 

rather a critique of how governments and the media characterize the IPCC reports and 

government policy direction. 

The evidence provided by the petitioner does not show that Imeson’s views are shared by other 

IPCC authors. To evaluate the merits and credibility of Imeson’s statements, one must look at 

the principles governing the IPCC’s work, and the organization’s established procedures for the 

preparation, review, acceptance, adoption, approval, and publication of the assessment reports. 

In addition, it is also important to assess how these principles and procedures were implemented 

in developing the AR4. EPA has conducted such assessments; they are described in detail in 

Section III.A of the Findings; Volume 1, Sections 1 and 5, of the RTC document; Appendix A of 

Volume 1 of the RTC document; and this section of the RTP document. Ultimately, one author’s 

sentiments about how the IPCC’s key findings may be used do not provide us with evidence 

indicating wrong-doing. 

Comment (2-25): 

The Southeastern Legal Foundation and the State of Texas argue that since the comment period 

closed, it has been revealed in the press that the chairman of the IPCC, Rajendra K. Pachauri, has 

multiple potential conflicts of interest. As support for their argument, the petitioners reference a 

Daily Telegraph (UK newspaper) article published on December 20, 2009, titled “Questions over 

business deals of UN climate change guru Dr. Rajendra Pachauri” (Booker and North, 2009). 

The article, along with several other newspaper blogs and articles referenced by the petitioners, 

allege that Pachauri’s connections with various corporations, along with consulting services 

provided to some of these companies, have generated conflicts of interest and resulted in biased 

and compromised IPCC reports. The Southeastern Legal Foundation further states: 

It is remarkable how only very recently has the staggering scale of Dr Pachauri’s links to 

so many of these concerns come to light, inevitably raising questions as to how the 

world’s leading “climate official” can also be personally involved in so many 

organizations which stand to benefit from the IPCC’s recommendations. 

Similarly, the State of Texas argues: 

Pachauri’s conflicts of interest weaken the Endangerment Finding. Dr. Pachauri’s 

conflicts of interest indicate that the IPCC is being led toward a conclusion that climate 

change is a dire threat to the planet that must be reversed; a conclusion that would enrich 

Dr. Pachauri and the entities that employ him. Consequently, EPA has relied on an 

assessment that ensures bias and imbalance, a result that EPA claims to want to avoid. 

53 
Response (2-25):

Rajendra Pachauri is the elected, unpaid chairman of the IPCC. The IPCC chairmanship requires 

expertise and experience in climate change science and policy. The chairperson is elected based 

on this level of expertise and experience. As a result, it is difficult to imagine that a qualified 

candidate would not have connections and interactions with various academic, science, political, 

and business communities. Having such connections is not, in and of itself, evidence of conflict 

of interest in the development of the assessment reports. The petitioners insinuate that 

Pachauri’s professional connections with various companies constitute conflicts of interest, yet 

they did not provide any evidence that Pachauri’s outside activities generated conflicts of interest 

or violated any ethics rules of the World Meteorological Organization or the U.N. Environment 

Programme. In fact, in the interest of transparency, Dr. Pachauri has made available his tax 

returns and details regarding the honorariums and payments from his consulting activities. 

Further, it appears that the auditing firm KPMG examined his personal finances and found that 

all such payments were made to The Energy and Resources Institute, an Indian nongovernmental organization chaired by Dr. Pachauri (Harvey, 2010). 

Most importantly, the petitioners’ argument that these consulting activities led to biased, 

imbalanced, and compromised IPCC assessments is completely unsupported by evidence. The 

petitioners do not provide a single example of a scientific conclusion that was somehow 

influenced by Dr. Pachauri’s alleged conflicts of interest. The Endangerment Finding must and 

does rest on strong science, not innuendo and speculation of the sort provided by the petitioners. 

See Sections 2.2.2 and 2.2.3 in this volume of the RTP document, which address our view that 

the IPCC’s procedures are sufficient to ensure that no one individual—including the IPCC 

chairman—or group of individuals can exert disproportionate influence in developing any piece 

of the assessment reports. The IPCC has robust procedures to ensure that the assessment reports 

are objective, are unbiased, and represent the state of the science regarding climate change. 

Thus, EPA has no reason to conclude, and there is no evidence to suggest, that Pachauri’s 

professional connections influenced the IPCC reports in any way. 

 

Comment (2-26): 

The State of Texas argues that EPA’s RTC document insufficiently addressed comments on the 

Administrator’s consideration of studies that disagreed with the assessment literature. 

Specifically, the petitioner stated: 

In response to public comments suggesting that the Administrator should have included 

studies that disagreed with the Endangerment Finding, EPA notes that “IPCC, 

USGCRP/CCSP [the U.S. Global Change Research Program/Climate Change Science 

Program], and NRC [National Research Council] make considerable effort to ensure that 

their assessment reports reflect a balance of perspectives regarding the state of the 

science.” To support that response, EPA quotes a National Academies report noting that 

the NRC screens all “provisional committee members . . . in writing and in a confidential 

group discussion about possible conflicts of interest.... [N]o individual can be appointed 

to serve (or continue to serve) on a committee of the institution used in the development 

of reports if the individual has a conflict of interest that is relevant to the functions to be 

performed.” Thus, EPA identifies the National Academies’ prohibition on conflicts of 

interest as a means of ensuring that the Endangerment Finding is balanced and unbiased. 

54 
Response (2-26):

We responded to this issue in Response 1-2 of Volume 1 of the RTC document, and we find that 

our response to public comments on this issue was sufficient, detailed, and responsive. The 

petitioner misrepresents EPA’s actual response, which we provide again here to put the 

petitioner’s allegation in perspective. 

Comment (1-2):

A number of commenters (3324.1, 3394.1, 3429.1, 3440.1, 3481.1, 3533.1, 3579.1, 

3596.1, 3707.1, 3747.1, 3764.1, 3915, 4509, 5716, 8624, 10197, 10948, and 11335) argue 

that the Administrator did not reference any documents in her decision-making process 

that offered alternative views on the scientific basis for causes of climate change. 

Commenters recommend that EPA provide a more complete discussion of global 

warming science by using information outside the assessment literature, including studies 

that do not support its conclusions and studies submitted to the docket through the public 

comment period for the Proposed Findings. 

Response (1-2):

We disagree that the Administrator did not consider alternative views on climate change 

science and impacts. Such a contention incorrectly implies that all individual studies 

reviewed and incorporated into the assessments of U.S. Global Change Research 

Program (USGCRP), U.S. Climate Change Science Program (CCSP), Intergovernmental 

Panel on Climate Change (IPCC), and National Research Council (NRC) support uniform 

conclusions on the different elements of greenhouse gas (GHG) and climate change 

science, and that the many thousands of studies reviewed and reflected in these major 

assessment works represent a narrow view of GHG and climate change science. In fact, 

these assessment reports look at the range of the scientific literature without “cherrypicking” and it is EPA’s conclusion that by placing primary reliance on the major 

assessment reports, we have ensured that the determinations are based on reports that 

have considered and weighed all views. EPA relied on the major peer-reviewed 

assessment reports in developing the TSD (U.S. EPA, 2009) precisely to avoid an overreliance on and narrow consideration of individual studies and to ensure that the 

Administrator’s decision would be based on a comprehensive assessment of the scientific 

literature. EPA has determined that the approach taken provided the high level of 

transparency and consistency outlined by EPA’s Guidelines for Ensuring and Maximizing 

the Quality, Objectivity, Utility and Integrity of Information Disseminated by the 

Environmental Protection Agency. 

Regarding the recommendation that EPA provide a more comprehensive discussion and 

consideration of global warming science and literature that is representative of 

“alternative views,” we have done this through our review of comments and literature 

submitted, the associated revision of the TSD, and the development of the eleven 

volumes of the Response to Comments document. See Section III.A. of the Findings, 

“The Science on Which the Decisions Are Based,” for our response to comments on the 

use of the assessment literature and previous responses in this section regarding our 

treatment of new and additional scientific literature provided through the public comment 

55 
process. For EPA’s responses to comments and literature provided on specific climate 

science issues in the TSD, please refer to the appropriate Response to Comment volumes. 

Finally, we note that IPCC, USGCRP/CCSP, and NRC make considerable effort to 

ensure that their assessment reports reflect a balance of perspectives regarding the state of 

the science. We note that the CCSP report Guidelines for Producing CCSP Synthesis and 

Assessment Products state that the reports should “identify disparate views that have 

significant scientific or technical support” (CCSP, 2004). We refer commenters to 

Appendix B of this volume for the full listing of these Guidelines. Further, NRC 

(National Academies, 2006) report development procedures state that: 

[C]areful steps are taken to convene [report development] committees that meet 

the following criteria: 

An appropriate range of expertise for the task. The committee must include 

experts with the specific expertise and experience needed to address the study’s 

statement of task. One of the strengths of the National Academies is the tradition 

of bringing together recognized experts from diverse disciplines and backgrounds 

who might not otherwise collaborate. These diverse groups are encouraged to 

conceive new ways of thinking about a problem. 

A balance of perspectives. Having the right expertise is not sufficient for success. 

It is also essential to evaluate the overall composition of the committee in terms of 

different experiences and perspectives. The goal is to ensure that the relevant 

points of view are, in the National Academies’ judgment, reasonably balanced so 

that the committee can carry out its charge objectively and credibly. 

Screened for conflicts of interest. All provisional committee members are 

screened in writing and in a confidential group discussion about possible conflicts 

of interest. For this purpose, a “conflict of interest” means any financial or other 

interest which conflicts with the service of the individual because it could 

significantly impair the individual’s objectivity or could create an unfair 

competitive advantage for any person or organization. The term “conflict of 

interest” means something more than individual bias. There must be an interest, 

ordinarily financial, that could be directly affected by the work of the committee. 

Except for those rare situations in which the National Academies determine that a 

conflict of interest is unavoidable and promptly and publicly disclose the conflict 

of interest, no individual can be appointed to serve (or continue to serve) on a 

committee of the institution used in the development of reports if the individual 

has a conflict of interest that is relevant to the functions to be performed.” 

We refer commenters to Appendix C of this volume for more information on NRC report 

development process. In addition, please see response to comments below regarding the 

IPCC report development process and procedures for ensuring a balance of perspectives. 

Petitioners reference only a small part of our response in their allegations. Our full response and 

the record for the Endangerment Finding demonstrate that the Administrator thoroughly 

56 
considered a range of studies, including those that disagree with the conclusions of the 

assessment literature. 

2.2.3.4 Allegations That IPCC Lead Authors Forced Consensus and Suppressed 

Dissenting Views 

Comment (2-27): 

The Southeastern Legal Foundation, the State of Texas, Peabody Energy, the Competitive 

Enterprise Institute, and the Ohio Coal Association argue that the CRU e-mails (in particular an 

e-mail from Phil Jones to Michael Mann expressing their disapproval of two new studies 

authored by Stephen McIntyre and Ross McKitrick) reveal that the contents of the IPCC reports, 

in this case Chapter 3 of the AR4 Working Group I report (Trenberth et al., 2007), were altered 

to eliminate any suggestion of non-consensus on key issues. Petitioners claim that this occurred 

so as to support a specific policy agenda, and that dissenting views were not given appropriate 

attention and consideration. The petitioners also argue that a group of authors have actively tried 

to suppress external challenges to consensus. 

Response (2-27): 

Although the petitioners draw broad conclusions of unethical and biased conduct from the e-mail 

between Phil Jones and Michael Mann, this e-mail does not show that the two IPCC authors 

acted unethically, or that they took any actions to suppress dissenting views, as alleged by the 

petitioners. The e-mail at issue was sent on July 8, 2008, and states: 

Mike, 

Only have it in the pdf form. FYI ONLY - don't pass on. Relevant paras are the last 2 in 

section 4 on p13. As I said it is worded carefully due to Adrian knowing Eugenia for 

years. He knows the're wrong, but he succumbed to her almost pleading with him to tone 

it down as it might affect her proposals in the future ! I didn't say any of this, so be 

careful how you use it - if at all. Keep quiet also that you have the pdf. The attachment 

is a very good paper - I've been pushing Adrian over the last weeks to get it submitted to 

JGR or J. Climate. The main results are great for CRU and also for ERA-40. The basic 

message is clear - you have to put enough surface and sonde obs into a model to produce 

Reanalyses. The jumps when the data input change stand out so clearly. NCEP does 

many odd things also around sea ice and over snow and ice. The other paper by MM is 

just garbage - as you knew. De Freitas again. Pielke is also losing all credibility as well 

by replying to the mad Finn as well - frequently as I see it. I can't see either of these 

papers being in the next IPCC report. Kevin and I will keep them out somehow - even if 

we have to redefine what the peer-review literature is! 

Cheers Phil20

The e-mail shows that Phil Jones strongly disapproved of the quality of the two studies21 and that 

he did not deem them to be of sufficient quality and credibility for inclusion in an IPCC 

 

20 E-mail file 1089318616.txt, (July 8, 2008), Page 720, Line 46 of PDF version entitled: CRU Emails 1996-

2009.pdf 

21 The paper Jones refers to by “MM” was McKitrick and Michaels (2004). It is not clear what the second paper is, 

however it was possibly De Laat and Maurellis (2006). 

57 
assessment report. In addition, both of the papers were in fact included in the IPCC assessment 

report. The “MM” study (McKitrick and Michaels, 2004) is referenced in the IPCC chapter, and 

assuming that the second study Jones referred to is De Laat and Maurellis (2006), that was 

included as well. This disproves the allegations of the petitioners that this e-mail is evidence that 

dissenting views were suppressed or that the IPCC assessment report was biased by such efforts. 

For example, these two studies are discussed in Chapter 3 (Trenberth et al., 2007): 

McKitrick and Michaels (2004) and De Laat and Maurellis (2006) attempted to 

demonstrate that geographical patterns of warming trends over land are strongly 

correlated with geographical patterns of industrial and socioeconomic development, 

implying that urbanization and related land surface changes have caused much of the 

observed warming. 

Thus, the events surrounding the citation of the McKitrick and Michaels (2004) and De Laat and 

Maurellis (2006) studies provide stronger support for the proposition that the IPCC assessed and 

cited critical literature than for the petitioners’ view that these events demonstrate that the IPCC 

is biased. 

The e-mail between Jones and Mann, which is the only evidence offered by petitioners to support 

this allegation, simply does not show that either 1) the contents of this chapter, let alone all of the 

IPCC assessment reports, were altered to eliminate a suggestion of nonconsensus, or 2) IPCC 

authors actively tried to suppress external challenges to consensus. It is not uncommon for 

scientists to disagree with the work of others, and this e-mail does not provide evidence that Phil 

Jones or any other IPCC author acted unethically or took actions to suppress dissenting views, 

notwithstanding the loose talk in the e-mail. 

Our conclusion regarding this e-mail is consistent with the findings of the Independent Climate 

Change E-mails Review investigation, which concluded “that it is not uncommon for strongly 

opposed and robustly expressed positions to be taken up in heavily contested areas of science. 

We take the view that such behaviour does not in general threaten the integrity of peer review or 

publication.” The final report of the investigation also stated that the panel has “not found any 

direct evidence to support the allegation that members of CRU [in this case Phil Jones] misused 

their position on IPCC to seek to prevent the publication of opposing ideas”(Russell, 2010). On 

this issue, Brian Hoskins, one of three review editors for Chapter 3, provided statements to the 

Independent Climate Change E-mails Review that were summarized in the panel’s report as 

stating (Russell, 2010): 

Hoskins confirmed that Las [lead authors], working individually and as small groups, 

were responsible for the collation and primary assessment of material relevant to the 

topics for which they were responsible. The CLAs [convening lead authors] led the 

plenary meetings of the writing team prior to production of each of the drafts, led the 

process of overall collation of the Chapter material and the production of the initial drafts 

of the First and Second Draft Reports and the Final Draft Report of the Chapter. These 

drafts were discussed and agreed during plenary meetings of the whole writing team. 

58 
There were a very large number of comments from reviewers, of which a majority were 

from a relatively small group. The Review Editors made sure that they were all given 

proper consideration, and that they were either responded to by a change in the text or by 

an adequate reason for omission that was recorded in the author responses to expert and 

governmental review comments. Hoskins, as a Review Editor, took part in the Chapter 3 

plenary discussions and ensured that conflicting views were addressed. 

Led by the two CLAs, Jones and Trenberth, the writing team for Chapter 3 was assiduous 

in dealing with comments. Hoskins was very impressed by Jones’ attention to detail, and 

the rigor of the Chapter 3 process. 

The levels of confidence and uncertainty reflected in the drafts were based on the 

consensus of a group of CLAs and LAs who were chosen for their expertise and 

experience in relevant fields. Irrespective of whether a paper is published in a peer 

reviewed journal, it is the responsibility of the whole team to assess whether a 

paper‘s conclusions are robust and to justify whether its arguments should carry weight in 

the assessment. These decisions for each draft were taken in plenary sessions of the 

whole team. Hoskins said that it is inconceivable that a paper making significant claims 

relevant to the work of IPCC and the Chapter 3 team would not be considered by the 

team as a whole. The basis for rejecting one of the papers that is a focus of the allegation 

is included in IPCC records. Decisions about the inclusion of the MM2004 [McKitrick 

and Michaels] paper would have been taken by the whole team. Jones’ voice would have 

been one amongst many. 

The petitioners do not present scientific evidence or argument showing that the IPCC assessment 

is inaccurate or that it does not appropriately reflect the degree of scientific consensus on the 

issues discussed. The petitioner’s broad conclusion that this is the case is unsupported by 

evidence or arguments on the science and assessment literature itself. Finally, we note that the 

science regarding this issue was raised in the comment period for the Endangerment Finding and 

responded to in Response 2-29 of the RTC document. Response 2-29 states: 

"In the case of de Laat and Maurellis (2006) and an earlier paper by McKitrick and 

Michaels (2004), IPCC (Trenberth et al., 2007) assessed these papers and noted that the 

locations of greatest socioeconomic development coincided with those most warmed by 

atmospheric circulation changes, which are not limited to urban areas but rather have 

large-scale coherence. When this is taken into account, IPCC concludes that the 

correlation of warming with industrial and socioeconomic development ceases to be 

statistically significant." 

59 
Comment (2-28):

The Southeastern Legal Foundation argues: 

The so-called “science” of global warming has been conducted in an ideologically 

charged environment, such that any possibility of giving due regard to dissenting views 

was foreclosed at the outset. Thus, the conclusions of organizing bodies, especially 

IPCC, cannot be said to reflect scientific “consensus” in any meaningful sense of that 

word. Instead, they reflect a political movement that has commandeered science to the 

service of its agenda. This is “post-normal science”: the long-dreaded arrival of 

deconstructionism to the natural sciences, according to which scientific quality is 

determined not by its fidelity to truth, but by its fidelity to the political agenda. A leading 

climate scientist and contributor to the IPCC, Mike Hulme, has called the IPCC “a classic 

example” of “post normal science.” 

The petitioner further asserts: 

Post-normal science was defined by Eva Kunseler, in her paper “Towards a new 

paradigm of Science” as follows: A new concept of science was introduced by Funtowicz 

and Ravetz during the 1990s...The concept of post-normal science goes beyond the 

traditional assumptions that science is both certain and value-free...The exercise of 

scholarly activities is defined by the dominance of goal orientation where scientific goals 

are controlled by political or societal actors...Scientists’ integrity lies not in 

disinterestedness but in their behaviour as stakeholders.”(Kunseler, 2007) 

Response (2-28):

We first note that this allegation that the IPCC’s work does not represent objective scientific 

assessment but is motivated by a political agenda is not new. The petitioner is rehashing an 

argument previously submitted during public comment on the proposed endangerment finding. 

We responded to numerous comments received regarding the scientific integrity and objectivity 

of the IPCC’s processes in developing its assessment reports in Volume 1, Section 1, of the RTC 

document. 

We note that the evidence submitted by the petitioner—consisting of a newspaper op-ed by Mike 

Hulme in The Guardian (Hulme, 2007) and the definition of “post-normal science” from a nonpeer-reviewed essay by Eva Kunseler (Kunseler, 2007)—are not new; they were both developed 

in 2007. Therefore, it was not impracticable to raise the objection during the public comment 

period and the reasons for the objection did not arise between June 24, 2009, and February 16, 

2010. The petitioner could have raised this comment during the comment period on the 

proposed Endangerment Finding. The petitioner has not shown why it would have been 

impractical to do so. 

In addition, the evidence does not support the petitioner’s allegation that the science behind 

climate change has been developed in a biased and “ideologically charged environment.” The 

petitioner mischaracterizes Hulme’s discussion of post-normal science and defines what he 

meant by “post-normal science” with the use of an unrelated paper by Eva Kunseler that has 

60 
nothing to do with climate change. This is an excerpt of the relevant part of Hulme’s op-ed in 

The Guardian newspaper: 

That science is an unfolding process of discovery is fairly self-evident. The more we 

seem to know, the more questions we seem to need answering. Some avenues of 

scientific inquiry may close off, but many new ones open up. We know a lot more about 

climate change now than 17 years ago when the first IPCC scientific assessment was 

published. And no doubt in another 17 years our knowledge of how the climate system 

works and the impact that humans have made on it will be significantly different to today. 

Yet it is important that on big questions such as climate change scientists make an 

assessment of what they know at key moments when policy or other collective decisions 

need to be made. Today is such a time. But our portrayal of the risks of climate change 

will always be provisional, subject to change as our understanding advances. Having 

challenges to this unfolding process of discovery is essential for science to thrive, as long 

as those challenges play by the methodological rule book that science has painstakingly 

written over many generations of experience. 

The other important characteristic of scientific knowledge - its openness to change as it 

rubs up against society - is rather harder to handle. Philosophers and practitioners of 

science have identified this particular mode of scientific activity as one that occurs where 

the stakes are high, uncertainties large and decisions urgent, and where values are 

embedded in the way science is done and spoken. It has been labelled “post-normal” 

science. Climate change seems to fall in this category. Disputes in post-normal science 

focus as often on the process of science - who gets funded, who evaluates quality, who 

has the ear of policy - as on the facts of science. 

Hulme’s discussion of post-normal science presents his opinion about how societal values and 

policy decisions intersect with the practice of science. His statement does not say or imply that 

post-normal science means that “a political movement [has] commandeered science to the 

service of its agenda,” nor does he state that climate change is a “classic example of post-normal 

science.” In contrast, Hulme stresses that science is a “process of discovery” that thrives on 

challenges that “play by the methodological rule book that science has painstakingly written over 

many generations of experience.” This is clearly not a statement about science being controlled 

by politics, nor a statement that politics have prevented climate change scientists from giving 

“due regard to dissenting views,” as the petitioner asserts. 

Even if Hulme did claim an overly “ideologically charged environment,” this would only 

represent the opinion of one person among numerous scientific fields comprising an immense 

number of scientists, institutions, assessment bodies, and governmental organizations. This 

evidence, presented as a conclusion with no supporting evidence and with no scientific 

explanation of the errors that resulted, would not come close to undermining the credibility and 

quality of the findings of the assessment literature. As described in this volume, and Volume 1 

of the RTC document for the Endangerment Finding, the assessment literature upon which EPA 

based the Endangerment Finding has robust processes and procedures to ensure that the best 

available scientific information is reviewed and assessed, with checks and balances included to 

61 
produce high-quality, unbiased reports. We respond to specific objections raised by petitioners 

regarding the implementation of the IPCC procedures throughout Section 2.2 of this volume. 

We also note that we considered and responded to multiple perspectives and views of climate 

science in the RTC document for the Endangerment Finding, and considered and responded 

again to the various perspectives of the petitioners here in the RTP document and in the Denial. 

As discussed extensively in our responses, the IPCC and the USGCRP also considered 

alternative views in their assessment processes. See Volume 1 of the RTC document and Section 

2.2.2 (Background) of this Volume of the RTP document for a discussion of these report 

development processes. 

We have reviewed the petitioner’s arguments and materials and do not find that they support the 

allegations that the IPCC was co-opted by politics and biased against dissenting views. The 

balance of the scientific literature represented in the assessment reports on climate change, of 

which the IPCC is one, clearly supports the Administrator’s findings. 

Comment (2-29): 

The Ohio Coal Association and the Coalition for Responsible Regulation argue that the CRU emails “demonstrate that climate scientists felt pressured to present a unified front - and an 

agreed-upon narrative of global warming - even when there was not one.” Both petitioners 

reference an e-mail from Keith Briffa to Michael Mann which states: “I tried hard to balance the 

needs of the science and the IPCC, which were not always the same.” Also, as evidence to 

support their argument, the Coalition for Responsible Regulation provides a letter to the IPCC 

from Christopher Landsea, a former IPCC author, in which he states that he could not “in good 

faith continue to contribute to a process that I view as both being motivated by preconceived 

agendas and being scientifically unsound” (Landsea, 2005). 

Response (2-29): 

Seeing the entire content of the e-mails cited by the petitioner is important to place the first issue 

raised by petitioners in context: 

E-mail from Mann to Briffa on Sunday, April 29, 2007

Keith, just a quick note to let you know I’ve had a chance to read over the key bits on last 

millennium in the final version of the chapter, and I think you did a great job. obviously, 

this was one of the most (if not the most) contentious areas in the entire report, and you 

found a way to (in my view) convey the the[sic] science accurately, but in a way that I 

believe I will be immune to criticisms of bias or neglect--you dealt w/ all of the 

controversies, but in a very even-handed and fair way. bravo! I hope you have an 

opportunity to relax a bit now. Looking forward to buying you a beer next time we have 

an opportunity :) mike22

E-mail from Briffa to Mann on Sunday, April 29, 2007

Mike your words are a real boost to me at the moment. I found myself questioning the 

whole process and being often frustrated at the formulaic way things had to be done - 

 

22 E-mail file 1177890796.txt, (April 29, 2007) page 1310, line 44 of PDF version entitled: CRU Emails 1996-

2009.pdf 

62 
often wasting time and going down dead ends. I really thank you for taking the time to 

say these kind words. I tried hard to balance the needs of the science and the IPCC, 

which were not always the same. I worried that you might think I gave the impression of 

not supporting you well enough while trying to report on the issues and uncertainties. 

Much had to be removed and I was particularly unhappy that I could not get the statement 

into the SPM [Statement for Policymakers] regarding the AR4 reinforcement of the 

results and conclusions of the TAR [Third Assessment Report]. I tried my best but we 

were basically railroaded by Susan. I am happy to pass the mantle on to someone else 

next time. I feel I have basically produced nothing original or substantive of my own 

since this whole process started. I am at this moment, having to work on the ENV 

submission to the forthcoming UK Research Assessment exercise, again instead of 

actually doing some useful research! Anyway thanks again Mike.... really appreciated 

when it comes from you 

very best wishes 

Keith23

These two e-mails were written after the release of the Working Group I report of AR4 (IPCC, 

2007e). Michael Mann writes an e-mail showing his approval of the final version of Chapter 6 

(“Paleoclimate”) of Working Group I report (Jansen et al., 2007) and to congratulate Briffa on 

the accomplishment. Keith Briffa responds to show his appreciation for Mann’s e-mail; he 

explains some of the challenges and difficulties he encountered while finalizing the chapter and 

getting it through the ultimate stages of review. As stated in Section 2.2.2 (Background) and 

Response 2-16 above, Chapter 6 had two convening authors and 14 lead authors from 12 

countries, 33 contributing authors from nine countries, and two review editors who oversaw the 

handling of more than 2,900 comments from the rounds of expert and governmental review. It is 

perfectly understandable and reasonable that Briffa, who was one of the 14 lead authors, would 

have been frustrated by some of the challenges in examining all of the available scientific 

literature on topics related to paleoclimate (whether or not it agrees with the dominant paradigms 

and whether or not it has yet stood the test of time compared to other studies that have 

considered the topic), putting that literature in context through a process of assessment, distilling 

the information into key messages that capture the state of knowledge at the time of the 

assessment, addressing all of the expert and government reviews, and developing key points for 

the summary for policymakers. Briffa’s e-mail does not support the petitioner’s allegation that 

he “felt pressured to present a unified front - and an agreed-upon narrative of global warming - 

even when there was not one.” The petitioner is taking Briffa’s statement that he “tried hard to 

balance the needs of the science and the IPCC, which were not always the same” completely out 

of context and making unsupported allegations. Although he describes some frustrations with 

the challenges of the IPCC’s rigorous and robust report development procedures, Briffa’s e-mail 

does not indicate that he was not satisfied with the final version, that he did not agree with the 

conclusions, nor that he felt pressured in any way to “present a unified front.” 

 

The e-mails in question also reveal that the process of scientific assessment is personally and 

professionally challenging because scientists who volunteer their time are taken away from their 

 

23 E-mail file 1177890796.txt, (April 29, 2007) page 1310, line 24 of PDF version entitled: CRU Emails 1996-

2009.pdf 

63 
own research and must sideline their own personal views of what should and should not be 

included in the reports. In fact, Michael Mann compliments Keith Briffa’s objectivity and evenhandedness in handling the challenges. Briffa also clearly expresses frustration with the time 

spent away from doing new science, which is not the primary job of an IPCC chapter author or 

of the IPCC in general. The primary role of the IPCC is to assess existing science already 

published in the literature, i.e., in Briffa’s words, “the needs of the science and the IPCC” are not 

always the same. In context, it is clear that the needs of the IPCC in this case are the “formulaic 

way things had to be done” and the need to do assessments of existing literature rather than 

producing “original and substantive” work or “useful research.” It appears original research 

would be what Briffa is referring to as the needs of the science. When the e-mails are read in 

their full context, it is clear that the authors of these e-mails sought to convey the science 

accurately and address all the controversies in a fair and even-handed way. Again, petitioners 

appear to have selectively picked excerpts from emails. 

We note that the Landsea letter provided by the Coalition for Responsible Regulation is not new. 

As stated in the link of the letter provided by the petitioner (Taylor, 2005), Landsea wrote this 

letter in January 2005. Therefore, it was not impracticable to raise the objection during the 

public comment period and the reasons for the objection did not arise between June 24, 2009, 

and February 16, 2010. The petitioner could have raised this comment during the comment 

period on the proposed Endangerment Finding. The Coalition for Responsible Regulation has 

not shown why it would have been impracticable to do so, especially given the fact that the 

public has been aware that EPA might rely on the IPCC assessments since the July 2008 

Advance Notice of Proposed Rulemaking. 

Despite this, we will respond briefly to the petitioner’s allegations. Christopher Landsea served 

as a contributing author for the IPCC Second and Third Assessment Reports (IPCC 1995, IPCC 

2001), but chose not to participate in AR4. In the initial planning stages of the AR4, Landsea 

wrote this letter to the IPCC expressing his disapproval with IPCC procedures. Specifically, 

Landsea disapproved of the fact that Kevin Trenberth, an IPCC lead author for the TAR, 

purportedly used his position to “promulgate to the media and general public his own opinion 

that the busy 2004 hurricane season was caused by global warming, which is in direct opposition 

to research written in the field and is counter to conclusions in the TAR [Third Assessment 

Report].” Landsea went on to state that “As the IPCC leadership has seen no wrong in Dr. 

Trenberth’s actions and have retained him as a Lead Author for the AR4, I have decided to no 

longer participate in the IPCC AR4.” This letter shows that Landsea disagreed with Trenberth 

regarding a particular aspect of the attribution of hurricanes to climate change and that Landsea 

did not approve of Trenberth representing the IPCC when discussing his views about the issue. 

This impact of climate change on hurricane activity is a very dynamic issue. There are still 

significant uncertainties in the underlying climate science, so it not surprising that two scientists 

would disagree regarding the attribution of the 2004 hurricane season to climate change effects. 

However, the contents of the letter do not “demonstrate that climate scientists felt pressured to 

present a unified front - and an agreed-upon narrative of global warming - even when there was 

not one,” as alleged by the petitioner. Landsea was not taking issue with the content of the IPCC 

reports, but with how Trenberth discussed certain issues during the period between the Third and 

Fourth Assessment Reports. The fact that Landsea disapproved of how Trenberth represented 

64 
the IPCC in discussing a specific scientific issue at a press conference preceding development of 

the AR4 provides absolutely no support for petitioners’ claim that the conclusions reached in 

AR4 are incorrect or biased, or that they were developed in a way that pressured scientists into 

presenting “a united front.” The petitioners did not provide any evidence to support that 

conclusion. 

We also note that the discussion in AR4 of uncertainties associated with the impact of climate 

change on hurricane activity reflected the ongoing debate and alternative views on the issues. 

EPA also clearly described the uncertainties related to hurricane activity and climate change in 

the TSD and again in Volumes 2 and 4 of the RTC document for the Endangerment Finding. 

Finally, our response to allegations involving the IPCC’s characterization of climate change and 

disaster losses can be found in Subsection 2.1.4 of this volume of the RTP document. 

2.2.4 Responses to Allegations Based on Information That Is Not New 

The petitioners submitted four objections concerning: 1) the collaborations among IPCC authors, 

2) the general IPCC peer review process, 3) the alleged manipulation of dates and deadlines for 

accepting literature, and 4) the IPCC’s use of gray literature. EPA has reviewed the petitioners’ 

submissions and finds that it was not impracticable to raise the objection during the public 

comment period and that the reasons for the objection did not arise between June 24, 2009, and 

February 16, 2010. The IPCC AR4 has been public since early 2007, and petitioners could have 

raised these comments during the comment period on the proposed Endangerment Finding. 

Although, in most cases, the petitioners provide excerpts from the CRU e-mails in support of 

their assertions, EPA’s review has determined that this evidence does not support their 

allegations, and that the vast majority of the information submitted by petitioners on these topics 

was available well before the comment period for the Endangerment Finding. Petitioners have 

not shown why it would have been impracticable for them to raise these issues then, especially 

given the fact that the public has been aware that EPA relied, in part, on the IPCC assessments 

since the July 2008 ANPR. Indeed, some of these same points were already raised, and 

responded to, in the RTC. 

Despite the fact that these objections fail to meet the criteria for a petition for reconsideration, we 

briefly explain why, contrary to petitioners’ allegation, they fail to call into question the overall 

integrity or validity of the IPCC AR4. As noted above, very similar comments questioning the 

appropriateness of IPCC author and reviewer roles were submitted and responded to during the 

development of the Findings (see Volume 1 of the RTC document). 

2.2.4.1 Allegations of Inappropriate Collaborations Among IPCC Authors 

Comment (2-30): 

The State of Texas, Peabody Energy, and the Coalition for Responsible Regulation contend that 

the CRU e-mails show that IPCC authors and reviewers are close associates who frequently 

collaborate on projects and studies, and claim that such collaborations create conflicts of interest 

(for example, when one person authors an IPCC chapter and another serves as an official 

reviewer). Peabody Energy argues that the Wegman Report, Social Network Analysis of 

Authorship in Temperature Reconstruction, confirms that IPCC scientists are closely networked 

65 
with each other and dominate their field. The petitioner references testimony given by Edward J. 

Wegman (George Mason University) to Congress (Wegman, 2006) in arguing that “the 

paleoclimate field is dominated by interlinked scientists who no longer produce research that has 

the desired degree of independence.” 

Based on this report, Peabody Energy provides a detailed example of the small paleoclimate 

research community and how these scientists frequently co-author papers together, review each 

other’s papers, and collaborate in other ways that generate conflicts of interest. Specifically, the 

petitioner, in referring to Chapter 9 (“Understanding and Attributing Climate Change”) of 

Working Group I’s contribution to the AR4 (Hegerl et al., 2007), provides a series of statistics 

that were also provided to EPA during the public comment period (these statistics are provided 

below) and argues that EPA did not respond to these specific issues in the RTC document: 

 Forty of the 53 authors of this chapter co-authored papers with each other. 

 More than half of the contributing authors co-authored papers with lead authors or 

coordinating lead authors. 

 The review editor of the chapter contributed to 13 papers cited in the chapter and had coauthored these papers with 10 other authors of Chapter 9. 

 Of the published papers in Chapter 9: 

o 94 were authored by two or more of that chapter’s authors. 

o One cited paper had six chapter authors. 

o Five cited papers had five chapter authors. 

o 26 papers had three chapter authors, including six papers written entirely by 

chapter authors. 

o 50 of the cited papers listed two chapter authors each, and 10 of these papers were 

written entirely by chapter authors. 

Response (2-30):

Neither the facts nor the evidence provided support the petitioners’ claim that the collaborations 

among climate researchers led to conflicts of interest and bias, or that these collaborations 

interfered with their ability to be objective and impartial. Some climate science fields (e.g., 

paleoclimatology) are highly specialized and are the focus of only a limited number of 

researchers. In such fields, scientists who have at one point in the past collaborated on work can 

be called on to review each other’s work. This practice is common in a variety of scientific areas 

with a relatively limited number of researchers, not just these specific climate science fields. It is 

actually the most robust practice of ensuring scientific credibility, because the reviewing 

scientists are the true experts who know the material and are most capable of fulfilling the review 

role. Petitioners’ conclusions of impropriety or bias are not supported by the mere fact that 

authors know each other and have collaborated. 

We respond to Peabody Energy’s statistics regarding Chapter 9 in Subsection 2.2.3.2 of this 

volume of the RTP document. Given the limited number of researchers in this particular area, 

the statistics regarding author and reviewer roles in Chapter 9 of Working Group I’s contribution 

66 
to the AR4 (Hegerl et al., 2007) are not surprising and do not indicate, as alleged by the 

petitioner, that there were “built-in conflicts of interest that had the potential for undermining the 

reliability of the reports.” Rather, these statistics show that the most qualified and experienced 

authors and reviewers were involved in developing that particular chapter. EPA carefully 

reviewed and responded to these statistics regarding collaborations among IPCC authors in 

Volume 1 of the RTC document. 

Furthermore, all scientific papers have to abide by strict ethical, conflict of interest, and scientific 

integrity/quality rules. The evidence provided by the petitioners does not show that these rules 

have been broken, that the peer-review system has been compromised, or that the assessment 

literature did not consider a range of perspectives in summarizing the state of the science. 

Essentially, the petitioners’ argument can be boiled down to the view that if scientists work 

together and know each other, something improper is probably happening. This is an 

unwarranted and unjustified view of professional relationships, based on pure speculation. 

Finally, we note that Peabody Energy does not provide any evidence to support its allegation that 

the past collaborations of these authors and reviewers actually led to “less than fully independent 

and rigorous” assessments of the science. The petitioner provided limited and unsubstantiated 

critiques of the science presented in Chapter 9, which we address in Volume 1 of this RTP 

document. Peabody Energy also provides no scientific argument or analysis indicating that the 

research produced by theses scientists or the IPCC chapter at issue was in any way biased or less 

than scientifically rigorous. 

2.2.4.2 Allegations Regarding Insufficient Peer Review Processes for the IPCC 

Comment (2-31):

Peabody Energy claims that the IPCC’s peer review process is less robust and credible than the 

processes employed by scientific journals because IPCC lead and contributing authors are the 

ones who decide whether to accept or reject critical reviews. The petitioner argues that the 

IPCC’s process is flawed because there is no neutral scientist, who was not involved in the 

writing, to ensure that the reviews are judged objectively. 

Response (2-31): 

First, we note that the petitioner provides no new information to substantiate their allegation, and 

that Peabody Energy’s argument regarding the rigor of the IPCC’s peer review does not 

accurately describe the actual review process used by the IPCC. As described above in 

Subsection 2.2.2 (Background) of this volume, lead and contributing authors are indeed tasked 

with initially responding to comments; however, independent and objective review editors (i.e., 

editors not involved in the writing of the chapter) are assigned to each chapter to ensure that each 

comment is addressed properly and accurately. Furthermore, the contributing authors are not 

allowed to simply reject critical reviews without documenting their rationale. The IPCC 

carefully documented all comments received on the first and second order drafts of each chapter 

of each working group. These comments and responses are, and have always been, publically 

available (IPCC, 2006a for Working Group I and IPCC, 2005 for Working Group II). 

67 
In addition, it would be illogical and inappropriate for the IPCC, as suggested by the petitioner, 

to allow only unrelated parties to respond to comments on chapters that they did not write. What 

the petitioner seems to believe would be appropriate—allowing unrelated people to respond to 

comments on the draft documents, as opposed to having the authors respond and revise their 

drafts—makes absolutely no sense and is not common in any scientific discipline because the 

unrelated parties would not possess the experience and context necessary to properly understand 

and respond to the comments. We therefore disagree with the petitioner’s argument that the 

IPCC’s peer review procedures are less rigorous than the processes employed by scientific 

journals. Petitioners provide no evidence that the IPCC authors inappropriately influenced the 

response to comments process or that review editors failed to perform their role in ensuring that 

all comments were properly addressed. The mere allegations and conclusory claims made by the 

petitioner are insufficient to support the broad conclusion they draw. Finally, we note that the 

petitioner did not provide examples of other peer review processes that they deemed to be more 

robust and credible than those procedures employed by the IPCC. 

2.2.4.3 Allegations That IPCC Authors Manipulated Deadlines for New Literature 

Comment (2-32): 

Peabody Energy argues that the IPCC manipulated dates and deadlines for receipt of new 

literature to provide additional evidence in substantiating its conclusions regarding 20th-century 

warming. Specifically, the petitioner provides an example of two papers (both by Caspar 

Ammann and Eugene Wahl) on long-term temperature reconstructions, one of which was 

allegedly allowed to be referenced by IPCC authors in the AR4 only because, the petitioners 

claim, the IPCC manipulated the deadline for receipt of literature. 

Response (2-32): 

The evidence provided by Peabody Energy does not demonstrate that the IPCC, specifically the 

lead author of Chapter 6 of Working Group I’s contribution to the AR4 (Jansen et al., 2007), 

manipulated the deadline for receipt of new literature for the purpose of including the two papers 

by Ammann and Wahl (Ammann and Wahl, 2007; Wahl and Ammann, 2007). We note that the 

IPCC AR4 has been public since early 2007, and petitioners could have raised these objections 

during the comment period on the proposed Endangerment Finding. Petitioners have not shown 

why it would have been impractical for them to do so. The only part of their argument that is 

“new” (i.e., has arisen since the close of the comment period on June 23, 2009) is an e-mail 

between Wahl and Ammann, which is a very minor part of their overall interaction. The e-mail 

only shows that Wahl and Ammann were making final proofing edits in September 2007. The email stated: 

Hi Phil: 

There were inevitably a few things that needed to be changed in the final version of the 

WA paper, such as the reference to the GRL paper that was not published (replaced by 

the AW paper here), two or three additional pointers to the AW paper, changed 

references of a Mann/Rutherford/Wahl/Ammann paper from 2005 to 2007, and a some 

other very minor grammatical/structural things. I tried to keep all of this to the barest 

minimum possible, while still providing a good reference structure. I imagine that MM 

[Ross McKitrick and Pat Michaels] will make the biggest issue about the very existence 

68 
of the AW paper, and then the referencing of it in WA; but that was simply something we 

could not do without, and indeed AW does a good job of contextualizing the whole 

matter. Steve Schneider seemed well satisfied with the entire matter, including its 

intellectual defensibility (sp?) and I think his confidence is warranted. That said, any 

other thoughts/musings you have are quite welcome. 

Peace, Gene24 

As stated by the petitioner, the deadline for receipt of new literature was changed during the 

development of the Working Group I report. The deadline was originally December 2005 and 

was changed to July 24, 2006. When the coordinating lead authors for Working Group I 

extended the deadline for receipt of new literature, they provided the following justification 

(IPCC, 2006b): 

To ensure clarity and transparency in determining how such material might be included 

in the final Working Group I report, the following guidelines will be used by Lead 

Authors in considering such suggestions. In preparing the final draft of the IPCC 

Working Group I report, Lead Authors may include scientific papers published in 2006 

where, in their judgment, doing so would advance the goal of achieving a balance of 

scientific views in addressing reviewer comments. 

The authors of Chapter 6 followed this guidance and included the Wahl and Ammann (2007) 

study. We note that the Wahl and Ammann paper was accepted into Climatic Change on March 

1, 2006, which means that at that point, the paper had passed peer review and the editor had 

agreed with the reviewers regarding its merit for publication. Thus, although the citation for the 

paper is in 2007, the acceptance date met the IPCC’s revised deadline of July 24, 2006, for 

receipt of new literature that was established by AR4 lead authors. It appears that the same 

authors’ other paper, Ammann and Wahl (2007), was not accepted for publication in time to 

meet the extended deadline for receipt of new literature, and we note that it is therefore not 

referenced in Chapter 6 of the AR4. 

The petitioner alleges impropriety because the IPCC referenced Wahl and Ammann (2007), even 

though some of the underlying statistical analysis for that study, which was eventually published 

in Amman and Wahl (2007), had not been accepted for publication by the extended deadline. 

There are two flaws with petitioner’s arguments. First, in the event that any of the expert 

reviewers for Chapter 6 expressed concern regarding the Wahl and Ammann (2007) paper, they 

would have had the opportunity to request any supplemental information necessary for reviewing 

the credibility of the Wahl and Ammann results. Second, the Ammann and Wahl paper went 

through peer review and was eventually published in Climatic Change in 2007, in the same issue 

as Wahl and Ammann (2007). The petitioners do not claim or demonstrate that the methods or 

results described in the Ammann and Wahl paper were incorrect or flawed. They simply allege 

that a decision to change deadlines slightly is “manipulation,” even if no scientific flaw or 

challenge is raised against the literature affected by the date change. 

 

24 E-mail file 1189722851.txt, (September 12, 2007), page 1357, line 6 of PDF version entitled: CRU Emails 1996-

2009.pdf 

69 
Moreover, contrary to the petitioner’s argument, the evidence provided by the petitioner does not 

indicate that the deadline was inappropriately extended to accommodate the inclusion of these 

papers in AR4. On this issue, the Independent Climate Change E-mails Review found that: 

Taking into account the evidence of the Review Editor [for Chapter 6, i.e. John Mitchell], 

IPCC papers [documentation of IPCC responses to comments], the statement from the 

CLA [Jonathan Overpeck], and the importance of the issues raised by M&M2003 

[McIntyre and McKitrick], we consider it to be reasonable that work that might throw 

further light on these issues and to ensure that assessments were as up to date as possible 

should be included. We do not consider therefore that these were exceptional 

unwarranted efforts to defend a particular position, but reasonable attempts to use up to 

date information that might resolve an issue. They appear to be consistent with IPCC 

principles and to reflect a concern for objectivity (Russell, 2010). 

There was a general decision to allow extension of the deadline for the entire Working Group, 

and the chapter authors applied this guidance and extended the deadline for scientific studies 

relevant to that chapter. The fact that it was extended does not show it was extended because of 

these specific papers. In addition, petitioners have not shown that the extension altered the 

results of the report or the appropriateness of EPA’s relying on it. First, inclusion of the peerreviewed study represents one very small part in the deliberate preparation and review of a multivolume assessment containing several thousands of pages of findings and conclusions. Second, 

Chapter 6 relied upon a number of long-term temperature reconstructions for its conclusions, 

including the findings of NRC’s 2006 report (NRC, 2006) on surface temperature 

reconstructions. The NRC findings were fully consistent with the conclusions of the Ammann 

and Wahl papers. The papers in question provided additional, but not the only, evidence 

concerning the validity of using long-term proxy temperature reconstructions to compare 

historical and current climates. Indeed, and perhaps most importantly, the petitioner has 

provided no evidence showing that the conclusions of the Ammann and Wahl paper were 

mistaken or incorrect, or that the conclusions by themselves changed the findings of Chapter 6. 

Third, we note the statements that John Mitchell, one of two Chapter 6 review editors for 

Chapter 6, provided to the Independent Climate Change E-mails Review regarding how in-press 

material was handled and how decisions about the text of successive drafts were made. He 

commented as follows: 

I was not aware of the debate about whether the Wahl and Ammann paper had or had not 

met the deadline for the 2nd order draft for chapter 6, until after the event. The 

concentration on specific deadlines however misses the larger point. It must be 

recognized that if only published sources were used, the report would be two years old by 

the time of publication. In a fast-moving area such as climate change research, 

assessments could be significantly behind the times if important, but as yet unpublished, 

new results could not be used. The assessments for policymakers could also therefore be 

behind the times... 

In earlier assessments, there had been a relatively liberal regime in using unpublished 

material provided that there was a sound basis for regarding it as rigorous or reliable, 

although priority was always given to finding published sources. In AR4 however, the 

70 
regime was tightened significantly, so that such material was only to be used under 

exceptional circumstances, but the use of unpublished material was not prohibited. 

Hockey-stick issues were regarded at the time as sufficiently important to justify using 

new data. The dilemma between using only published material and being out of date, or 

using more recent unpublished material was increased in AR4 as the latest publication 

date was about 12 months earlier than in the process than in the previous assessment 

(Russell, 2010). 

2.2.4.4 Allegations Regarding the IPCC’s Use of Gray Literature 

Comment (2-33):

The Coalition for Responsible Regulation, Peabody Energy, the Southeastern Legal Foundation, 

and the State of Texas argue that the IPCC’s use of non-peer-reviewed literature (e.g., reports 

they claim are developed by environmental advocacy groups) in the AR4 calls into question the 

quality and objectivity of these pieces of literature and contradicts EPA’s assertion that the IPCC 

is based on peer-reviewed science. The petitioners provide examples of gray literature sources 

that were used by the IPCC in AR4. 

Response (2-33):

First, we note that the petitioners provided no new information in support of their allegations. As 

stated above, the petitioners are simply rehashing a comment that was submitted and responded 

to in the development of the Findings. Therefore, we find that their allegations were not 

impracticable to raise the objection during the public comment period and the reasons for the 

objection did not arise between June 24, 2009, and February 16, 2010. The IPCC AR4 has been 

public since early 2007, and petitioners could have raised these comments during the comment 

period on the proposed Endangerment Finding. Petitioners have not shown why it would have 

been impracticable for them to raise these issues then, especially given the fact that the public 

has been aware that EPA relied, in part, on the IPCC assessments since the July 2008 ANPR. 

The IPCC relied on and referenced a very limited number of non-peer-reviewed sources in 

developing AR4. The IPCC’s report development procedures recognized and allowed for the 

limited use of non-peer-reviewed literature where this was necessary and appropriate. Indeed, 

neither the IPCC nor EPA ever stated that the assessment reports relied exclusively on peerreviewed material. For EPA’s responses showing how the limited use of gray literature 

documents did not undermine the IPCC’s scientific findings and the technical support for 

endangerment, please see Section 2.1 of this volume, including Responses 2-8, 2-9, and 2-10. 

Looking across the thousands of scientific studies reviewed, assessed, and referenced by the 

IPCC in the AR4, it is clear that the number of non-peer-reviewed documents was dwarfed by 

the number of peer-reviewed references (estimated by the IPCC to be approximately 18,000). 

The IPCC, as clearly described in Volume 1 of the RTC document, has specific procedures to 

ensure that any non-peer-reviewed materials are sufficiently robust and credible in the context in 

which they were cited. While there are a very few instances in which erroneous conclusions 

were developed from the gray literature sources (see Section 2.1 of this RTP document for more 

detail on our responses to these issues), the overall process is exceedingly robust. Furthermore, 

71 
the few errors in this regard are trivial when viewed against the backdrop of the IPCC’s multivolume assessment containing several thousand pages of findings and conclusions. The few 

errors do not affect the climate change science findings or have any material or meaningful 

implication for the determination of endangerment to public health and welfare in the United 

States. The examples of gray literature provided by the petitioners were not cited by EPA in 

describing the key IPCC conclusions that EPA relied on in developing the TSD (U.S. EPA, 

2009). The examples provided by the petitioners are cited in chapters of the Working Group II 

and III AR4 reports when describing climate change impacts in other world regions, which was 

not a focus of the TSD. 

Comment (2-34): 

Peabody Energy claims that the IPCC Working Group II “frequently used a citation method that 

did not candidly reveal an underlying affiliation with an environmental advocacy group.” For 

example, the petitioner claims that in many instances the IPCC report “referred only to the name 

of the author when the work was actually sponsored by an interest group” such as the World 

Wildlife Fund. Peabody concludes that “It is unclear whether these sponsored works provide 

independent, objective, and peer-reviewed science that should be the basis for AR4, or whether 

they advance the environmental agenda of their sponsor. It is also unclear whether these sources 

were independently verified by IPCC authors and contributors.” 

Response (2-34):

First, we note that the IPCC’s citation method for the AR4 is not new and that this information 

has been known since the assessment report was released in 2007 (IPCC, 2007a). Therefore, the 

petitioner’s arguments were not impracticable to raise during the public comment period and the 

reasons for the objection did not arise between June 24, 2009, and February 16, 2010. The 

petitioner could have raised this comment during the comment period on the proposed 

Endangerment Finding. Peabody Energy has not shown why it would have been impractical to 

do so. Despite this, we respond below to the merits of their argument. 

The petitioner alleges that the IPCC employed a parenthetical citation method in the text of the 

chapters that hid information showing that references were developed by environmental nongovernment organizations. In fact, the IPCC employed a common citation method for the 

thousands of studies that are referenced among the more than 3,000 pages in AR4. This format 

consists of listing the author’s names first for each entry in the references section, and 

mentioning the publisher and/or organization (e.g., World Wildlife Fund) toward the end of the 

reference. Parenthetical citations, for each reference in the text of a chapter, list the author(s)’ 

name(s) and the year of publication. This citation methodology is consistent with many 

established citation guidelines, including those developed by the Modern Language Association, 

the American Psychological Association, and the University of Chicago. 

The evidence provided by the petitioner does not show that the IPCC hid the fact that some of 

the reports it cited were developed by non-government organizations like the World Wildlife 

Fund. The petitioner seems to suggest that the IPCC should have included the names of the nongovernment organizations in the parenthetical citations for these literature sources. However, 

this practice is contrary to the well-established conventions and styles that are commonly used in 

all disciplines of science and literature. Special treatment for these literature sources would be 

72 
inappropriate and unreasonable, and the petitioner’s only justification for such an approach is the 

speculation that this literature might have been created to “advance the environmental agenda of 

their sponsor.” Again, the IPCC included the names of the organizations in the full reference for 

each report in the references section at the end of each chapter. The IPCC did not hide the 

publisher or sponsoring organization’s name. 

For our response to the petitioner’s argument that “It is unclear whether these sponsored works 

provide independent, objective, and peer-reviewed science that should be the basis for AR4, or 

whether they advance the environmental agenda of their sponsor,” please see Section 2.1 of this 

volume, including Responses 2-8, 2-9, and 2-10. 

Finally, the procedures employed by the IPCC in evaluating sources of gray literature are 

described in Section 1 and Appendix A of Volume 1 of the RTC document. The petitioner has 

provided no evidence suggesting that the reports developed by environmental non-government 

organizations were not evaluated by AR4 authors according to the IPCC’s procedures. 

2.2.5 Summary 

The evidence provided by the petitioners does not support their allegations that the IPCC’s peer 

review and report development processes are designed inappropriately, or that they were 

inappropriately implemented in the development of the AR4. Specifically, the evidence 

provided by the petitioners and all of the information in the record for the Endangerment Finding 

shows that, contrary to the claims of the petitioners: 

 It was proper to not list certain scientists as contributing authors as they did not 

contribute significantly to the writing and editorial decisions in developing any AR4 

chapter, including Chapter 6 of Working Group I’s contribution (Jansen et al., 2007), and 

therefore did not compromise their objectivity during the peer-review process. 

 IPCC authors did not cite their own studies more frequently than what was acceptable 

and reasonable. 

 IPCC authors were not directed to focus on policy-prescriptive conclusions, but rather 

implemented IPCC guidelines by presenting policy-relevant and neutral findings. 

 IPCC authors did not alter the content of reports to eliminate suggestions of 

nonconsensus. 

 Collaborations among IPCC authors and reviewers prior to the development of AR4 did 

not compromise objectivity or generate conflicts of interest. 

 The IPCC’s peer-review processes are appropriate and adequate, and were properly 

implemented. 

 IPCC authors did not manipulate deadlines for receipt of new literature. 

73 
 The IPCC’s very limited use of gray literature does not call into question the quality and 

objectivity of the assessment reports. 

Petitioners do not present scientific evidence or argument showing that the Chapters of 

assessment report at issue are inaccurate or that they do not appropriately reflect the range of 

scientific evidence and the degree of scientific consensus on the scientific issues discussed. The 

evidence they present does not support the broad assertion that this is the case. They do not 

present credible scientific evidence or arguments on the science itself to support their claims. 

Therefore, petitioners’ evidence and arguments do not support changing our position, as stated in 

the Endangerment Finding, that the assessment literature, including the IPCC AR4, represents 

the “best reference materials for determining the general state of knowledge on the scientific and 

technical issues before the agency in making an endangerment decision.” 

74 
References 

Adam, D., and S. Goldenberg (2010). How to reform the IPCC. The Guardian. Available at: 

http://www.guardian.co.uk/environment/2010/feb/10/ipcc-reform. Accessed July 23, 

2010. 

Agoumi, A. (2003). Vulnerability of North African countries to climatic changes. International 

Institute for Sustainable Development and the Climate Change Knowledge Network. 

Available at: http://www.cckn.net//pdf/north_africa.pdf. Accessed July 23, 2010. 

Ammann, C., and E. Wahl (2007). The importance of the geophysical context in statistical 

evaluations of climate reconstruction procedures. Climatic Change 85: 71–88. 

Anyamba, A., and C.J. Tucker (2005). Analysis of Sahelian vegetation dynamics using NOAAAVHRR NDVI data from 1981–2003. Journal of Arid Environments 63: 596–614. 

Barnett, T.P., J.C. Adam, and D.P. Lettenmaier (2005). Potential impacts of a warming climate 

on water availability in snow-dominated regions. Nature 438:303–309. 

Bindoff, N.L., et al. (2007). Observations: oceanic climate change and sea level. In: Climate 

change 2007: the physical science basis. Contribution of Working Group I to the Fourth 

Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. 

Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. 

Cambridge University Press, Cambridge, UK, and New York, NY, USA. 

Boko, M., I. Niang, A. Nyong, C. Vogel, A. Githeko, M. Medany, B. Osman-Elasha, R. Tabo, 

and P. Yanda (2007). Africa. In: Climate change 2007: impacts, adaptation and 

vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the 

Intergovernmental Panel on Climate Change [M.L. Parry, O.F. Canziani, J.P. Palutikof, 

P.J. van der Linden and C.E. Hanson (eds.)]. Cambridge University Press, Cambridge, 

UK. pp. 433-467. 

Booker, C., and R. North (2009). Questions over business deals of UN climate change guru Dr 

Rajendra Pachauri. The Daily Telegraph. 

CCSP (2009a). Coastal sensitivity to sea-level rise: a focus on the Mid-Atlantic region. A report 

by the U.S. Climate Change Science Program and the Subcommittee on Global Change 

Research. [J.G. Titus (coordinating lead author), K.E. Anderson, D.R. Cahoon, D.B. 

Gesch, S.K. Gill, B.T. Gutierrez, E.R. Thieler, and S.J. Williams (lead authors)]. U.S. 

Environmental Protection Agency, Washington, DC, USA. 320 pp. 

CCSP (2009b). Announcements of IPCC public comment period. Available at: 

http://www.climatescience.gov/Library/ipcc/default.htm. Accessed July 23, 2010. 

CCSP (2008). Weather and climate extremes in a changing climate. Regions of focus: North 

America, Hawaii, Caribbean, and U.S. Pacific Islands. A report by the U.S. Climate 

75 
Change Science Program and the Subcommittee on Global Change Research [T.R. Karl, 

G.A. Meehl, C.D. Miller, S.J. Hassol, A.M. Waple, and W.L. Murray (eds.)]. Department 

of Commerce, NOAA National Climatic Data Center, Washington, DC, USA. 164 pp. 

CCSP (2004). Guidelines for producing CCSP synthesis and assessment products. Washington, 

DC. http://www.climatescience.gov/Library/sap/sap-guidelines.pdf. Accessed July 23, 

2009. 

Christensen, J.H. et al. (2007) Regional Climate Projections. In: Climate Change 2007: The 

Physical Science Basis. Contribution of Working Group I to the Fourth Assessment 

Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. 

Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. 

Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. 

Coudrain, A., B. Francou, and Z.W. Kundzewicz (2005). Glacier shrinkage in the Andes and 

consequences for water resources. Hydrol. Sci. J. 50: 925–932. 

Cox, P.M., R.A. Betts, M. Collins, P. Harris, C. Huntingford, C.D. Jones (2004). Amazon 

dieback under climate-carbon cycle projections for the 21st century. Theor. Appl. 

Climatol. 78: 137–156. doi:10. 1007/s00704-004-0049-4. 

Cox, P.M., R.A. Betts, C.D. Jones, S. Spall, and I.J. Totterdell (2000). Acceleration of global 

warming due to carbon-cycle feedbacks in a coupled climate model. Nature 408: 184–

187. 

Cruz, R., et al. (2007). Asia. In: Climate change 2007: impacts, adaptation and vulnerability.

Contribution of Working Group II to the Fourth Assessment Report of the 

Intergovernmental Panel on Climate Change [M.L. Parry, O.F. Canziani, J.P. Palutikof, 

P.J. van der Linden, and C.E. Hanson (eds.)]. Cambridge University Press, Cambridge, 

UK, and New York, NY, USA. 

De Laat, A.T.J., and A.N. Maurellis (2006). Evidence for influence of anthropogenic surface 

processes on lower tropospheric and surface temperature trends. International Journal of 

Climatology 26: 897–913. 

Dyurgerov, M., and M.F. Meier (2005). Glaciers and the Changing Earth System: A 2004 

Snapshot. Occasional Paper 58, Institute of Arctic and Alpine Research, University of 

Colorado, Boulder, CO, 118 pp. 

Easterling, W., et al. (2007). Food, fibre and forest products. In: Climate change 2007: impacts, 

adaptation and vulnerability. Contribution of Working Group II to the Fourth Assessment 

Report of the Intergovernmental Panel on Climate Change [M.L. Parry, O.F. Canziani, 

J.P. Palutikof, P.J. van der Linden, and C.E. Hanson (eds.)]. Cambridge University Press, 

Cambridge, UK, and New York, NY, USA. 

76 
Field, C.B., L.D. Mortsch,, M. Brklacich, D.L. Forbes, P. Kovacs, J.A. Patz, S.W. Running, and 

M.J. Scott (2007). North America. In: Climate change 2007: impacts, adaptation and 

vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the 

Intergovernmental Panel on Climate Change [M.L. Parry, O.F. Canziani, J.P. Palutikof, 

P.J. van der Linden, and C.E. Hanson (eds.)]. Cambridge University Press, Cambridge, 

UK. pp. 617-652. 

Harvey, F. (2010). Climate chief cleared over payments. Financial Times. Available at: 

http://www.ft.com/cms/s/0/44a0a92c-3a8e-11df-b6d5-00144feabdc0.html. Accessed July 

23, 2010. 

Hasnain, S.I. (2002). Himalayan glaciers meltdown: impacts on South Asian Rivers. FRIEND 

2002-Regional Hydrology: Bridging the Gap between Research and Practice [H.A.J. van 

Lanen and S. Demuth (eds.)]. IAHS Publications, Wallingford, No. 274, 417-423. 

Available at: http://sciencepolicy.colorado.edu/admin/publication_files/resource-2449-

2006.02.pdf. Accessed July 23, 2010. 

Hegerl, G.C., et al. (2007). Understanding and attributing climate change. In: Climate Change 

2007: the physical science basis. Contribution of Working Group I to the Fourth 

Assessment Report of the Intergovernmental Panel on Climate Change [Solomon, S., D. 

Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor, and H.L. Miller (eds.)]. 

Cambridge University Press, Cambridge, UK, and New York, NY, USA. 

Hulme, M. (2007). The appliance of science. The Guardian. Available at: 

http://www.guardian.co.uk/society/2007/mar/14/scienceofclimatechange.climatechange. 

Accessed July 23, 2010. 

Hulme et al. (2001). African climate change: 1900–2100. Climate Research 17: 145–168. 

Hutchinson, C.F., S.M. Herrmann, T. Maukonen, and J. Weber (2005). Introduction: the 

“greening” of the Sahel. Journal of Arid Environments 63: 535–537. 

Indo-Asian News Service (2010). India to have own panel on climate change: Jairam Ramesh. 

Hindustan Times. Available at: http://www.hindustantimes.com/India-to-have-ownpanel-on-climate-change-Jairam-Ramesh/H1-Article1-505242.aspx. Accessed July 23, 

2010. 

IPCC (2010a). Summary description of the IPCC process. (December 2009). Intergovernmental 

Panel on Climate Change. Available at: http://www.ipccwg1.unibe.ch/statement/WGIsummary22122009.html. Accessed July 23, 2010. 

IPCC (2010b). Statement on IPCC principles and procedures. February 2, 2010. Available at : 

http://www.ipcc.ch/pdf/press/ipcc-statement-principles-procedures-02-2010.pdf. 

Accessed July 23, 2010. 

77 
IPCC (2010c). Organization. Available at: http://www.ipcc.ch/organization/organization.htm. 

Accessed July 23, 2010. 

IPCC (2010d). Errata. In: Climate change 2007: impacts, adaptation and vulnerability. 

Contribution of Working Group II to the Fourth Assessment Report of the 

Intergovernmental Panel on Climate Change [M.L. Parry, O.F. Canziani, J.P. Palutikof, 

P.J. van der Linden, and C.E. Hanson (eds.)]. Cambridge University Press, Cambridge, 

UK. Available at: http://www.ipcc.ch/publications_and_data/ar4/wg2/en/errata.html. 

Accessed July 23, 2010. 

IPCC (2010e). IPCC statement on trends in disaster losses. (January 25, 2010). Available at: 

http://www.ipcc.ch/pdf/presentations/statement_25_01_2010.pdf. Accessed July 23, 

2010. 

IPCC (2010f). IPCC Statement on the Melting of Himalayan Glaciers, January 20, 2010. 

http://www.ipcc.ch/pdf/presentations/himalaya-statement-20january2010.pdf. 

IPCC (2007a). Fourth Assessment Report: Climate Change 2007. Cambridge University Press, 

Cambridge, UK, and New York, NY, USA. 

IPCC (2007b). Climate change 2007: synthesis report. Contribution of Working Groups I, II, and 

III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change 

[core writing team, R.K. Pachauri and A. Reisinger (eds.)]. IPCC, Geneva, Switzerland. 

104 pp. 

IPCC (2007c). Summary for policymakers. In: Climate change 2007: impacts, adaptation and 

vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the 

Intergovernmental Panel on Climate Change [M.L. Parry, O.F. Canziani, J.P. Palutikof, 

P.J. van der Linden, and C.E. Hanson (eds.)]. Cambridge University Press, Cambridge, 

UK. pp. 7–22. 

IPCC (2007d). Summary for policymakers. In: Climate change 2007: mitigation. Contribution of 

Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on 

Climate Change [B. Metz, O.R. Davidson, P.R. Bosch, R. Dave, L.A. Meyer (eds.)]. 

Cambridge University Press, Cambridge, UK, and New York, NY, USA. 

IPCC (2007e). Climate change 2007: the physical science basis. Contribution of Working Group 

I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [S. 

Solomon, D. Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor, and H.L. 

Miller (eds.)]. Cambridge University Press, Cambridge, UK, and New York, NY, USA. 

IPCC (2007f). Appendix III. In: Climate change 2007: impacts, adaptation and vulnerability. 

Contribution of Working Group II to the Fourth Assessment Report of the 

Intergovernmental Panel on Climate Change [M.L. Parry, O.F. Canziani, J.P. Palutikof, 

P.J. van der Linden, and C.E. Hanson (eds.)]. Cambridge University Press, Cambridge, 

78 
UK, and New York, NY, USA. Available at: http://www.ipcc.ch/pdf/assessmentreport/ar4/wg2/ar4-wg2-app.pdf. Accessed July 23, 2010. 

IPCC (2007g). Climate change 2007: impacts, adaptation and vulnerability. Contribution of 

Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on 

Climate Change [M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden, and C.E. 

Hanson (eds.)]. Cambridge University Press, Cambridge, UK, and New York, NY, USA. 

IPCC (2007h). Summary for Policymakers. In: Climate Change 2007: The Physical Science 

Basis. Contribution of Working Group I to the Fourth Assessment Report of the 

Intergovernmental Panel on Climate Change [Solomon, S., D. Qin, M. Manning, Z. 

Chen, M. Marquis, K.B. Averyt, M.Tignor and H.L. Miller (eds.)]. Cambridge University 

Press, Cambridge, United Kingdom and New York, NY, USA. 

IPCC (2006a). Working Group I Fourth Assessment Report review comments and responses. 

Available at: http://hcl.harvard.edu/collections/ipcc/index.html. Accessed July 23, 2010. 

IPCC (2006b). Guidelines for inclusion of recent scientific literature in the Working Group I 

Fourth Assessment Report. Available at: 

http://web.archive.org/web/20070206012931/ipccwg1.ucar.edu/wg1/docs/PublicationDeadlines_2006-07-01.pdf. Accessed July 23, 2010. 

IPCC (2006c). Expert review comments on WGII Fourth Assessment Report: climate 

change impacts, adaptation and vulnerability: Available at: http://ipccwg2.gov/AR4/SOD_COMMS/Ch01_SOD_Expert.pdf. Accessed July 23, 2010. 

IPCC (2005). Deadlines for literature cited in the Working Group I Fourth Assessment Report. 

Available at: http://web.archive.org/web/20060430074956http://ipccwg1.ucar.edu/wg1/docs/PublicationDeadlines.pdf. Accessed July 23, 2010. 

IPCC (2001). Third Assessment Report: Climate Change 2001. Cambridge University Press, 

Cambridge, UK, and New York, NY, USA. 

IPCC (1999). Procedures for the preparation, review, acceptance, adoption, approval, and 

publication of IPCC reports. Adopted at the Fifteenth Session of the IPCC (San Jose, 15–

18 April 1999) and revised, on a provisional basis, at the Twentieth Session of the IPCC 

(Paris, 19–21 February 2003). Available at: 

http://www.climatescience.gov/Library/ipcc/app-a.pdf. Accessed July 23, 2010. 

IPCC (1995). Second Assessment Report: Climate Change 1995. Cambridge University Press, 

Cambridge, UK, and New York, NY, USA. 

Jansen, E., J. Overpeck, K.R. Briffa, J.C. Duplessy, F. Joos, V. Masson-Delmotte, D. Olago, B. 

Otto-Bliesner, W.R. Peltier, S. Rahmstorf, R. Ramesh, D. Raynaud, D. Rind, O. 

Solomina, R. Villalba, and D. Zhang (2007). Palaeoclimate. In: Climate change 2007: the 

physical science basis. Contribution of Working Group I to the Fourth Assessment 

79 
Report of the Intergovernmental Panel on Climate Change [S. Solomon, D. Qin, M. 

Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor, and H.L. Miller (eds.)]. 

Cambridge University Press, Cambridge, UK, and New York, NY, USA. 

Karl, T., J. Melillo, and T. Peterson (eds.) (2009). Global climate change impacts in the United 

States. Cambridge University Press, Cambridge, UK. 

Kingdom of Morocco (2001). First National Communication: United Nations Framework 

Convention on Climate Change. Available at: 

http://unfccc.int/resource/docs/natc/mornc1e.pdf. Accessed July 23, 2010. 

Kretzmann, S. (2010). Africagate is no scandal say IPCC authors. Cape West News. (February 

15, 2010). Available at: http://westcapenews.com/?p=1306. Accessed July 23, 2010. 

Kundzewicz, Z.W., et al. (2007). Freshwater resources and their management. In: Climate 

change 2007: impacts, adaptation and vulnerability. Contribution of Working Group II to 

the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [M.L. 

Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden, and C.E. Hanson (eds.)]. 

Cambridge University Press, Cambridge, UK, and New York, NY, USA. 

Kunseler, E. (2007). Towards a new paradigm of science in scientific policy advising. Available 

at: http://www.nusap.net/downloads/KunselerEssay2007.pdf. Accessed July 23, 2010. 

Landsea, C. (2005). An open letter to the community from Chris Landsea (resignation letter of 

Chris Landsea from IPCC). Available at: 

http://www.climatechangefacts.info/ClimateChangeDocuments/LandseaResignationLette

rFromIPCC.htm. Accessed July 23, 2010. 

Leake, J. (2010a). Africagate: top British scientist says UN panel is losing credibility. Times 

Online. Available at: 

http://www.timesonline.co.uk/tol/news/environment/article7017907.ece. Accessed July 

23, 2010. 

Leake (2010b). UN climate panel shamed by bogus rainforest claim. Available at: 

http://www.damtp.cam.ac.uk/user/jono/pub/cc/pccst/Leake_and_North_original_S_Times_article_31_Jan_2010.pdf. Accessed July 23, 

2010. 

Lemke, K., et al. (2007). Observations: changes in snow, ice and frozen ground. In: Climate 

change 2007: the physical science basis. Contribution of Working Group I to the Fourth 

Assessment Report of the Intergovernmental Panel on Climate Change [S. Solomon, D. 

Qin, M. Manning, Z. Chen, M. Marquis, K.B. Averyt, M. Tignor, and H.L. Miller (eds.)]. 

Cambridge University Press, Cambridge, UK, and New York, NY, USA. 

80 
McKitrick, R.R., and P.J. Michaels (2004). A test of corrections for extraneous signals in gridded 

surface temperature data. Clim. Res. 26(2): 159–173. (Erratum: Clim. Res. 27(3): 265–

268, 2004.) 

Ministry of Territory Development and Environment (2001). Elaboration de la stratégie et du 

plan d’action national des changements climatiques (in French). Available at: 

http://unfccc.int/resource/docs/natc/algnc1.pdf. Accessed July 23, 2010. 

Muir-Wood, R., S. Miller, and A. Boissonade (2006). The search for trends in a global catalogue 

of normalized weather-related catastrophe losses. Workshop on climate change and 

disaster losses: Understanding and attributing trends and projections. Final Workshop 

Report, 25–26. Hohenkammer, Germany. Available at: 

http://sciencepolicy.colorado.edu/sparc/research/projects/extreme_events/munich_worksh

op/workshop_report.html. Accessed July 23, 2010. 

National Academies (2006). Joint Committee Appointment Process. Washington, DC. Available 

at: 

http://www8.nationalacademies.org/cp/information.aspx?key=Committee_Appointment. 

Accessed July 23, 2010. 

Nepstad, D. (2010). Senior Scientist Daniel Nepstad endorses the correctness of the IPCC’s 

(AR4) statement on Amazon forest susceptibility to rainfall reduction Available at: 

http://www.whrc.org/resources/essays/pdf/2010-02-Nepstad_Amazon.pdf. Accessed July 

23, 2010. 

Nepstad, D., I. Tohver, D. Ray, P. Moutinho, and G. Cardinot (2007). Mortality of large trees 

and lianas following experimental drought in an Amazon forest. Ecology (889): 2259–

2269. 

Nepstad, D., P. Lefebvre, U. Lopes da Silva, J. Tomasella, P. Schlesinger, L. Solorzano, P. 

Moutinho, D. Ray, and J. Guerreira Benito (2004). Amazon drought and its implications 

for forest flammability and tree growth: a basin-wide analysis. Global Change Biology 

10: 704–717. 

Nepstad, D.C., et al. (1999). Large-scale impoverishment of Amazonian forests by logging and 

fire. Nature 398: 505–508. 

Nepstad, D., C. Reis de Carvalho, E. Davidson, P. Jipp, P. Lefebvre, G. Hees Negreiros, E. Silva, 

T. Stone, S. Trumbore, and S. Vieira (1994). The role of deep roots in the hydrologic and 

carbon cycles of Amazonian forests and pastures. Nature 372: 666–669. 

81 
Nicholls, R.J., et al. (2007). Coastal systems and low-lying areas. In: Climate 2007: impacts, 

adaptation and vulnerability. Contribution of Working Group II to the Fourth Assessment 

Report of the Intergovernmental Panel on Climate Change [M.L. Parry, O.F. Canziani, 

J.P. Palutikof, P.J. van der Linden, and C.E. Hanson (eds.)]. Cambridge University Press, 

Cambridge, UK, and New York, NY, USA. 

Nicholson, S. (2005). On the question of the “recovery” of the rains in the West African Sahel. 

Journal of Arid Environments 63: 615–641. 

North, R. (2010). And now for Africagate. Available at: 

http://eureferendum.blogspot.com/2010/02/and-now-for-africagate.html. Accessed July 

23, 2010. 

NRC (2006). Surface temperature reconstructions for the last 2,000 years. National Research 

Council. National Academy Press, Washington, DC. 

Olsson, L., L. Eklundh, and J. Ardo (2005). A recent greening of the Sahel—trends, patterns and 

potential causes. Journal of Arid Environments 63: 556–566. 

Parry, M., C. Rosenzweig, and M. Livermore (2005). Climate change, global food supply and 

risk of hunger. Philos. T. Roy. Soc. B 360: 2125–2138. 

PBL (2010a). Assessing an IPCC assessment: an analysis of statements on projected regional 

impacts in the 2007 report. Netherlands Environmental Assessment Agency (PBL). 

Available at: http://www.pbl.nl/images/500216002_tcm61-48119.pdf. Accessed July 23, 

2010. 

PBL (2010b). Correction wording floods risks for the Netherlands in IPCC report. Available at: 

http://www.pbl.nl/en/dossiers/Climatechange/content/correction-wording-floodrisks.html. Accessed July 23, 2010. 

Pielke, R., Jr. (2010a). What does Pielke think about this? Available at: 

http://rogerpielkejr.blogspot.com/2010/01/what-does-pielke-think-about-this.html. 

Accessed July 23, 2010. 

Pielke, R., Jr. (2010b). Do sloppy policy arguments matter? Part 1. Available at: 

http://rogerpielkejr.blogspot.com/2009/12/do-sloppy-policy-arguments-matter-part.html. 

Accessed July 23, 2010. 

Pielke, R.A., Jr., J. Gratz, C.W. Landsea, D. Collins, M.A. Saunders, and R Musulin (2008). 

Normalized hurricane damage in the United States: 1900–2005. Natural Hazards Review 

9: 29–42. 

Pielke, R. Jr. (2006). Disasters, death, and destruction: making sense of recent calamities. 

Oceanography 19(2): 138–147. June 2006. Workshop at Seventh Annual Roger Revelle 

Commemorative Lecture. 

82 
Pile, B. (2010). More laundered literature: a guest post by Ben Pile. Available at:

http://rogerpielkejr.blogspot.com/2010/01/more-laundered-literature-guest-post-by.html. 

Accessed July 23, 2010. 

Ren, J. et al. (2004). Glacier variations and climate warming and drying in the central Himalayas. 

Chin. Sci. Bull. 49(1): 65–69. 

Republic of Tunisia (2001). Initial communication of Tunisia under the United Nations 

Framework Convention on Climate Change. Available at:

http://unfccc.int/resource/docs/natc/tunnc1esum.pdf. Accessed July 23, 2010. 

Reuters (2010). U.N. climate panel admits Dutch sea level flaw. (February 13, 2010). Available 

at: http://www.reuters.com/article/idUSTRE61C1V420100213. Accessed July 23, 2010. 

RMS (2010). RMS FAQ: research on climate change and disaster loss costs and the IPCC. Risk 

Management Solutions, Inc. http://www.rms.com/Publications/2010_FAQ_IPCC.pdf. 

Accessed July 23, 2010. 

Rosenzweig, C., et al. (2007). Assessment of observed changes and responses in natural and 

managed systems. In: Climate change 2007: impacts, adaptation and vulnerability.

Contribution of Working Group II to the Fourth Assessment Report of the 

Intergovernmental Panel on Climate Change [M.L. Parry, O.F. Canziani, J.P. Palutikof, 

P.J. van der Linden, and C.E. Hanson (eds.)]. Cambridge University Press, Cambridge, 

UK. pp. 79–131. 

Rowell, A., and P.F. Moore (2000). Global review of forest fires. World Wildlife Federation and 

The World Conservation Union. Available at: http://data.iucn.org/dbtw-wpd/edocs/2000-

047.pdf. Accessed July 23, 2010. 

Russell, M. (2010). The independent climate change email review. University of East Anglia. 

Available at: http://www.cce-review.org/pdf/FINAL%20REPORT.pdf. Accessed July 23, 

2010. 

Schneeberger, C., H. Blatter, A. Abe-Ouchi, and M. Wild (2003). Modelling changes in the mass 

balance of glaciers of the northern hemisphere for a transient 2* CO2 scenario. J. Hydrol. 

282: 145–163. 

Seaquist, J.W., T. Hickler, L. Eklundh, J. Ardö, and B.W. Heumann (2009). Disentangling the 

effects of climate and people on Sahel vegetation dynamics. Biogeosciences 6: 469–477. 

Available at: http://www.biogeosciences.net/6/469/2009/bg-6-469-2009.pdf. Accessed 

July 23, 2010. 

Solomina, O., R. Barry, and M. Bodnya (2004). The retreat of Tien Shan glaciers (Kyrgyzstan) 

since the Little Ice Age estimated from aerial photographs, lichonometric and historical 

data. Geografiska Annaler 86A(2): 205–215. 

83 
84 

Su, Z., and Shi, Y. (2002). Response of monsoonal temperate glaciers to global warming since 

the Littel Ice Age. Quat. Int. 97–98, 123–131. 

Sunday Times (2010). Retraction on UN climate panel shamed by bogus rainforest claim. the 

Retraction to this article available to subscribers only. Available at: 

http://www.damtp.cam.ac.uk/user/jono/pub/cc/pccst/Leake_and_North_original_S_Times_article_31_Jan_2010.pdf. Accessed July 23, 

2010. 

Taylor, J.M. (2005). Climate scientist quits IPCC, blasts politicized “preconceived agendas.” 

Available at: 

http://www.heartland.org/full/16806/Climate_Scientist_Quits_IPCC_Blasts_Politicized_

Preconc%20eived_Agendas.html. Accessed July 23, 2010. 

Trenberth, K.E., P.D. Jones, P. Ambenje, R. Bojariu, D. Easterling, A. Klein Tank, D. Parker, F. 

Rahimzadeh, J.A. Renwick, M. Rusticucci, B. Soden, and P. Zhai (2007). Observations: 

surface and atmospheric climate change. In: Climate change 2007: the physical science 

basis. Contribution of Working Group I to the Fourth Assessment Report of the 

Intergovernmental Panel on Climate Change [S. Solomon, D. Qin, M. Manning, Z. Chen, 

M. Marquis, K.B. Averyt, M. Tignor and H.L. Miller (eds.)]. Cambridge University 

Press, Cambridge, UK, and New York, NY, USA. 

U.S. EPA (2009). Technical Support Document for endangerment and cause or contribute 

findings for greenhouse gases under Section 202(a) of the Clean Air Act. U.S. 

Environmental Protection Agency, Washington, DC. 

U.S. EPA (2002). Guidelines for ensuring and maximizing the quality, objectivity, utility, and 

integrity of information disseminated by the Environmental Protection Agency. 

Washington, DC: U.S. Environmental Protection Agency. EPA/260/R-02/008. 

Wahl, E., and C. Ammann (2007). Robustness of the Mann, Bradley, Hughes reconstruction of 

Northern Hemisphere surface temperatures: examination of criticisms based on the nature 

and processing of proxy climate evidence. Climatic Change 85: 33–69. 

Wegman, E.J. (2006). Testimony of Edward J. Wegman before the U.S. House Committee on 

Energy and Commerce, July 19, 2006. 

http://republicans.energycommerce.house.gov/108/home/07142006_Wegman_Report.pdf

. Accessed July 23, 2010.