Endangerment and Cause or 

Contribute Findings for 

Greenhouse Gases Under 

Section 202(a) of the Clean Air 

Act: 

EPA’s Response to Public 

Comments 

Volume 1: General Approach to 

the Science and Other 

Technical Issues
General Approach to the Science 

and Other Technical Issues 

U.S. Environmental Protection Agency 

Office of Atmospheric Programs 

Climate Change Division 

Washington, D.C. 
FOREWORD 

This document provides responses to public comments on the U.S. Environmental Protection Agency’s 

(EPA’s) Proposed Endangerment and Cause or Contribute Findings for Greenhouse Gases Under Section 

202(a) of the Clean Air Act, published at 74 FR 18886 (April 24, 2009). EPA received comments on 

these Proposed Findings via mail, e-mail, and facsimile, and at two public hearings held in Arlington, 

Virginia, and Seattle, Washington, in May 2009. Copies of all comment letters submitted and transcripts 

of the public hearings are available at the EPA Docket Center Public Reading Room, or electronically 

through http://www.regulations.gov by searching Docket ID EPA-HQ-OAR-2009-0171. 

This document accompanies the Administrator’s final Endangerment and Cause or Contribute Findings 

for Greenhouse Gases Under Section 202(a) of the Clean Air Act (Findings) and the Technical Support 

Document (TSD), which contains the underlying science and greenhouse gas emissions data. 

EPA prepared this document in multiple volumes, with each volume focusing on a different broad 

category of comments on the Proposed Findings. This volume of the document provides responses to 

public comments regarding the general approach to the science and other technical issues. 

In light of the very large number of comments received and the significant overlap between many 

comments, this document does not respond to each comment individually. Rather, EPA summarized and 

provided a single response to each significant argument, assertion, and question contained within the 

totality of comments. Within each comment summary, EPA provides in parentheses one or more lists of 

Docket ID numbers for commenters who raised particular issues; however, these lists are not meant to be 

exhaustive and EPA does not individually identify each and every commenter who made a certain point in 

all instances, particularly in cases where multiple commenters expressed essentially identical arguments. 

Several commenters provided additional scientific literature to support their arguments. EPA’s general 

approach for taking such literature into consideration is described in Volume 1, Section 1.1, of this 

Response to Comments document. As with the comments, there was overlap in the literature received. 

EPA identified the relevant literature related to the significant comments, and responded to the significant 

issues raised in the literature. EPA does not individually identify each and every piece of literature 

(submitted or incorporated by reference) that made a certain point in all instances. 

Throughout this document, we provide a list of references at the end of each volume for additional 

literature cited by EPA in our responses; however, we do not repeat the full citations of literature cited in 

the TSD. 

EPA’s responses to comments are generally provided immediately following each comment summary. In 

some cases, EPA has discussed responses to specific comments or groups of similar comments in the 

Findings. In such cases, EPA references the Findings rather than repeating those responses in this 

document. 

Comments were assigned to specific volumes of this Response to Comments document based on an 

assessment of the principal subject of the comment; however, some comments inevitably overlap multiple 

subject areas. For this reason, EPA encourages the public to read the other volumes of this document 

relevant to their interests. 

iii 
TABLE OF CONTENTS

1.0 General Approach to the Science and Other Technical Issues 

1.1 Use of IPCC, CCSP, USGCRP, and NRC Reports as the Primary 

 Scientific Basis...........................................................................................................1 

1.1.1 Specific Comments on EPA’s Use of IPCC Reports 

1.1.2 Specific Comments on EPA’s Use of CCSP and USGCRP Reports 

1.2 Level of Scientific Certainty ....................................................................................32 

1.3 Treatment of Adaptation and Emissions Mitigation .............................................46 

1.4 Consideration of Net (Adverse and Beneficial) Effects........................................51 

1.5 Information Quality Act Discussion .......................................................................52 

Appendix A: IPCC Principles and Procedures.......................................................................66 

Appendix B: USGCRP/CCSP Procedures and Responsibilities...........................................88 

Appendix C: NRC Report Development Procedures ...........................................................118 

Acronyms and Abbreviations 

ANPR Advance Notice of Proposed Rulemaking 

AR4 Fourth Assessment Report 

CAA Clean Air Act 

CCSP U.S. Climate Change Science Program 

CO2 carbon dioxide 

CRU Climate Research Unit 

EPA U.S. Environmental Protection Agency 

IPCC Intergovernmental Panel on Climate Change 

IQA Information Quality Act 

GHG greenhouse gases 

NIPCC Nongovernmental International Panel on Climate Change 

NOAA National Oceanic and Atmospheric Administration 

NRC National Research Council 

RCF Request for Correction 

SAP synthesis and assessment product 

SDWA Safe Drinking Water Act 

SPM Summary for Policymakers 

TSD Technical Support Document 

USGCRP U.S. Global Change Research Program

iv 
1.0 General Approach to the Science and Other Technical Issues 

1.1. Use of IPCC, CCSP, USGCRP, and NRC Reports as the Primary Scientific Basis 

Comment (1-1): 

A large number of commenters (0309.1, 0322, 0487, 0499, 0509, 0538, 0664, 0708.1, 0798, 0800.1, 

0921, 1005.1, 1309.1, 1616.1, 1924, 1927, 1961, 2697.1, 2759, 2813.1, 2895, 2898.1, 2916.1, 2972.1, 

3013, 3053, 3136.1, 3145.1, 3187.5, 3219.1, 3224, 3250, 3252.1, 3286.1, 3291.1, 3303, 3307.1, 3316.1, 

3323.1, 3330.1, 3372.1, 3373, 3379.1, 3389, 3394.1, 3397, 3407, 3423.2, 3427.1, 3433.1, 3440.1, 3446.1, 

3446.3, 3449.1, 3452.1, 3473.1, 3497.1, 3533.1, 3548.1, 3560.1, 3567.1, 3596.1, 3596.2, 3603.1, 3630.1, 

3681.1, 3702.1, 3707.1, 3722, 3729.1, 3747.1, 3748.1, 3764.1, 3915, 4003, 4032, 4041.1, 4172, 4288, 

4446, 4509, 4932.1, 5158, 9061.1, 9680, 9863, 9970, 10158, 10160, 10524, 10956, 11029, 11288, 11315, 

11335, A18, 11410, 11466.1, and 11493) generally argued that EPA inappropriately relied almost 

exclusively on information from the assessment literature in developing the Technical Support Document 

(TSD). The commenters said that in taking this approach EPA failed to use the best available science and 

consider other important studies related to the topics presented in the TSD. 

Response (1-1): 

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. Please see responses to comments in this section 

regarding specific issues raised by commenters related to this general comment. 

EPA recognizes that scientific research is very active in many areas addressed in this document. Many 

commenters sent scientific articles, reports, and synthesis studies to the EPA as part of their technical and 

scientific comments. These submissions were categorized as either ‘submitted reference material’ or 

‘materials incorporated by reference.’ Submitted reference materials are those materials that commenters 

provided with their comments. Materials incorporated by reference are those materials that were referred 

to in comments (e.g., article and report titles, book titles, or website links) but that were not submitted to 

EPA. EPA made every effort to retrieve and review publicly available (i.e., available free of charge via 

the internet or standard library access) materials incorporated by reference, particularly those in the peer 

reviewed literature yet not in the peer reviewed assessment literature. 

As noted in the Foreword to each volume of the Response to Comments document, EPA did not 

individually respond to each submitted comment. Instead, we grouped similar comments together and 

addressed them: 

In light of the very large number of comments received and the significant overlap between many 

comments, this document does not respond to each comment individually. Rather, EPA 

summarized and provided a single response to each significant argument, assertion, and question 

contained within the totality of comments. Within each comment summary, EPA provides in 

parentheses one or more lists of Docket ID numbers for commenters who raised particular issues; 

however, these lists are not meant to be exhaustive and EPA does not individually identify each 

and every commenter who made a certain point in all instances, particularly in cases where 

multiple commenters expressed essentially identical arguments. 

Similarly, we did not individually respond to each and every piece of literature submitted or incorporated 

by reference in comments. As explained in the Foreword: 

As with the comments, there was overlap in the literature received. EPA identified the relevant 

literature related to the significant comments, and responded to the significant issues raised in the 

1 
literature. EPA does not individually identify each and every piece of literature (submitted or 

incorporated by reference) that made a certain point in all instances. 

We categorized the literature we received for purposes of its consideration depending on whether or not it 

was peer-reviewed, and, if so whether it was referenced in the assessment literature summarized in the 

TSD. We considered such literature as having already been incorporated into the peer-reviewed 

assessment literature. In many cases, we note this in our response to comments, and in some cases we also 

discuss such literature in our responses if it provides important additional detail or information. If peerreviewed literature was not referenced in the assessment reports, we addressed the major findings in the 

relevant comment response. As noted above, this does not imply that every specific piece of literature 

related to a particular issue was mentioned in that comment response. We also reviewed the literature that 

was not peer-reviewed when responding to significant comments. In many cases we discussed the 

findings or assertions of such literature in our comment responses, but noted that the literature was not 

peer-reviewed, and it was accorded less weight as a result. 

The Agency recognizes the potential importance of new scientific research, and we note within this 

Response to Comments document where new scientific information (from either new assessment reports 

or individual studies) reinforce, refine, or correct specific issues summarized within the TSD. Together, 

the updated final TSD and EPA’s responses to public comments (contained in the Findings and the 11 

volumes of the Response to Comments document) constitute the scientific summary on which the 

Administrator has made her determination. We note that many valuable insights were obtained through 

the review of comments as reflected in the Findings, the TSD, and the Response to Comments document. 

However, we did not identify specific issues or new literature that alters, in a significant way, our 

understanding of how greenhouse gas emissions affect the climate and how climate change may 

reasonably be anticipated to endanger public health or welfare. 

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 “cherry-picking” 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 precisely to avoid an over-reliance 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 

2 
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 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.” 

3 
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. 

Comment (1-3): 

Several commenters (2895, 2916.1, 3145.1, 3330.1, 3497.1, 3533.1, 3630.1, 3747.1, and 10524) argue 

that EPA cherry-picked specific studies from the scientific literature in making its conclusions. 

Response (1-3): 

EPA disagrees with the comment that the Agency selectively chose studies to serve as the basis for the 

endangerment finding, as addressed in our response to comment 1-2. 

Comment (1-4): 

A large number of commenters (0245, 0636, 0655, 2898.1, 2972.1, 3145.1, 3187.1, 3214.2, 3224, 3316.1, 

3323.1, 3347.4, 3360, 3373, 3394.1, 3397, 3423.2, 3427.1, 3433.1, 3440.1, 3452.1, 3482.1, 3533.1, 3597, 

3630.1, 3681.1, 3722, 3729.1, 3747.1, 4003, 4041.1, 4168, 4172, 4932.1, 5158, 7020, 9060.1, 9680, 9863, 

10158, 10577, 10956, 11046, and 11165) argue that EPA should have conducted its own assessment of 

climate data and research in developing the Proposed Findings, instead of relying on the body of 

assessment literature. The commenters argue that the assessment reports do not represent the best 

available science for a number of reasons, including inappropriate review process, failure to meet 

information quality guidelines, etc. Commenter 3567.1 states that for the Proposed Findings, EPA should 

have commissioned a body of independent scientists, engineers, and statisticians to evaluate the data, 

methods, and conclusions of the most important research. 

Response (1-4): 

See Section III.A. of the Findings, “The Science on Which the Decisions Are Based,” for our rationale on 

the approach to the scientific literature and our decision that it was not necessary nor logical for EPA to 

conduct an additional and separate review of the underlying climate data and research. We respond to the 

specific comments regarding the assessment literature (e.g., inappropriate review process) and the 

information quality guidelines separately below. 

Comment (1-5): 

A commenter (11458) argues that technically and traditionally, EPA has no purview or expertise in any of 

the various areas of concern cited in the Proposed Findings (i.e. storms, droughts, sea levels, crop yields, 

etc.). The commenter states that climate change is not an issue where there is some dose-dependent 

biological response to a traditional pollutant; it is a “complex physical response (complete with positive 

and negative feedback) by an entire planet!” The commenter states that because EPA “necessarily has 

limited expertise, knowledge base, or experience” in these areas, it is inappropriate for EPA to move 

forward with the Findings. 

Response (1-5): 

We disagree with the commenter’s assertion that EPA does not have purview or expertise in the climate 

science issues discussed in the TSD. As stated in the Findings, EPA has been a very active part of the 

United States Government climate change research enterprise, and has taken an active role in the 

reviewing, writing, and approval of the USGCRP/CCSP assessment reports. EPA was the lead agency for 

three significant reports under the USGCRP and recently completed an assessment addressing the climate 

change impacts on air quality in the United States. EPA was also involved in a review of the IPCC Fourth 

4 
Assessment Report (AR4), and in particular took part in the approval of the summary for policymakers 

for the Working Group II volume, Impacts, Adaptation, and Vulnerability. We note that the specific 

climate science issues raised by the commenter (e.g., storms, droughts, sea levels, crop yields) and the 

positive/negative feedbacks are all covered in great detail within these assessment reports. 

We did not develop new science to support the finding, but rather relied primarily on the conclusions of 

the major assessment reports of USGCRP/CCSP, IPCC, and NRC and the evaluation of the public 

comments received. See Section III.A. of the Findings, “The Science on Which the Decisions Are Based,” 

for our response to comments on the rationale for our use of the assessment literature. The use of the 

assessment literature capitalizes on the substantial expertise and experience that went into the 

development of those reports. No other source of information provides such a comprehensive and indepth analysis across such a large body of scientific studies. 

Comment (1-6): 

Several commenters (3252.1, 3286.1, 3379.1, 3394.1, 3449.1, 3705.1 and 3579.1) argue that the TSD 

relies upon sources of information that do not adequately address the scientific issues relevant under the 

Clean Air Act (CAA), because the IPCC assessment reports do not address United States–specific effects 

in isolation, were published several years ago, and do not follow information quality guidelines. 

Response (1-6): 

See EPA’s responses in this volume which address the comments regarding the geographic scope of 

IPCC’s findings, the timeliness and relevancy of these reports, and their consistency with information 

quality guidelines. 

The endangerment analysis for greenhouse gases under the CAA requires that EPA examine the extent to 

which the GHGs constitute the air pollution that may be reasonably anticipated to endanger public health 

or welfare. Please refer to Section IV.A. of the Findings (“The Air Pollution Consists of Six Key 

Greenhouse Gases”) for the Administrator’s rationale as to why the six well-mixed GHGs are defined as 

the air pollution for purposes of the endangerment finding under Section 202(a) of the CAA. The 

Findings discuss in detail the information that is relevant to the determination and how the Administrator 

has interpreted it in deciding whether the air pollution is reasonably anticipated to endanger public health 

or welfare. The scientific literature as synthesized in the TSD provides exactly the kind of information 

that can help inform these issues. For example, the TSD summarizes the conclusions of the assessment 

reports with respect to: 1) current emissions of GHG emissions; 2) how these emissions are changing the 

composition of the atmosphere; 3) how such changes in the atmosphere are affecting the global and 

regional climate; and 4) the potential impacts of such changes in climate on human health and welfare, for 

current and future generations. In its scope and quality, the assessment literature is relevant and 

appropriate for addressing the scientific issues under the CAA. Furthermore, the most recent study from 

the assessment literature and synthesized in the TSD was released in June, 2009. That study, Karl et al. 

(2009), provides both U.S.-focused information as well as re-affirms many of the key findings from the 

assessment literature from previous years (e.g., 2007). 

Comment (1-7): 

A commenter (4529) argues that the assessment reports on climate change used by EPA do not follow the 

scientific method and therefore provide an inappropriate basis for making an endangerment finding. 

Response (1-7): 

5 
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. 

We disagree with the commenter’s general claim that the assessment reports on climate change do not 

follow the scientific method. EPA notes that the comment did not provide specific examples or other 

support for this assertion, nor did the commenter provide detail as to how the assessment literature does 

not follow the scientific method. We are aware of no evidence to support the commenter’s charge. To the 

contrary, EPA has found that the assessment reports appropriately applied the scientific method by using 

multiple lines of climate science evidence to formulate and test hypotheses, investigate cause and effect 

relationships in observations, and evaluate new knowledge and advancements. 

The assessment reports summarized in the TSD were prepared following rigorous and transparent 

processes addressing such issues as the nomination and selection of authors, the caliber of literature 

reflected in the assessment, and the processes for review and revision of reports. The TSD provides a 

general description of these procedures in Section 1(b), and Box 1.1, and our responses to specific 

comments on these issues are provided in Sections 1.1.1 and 1.1.2 below. 

Comment (1-8): 

At least one commenter (3307.1) asserts that EPA’s “fail[ure] to consider reliable” scientific data made 

available after the publication of the Advance Notice of Proposed Rulemaking (ANPR) “flouts” the 1997 

Report of the Presidential Commission on Risk Assessment and Risk Management. They also assert that 

EPA fails “to appropriately explain and incorporate relevant scientific data” as suggested by the 2009 

Presidential Memorandum on Scientific Integrity. 

Response (1-8): 

EPA has considered all relevant information in the public record for this rulemaking. In its consideration, 

EPA has fully complied with all legal requirements, and has acted consistently with the 1997 report and 

2009 Memorandum commenter cites. We note that the 1997 Report states that assessing risks should 

allow for “incorporation of important new information that may emerge at any stage of the risk 

management process.” The 2009 Memorandum describes that “there should be transparency in the 

preparation, identification, and use of scientific and technological information in policymaking” and that 

the scientific information used in policy decisions “should be subject to well-established scientific 

processes, including peer review where appropriate.” As discussed in the Findings and the Response to 

Comments document, EPA’s approach to the science did allow for the incorporation of important new 

information (e.g., more recent assessment reports and public comment), and followed well-established 

scientific processes (e.g., the assessment reports were peer-reviewed). For a fuller discussion of the 

science considered, as well as the reliability of the science used, please see Section III.A. of the Findings, 

“The Science on Which the Decisions Are Based,” and responses in this section of Volume 1. 

Comment (1-9): 

A commenter (0719) discusses how it is important to recognize that broad assessments, such as IPCC and 

CCSP reports, are too conservative in projecting climate change impacts and typically represent a kind of 

lowest common denominator in scientific judgment. The commenter states that EPA should not always 

wait for science to provide overwhelming certainty and that judgment must be exercised to avoid 

catastrophic risks even when the science is still incomplete. 

Response (1-9): 

6 
EPA notes that through our evaluation of the scientific literature and review of public comments, we have 

determined that the TSD provides a sound foundation for the Administrator’s endangerment analysis. We 

do not find the assessment reports to be too conservative. Rather, we find that they represent the best 

available science because they review and analyze the most recent science and evaluate uncertainties in 

making their conclusions. We received many comments on the legal requirements for the endangerment 

determination, and our response on the issue of whether the Administrator need wait until harm has 

occurred and the precautionary and preventive nature of the statutory language is provided in Section II. 

A. of the Findings, “Legal Framework for this Action.” 

 

Comment (1-10): 

Several commenters (1309.1, 2750, 3187.5, 3316.1, 3394.1, 3440.1, 3548.1, 3729.1, 3747.1, 7020, and 

11459) argue that EPA’s external peer-review process was inadequate because the federal expert 

reviewers were involved with developing the IPCC and CCSP reports upon which the endangerment 

finding is based and therefore not objective. 

Response (1-10): 

EPA disagrees that review of the scientific and technical information contained in the TSD was 

inadequate. EPA did not develop new science as part of this action and instead summarized the existing 

peer-reviewed assessment literature. The decision to have 12 federal experts review the TSD was 

reasonable and appropriate and we disagree that the reviewers were not objective as a result of their 

involvement with the IPCC and CCSP. Given our approach to the scientific literature (described in 

Section III.A of the Findings), 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. Finally, we note that the federal expert review was only one part of a 

much larger process of developing the TSD from 2007 until the present. In addition to the three rounds of 

technical review by the 12 federal experts, the TSD has also gone through three rounds of internal EPA 

review, and two rounds of public comment. 

Comment (1-11): 

Two commenters (3187.5, 3729.1, and 3764.1) argue that EPA should once again review the comments 

received on the TSD for the (ANPR) on Regulating Greenhouse Gases Under the Clean Air Act regarding 

the use of IPCC and CCSP reports. 

Response (1-11): 

EPA received a number of comments specifically focused on the TSD during the 120-day public 

comment period for the 2008 ANPR. We reviewed these comments and revised and updated the version 

of the TSD that was released with the Proposed Findings on endangerment and cause or contribute in 

April 2009. Thus, many of the comments received on the ANPR were reflected in the version of the 

proposal and the TSD released in April 2009, which served as the underlying scientific and technical 

basis for the proposal. For the purposes of this action, EPA has once again reviewed the comments 

received on the ANPR regarding the use of the assessment literature in developing the TSD. Most of these 

comments were also submitted during the notice and 60-day comment period on the Proposed Findings, 

7 
and EPA’s responses to those resubmitted comments are provided in the relevant Response to Comment 

volumes. EPA used an ANPR to notify the public about actions that were broadly being considered and to 

gather information on specific topics and the appropriate scope for potential rulemaking. It is not clear 

whether commenters are suggesting that existing law prescribes such a requirement; however EPA 

disagrees with that interpretation; there is no legal requirement for the Agency to formally respond to 

comments filed on the ANPR and not resubmitted during this public comment period. 

Comment (1-12): 

Several commenters (1924, 2898.1, 3214.1, 3330.1, 3389, 3446.2, 3560.1, 3679.1, 3748.1, 3969.1, and 

4172) argue that EPA should base its endangerment finding on the recent Nongovernmental International 

Panel on Climate Change (NIPCC) report entitled Climate Change Reconsidered, instead of IPCC and 

CCSP reports. 

Response (1-12): 

EPA has reviewed and considered the NIPCC report and found that it lacks the rigorous procedures and 

transparency required to serve as a foundation for the endangerment analysis. A review of the NIPCC 

Web site indicates that the NIPCC report was developed by “two co-authors” and “35 contributors and 

reviewers” from “14 countries” (http://www.nipccreport.org/index.html). The organization does not 

appear to have established any procedures for author selection and provides no evidence that a transparent 

and open public or expert review was conducted. Thus, the NIPCC’s approach stands in sharp contrast to 

the clear, transparent, and open procedures of the IPCC, CCSP, USGCRP, and NRC. Relying on the work 

of the major assessment reports is a sound and reasonable approach. 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 process. 

Although EPA sees no reason to base the endangerment analysis on the NIPCC, we did thoroughly 

review the report and the associated references. For EPA’s responses to comments and literature provided 

on specific climate science issues in the TSD, including the work of the NIPCC, please refer to the 

appropriate Response to Comment volumes. 

Comment (1-13): 

Several commenters (3323.1, 4003, 4041.1, 4932.1, 5158, and 11493) attached the following reference 

document to their comment: Proposed NCEE Comments on the Draft Technical Support Document for 

Endangerment Analysis for Greenhouse Gas Emissions Under the Clear Air Act. This memorandum was 

developed by Alan Carlin in EPA's National Center for Environmental Economics. The commenters 

argue that EPA has accepted the findings reached by outside groups, such as IPCC and CCSP, as being 

correct without undertaking a careful and critical examination of the conclusions and documentation in 

the Carlin document. The document itself and several of the commenters suggest that EPA conduct a 

review of all available climate change science before moving forward with the endangerment finding. 

Response (1-13): 

As noted in our response to Comment 1-1, EPA has reviewed new and additional scientific literature 

received through public comment. This review includes the Carlin document; see the relevant Response 

to Comments volumes for our responses to specific scientific comments raised in that 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 EPA’s decision not to conduct a new and separate 

8 
assessment of the vast body of underlying science. Finally, see Volume 11, Section 11.6.4 (Transparency) 

for our response to further comments regarding the Carlin document. 

1.1.1 Specific Comments on EPA’s Use of IPCC Reports 

Comment (1-14): 

Commenters (1309.1, 2813.1, 3187.5, 3330.1, 3389, 3429.1, 3440.1, 3597, 3722, 4032, 4288, 9061.1, 

10196, 10197, 11288, 11315, 11409, 11046, and 11410) argue that the process and structure that IPCC 

employs in developing its assessment reports yields flawed reports. Specifically, several commenters 

(0664, 3187.5, 3250, 3330.1, 3372.1, and 4172) add that IPCC report development process is not 

transparent. Several of these commenters argue that not all of the authors or governments that participated 

in the report development process agree with all of the conclusions and that consensus was never reached. 

A few commenters (1309.1, 3187.5, and 11409) argue that the IPCC information quality process and 

system for engaging public comments is flawed, as the IPCC ignores the best available science and 

comments that have been submitted during public comment. Several commenters (0582, 1309.1, 3187.5, 

3747.1, 4172, and 11409) argue that the review process IPCC uses is not objective, transparent to the 

public, or effective in ensuring that the best available information is used. 

Response (1-14): 

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 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. 

We refer the commenters to Appendix A of this volume, which contains IPCC’s Principles Governing 

IPCC Work (2006), IPCC’s Procedures for the Preparation, Review, Acceptance, Adoption, Approval, 

and Publication of IPCC Reports (1999), and IPCC’s Guidance Notes for Lead Authors of the IPCC 

Fourth Assessment Report on Addressing Uncertainties (2004). Regarding the role of the IPCC, we quote 

from their Principles (IPCC, 2006) which states that: 

The role of the IPCC is to assess on a comprehensive, objective, open and transparent 

basis the scientific, technical and socio-economic information relevant to understanding 

the scientific basis of risk of human-induced climate change, its potential impacts and 

options for adaptation and mitigation. IPCC reports should be neutral with respect to 

policy. 

EPA has both evaluated and participated in the development and review of IPCC reports, and the IPCC 

process is transparent and rigorous. The IPCC ensures scientific credibility and legitimacy of its reports 

by fairly representing the range of scientific opinions on climate change, and the IPCC provides multiple 

opportunities for input from experts along the entire spectrum of opinions. Public comment periods for 

the three Working Group reports that compose IPCC (2007) were held to provide the international 

community with opportunities to review and comment. In the U.S., the CCSP announced public comment 

opportunities in the Federal Register and on the CCSP Web site (see list of CCSP announcements and FR 

notices at http://www.climatescience.gov/Library/ipcc/default.htm) for each of the IPCC (2007) Working 

Group reports and the Synthesis Report. CCSP also solicited nominations of author and reviewers for the 

IPCC (2007) reports using the same communications vehicles. Finally, IPCC provides the public with 

access to comments received and how they were responded to for transparency purposes. Please see the 

excerpt from IPCC’s Procedures (IPCC, 1999) at the end of this response which describes in detail the 

9 
procedures for author selection, report drafting, review by governments and experts, final report 

preparation, and formal approval and acceptance. Appendix A of this volume contains IPCC’s 

Procedures (IPCC, 1999) in its entirety. 

Regarding the comment that the authors involved in producing IPCC (2007) and the governments charged 

with its review and acceptance did not agree with all of the conclusions, we note that the IPCC has a 

robust and transparent process for reaching consensus and properly documenting instances where 

consensus is not met. IPCC’s Principles (IPCC, 2006) state that: 

In taking decisions, and approving, adopting and accepting reports, the Panel, its 

Working Groups and any Task Forces shall use all best endeavors to reach consensus. If 

consensus is judged by the relevant body not possible: (a) for decisions on procedural 

issues, these shall be decided according to the General Regulations of the WMO; (b) for 

approval, adoption and acceptance of reports, differing views shall be explained and, 

upon request, recorded. Differing views on matters of a scientific, technical or socioeconomic nature shall, as appropriate in the context, be represented in the scientific, 

technical or socio-economic document concerned. Differences of views on matters of 

policy or procedure shall, as appropriate in the context, be recorded in the Report of the 

Session. 

We disagree with the commenter that consensus was not reached amongst the governments and authors 

involved with the IPCC. Consistent with IPCC procedures, the Summary for Policymakers of Working 

Groups I, II, and III were ‘approved’ and the full reports of the three Working Groups were ‘accepted’. 

IPCC Procedures (IPCC, 1999) define ‘approval’ to mean that “the material has been subjected to 

detailed, line by line discussion and agreement,” and “acceptance” signifies that “the material has not 

been subject to line by line discussion and agreement, but nevertheless presents a comprehensive, 

objective and balanced view of the subject matter.” Finally, we note that most of the commenters 

provided no evidence to defend their arguments. The few pieces of evidence that were submitted focused 

on very narrow and specific findings of studies that were referenced by IPCC (2007). For EPA’s 

responses to these specific issues, please refer to the appropriate Response to Comment volumes. 

Below, we provide excerpts of the relevant sections of the IPCC procedures (IPCC, 1999); the full text of 

the procedures is found in Appendix A. 

Report development: To ensure objectivity, transparency, and information quality, the procedures 

(IPCC, 1999) clearly describe the roles and responsibilities of coordinating lead authors, lead authors, 

contributing authors, expert reviewers, review editors, and government reviewers in report development. 

4.2.1 Compilation of Lists of Coordinating Lead Authors, Lead Authors, Contributing 

Authors, Expert Reviewers, Review Editors and Government Focal Points 

At the request of Working Group/Task Force Bureau Co-Chairs through their respective 

Working Group /Task Force Bureau, and the IPCC Secretariat, governments, and 

participating organizations and the Working Group/Task Force Bureau should identify 

appropriate experts for each area in the Report who can act as potential Coordinating 

Lead Authors, Lead Authors, Contributing Authors, expert reviewers or Review Editors. 

To facilitate the identification of experts and later review by governments, governments 

should also designate their respective Focal Points. IPCC Bureau Members and Members 

of the Task Force Bureau should contribute where necessary to identifying appropriate 

Coordinating Lead Authors, Lead Authors, Contributing Authors, expert reviewers, and 

Review Editors in cooperation with the Government Focal Points within their region to 

ensure an appropriate representation of experts from developing and developed countries 

10 
and countries with economies in transition. These should be assembled into lists available 

to all IPCC Members and maintained by the IPCC Secretariat. The tasks and 

responsibilities of Coordinating Lead Authors, Lead Authors, Contributing Authors, 

expert reviewers, Review Editors and government Focal Points are outlined in Annex 1. 

4.2.2 Selection of Lead Authors 

Coordinating Lead Authors and Lead Authors are selected by the relevant Working 

Group/Task Force Bureau, under general guidance and review provided by the Session of 

the Working Group or, in case of reports prepared by the Task Force on National 

Greenhouse Gas Inventories, the Panel, from those experts cited in the lists provided by 

governments and participating organizations, and other experts as appropriate, known 

through their publications and works. The composition of the group of Coordinating Lead 

Authors and Lead Authors for a section or chapter of a Report shall reflect the need to 

aim for a range of views, expertise and geographical representation (ensuring appropriate 

representation of experts from developing and developed countries and countries with 

economies in transition). There should be at least one and normally two or more from 

developing countries. The Coordinating Lead Authors and Lead Authors selected by the 

Working Group/Task Force Bureau may enlist other experts as Contributing Authors to 

assist with the work. 

At the earliest opportunity, the IPCC Secretariat should inform all governments and 

participating organizations who the Coordinating Lead Authors and Lead Authors are for 

different chapters and indicate the general content area that the person will contribute to 

the chapter. 

4.2.3 Preparation of Draft Report 

Preparation of the first draft of a Report should be undertaken by Coordinating Lead 

Authors and Lead Authors. Experts who wish to contribute material for consideration in 

the first draft should submit it directly to the Lead Authors. 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, a hard copy should be archived and the location where such 

material may be accessed should be cited. 

Lead Authors will work on the basis of these contributions, the peer-reviewed and 

internationally-available literature, including manuscripts that can be made available for 

IPCC review and selected non-peer review literature according to Annex 2 and IPCC 

Supporting Material (see section 6). Material which is not published but which is 

available to experts and reviewers may be included provided that its inclusion is fully 

justified in the context of the IPCC assessment process (see Annex 2). 

In preparing the first draft, and at subsequent stages of revision after review, Lead 

Authors should clearly identify disparate views for which there is significant scientific or 

technical support, together with the relevant arguments. Technical summaries provided 

will be prepared under the leadership of the Working Group/Task Force Bureau. 

Review: IPCC’s Procedures prescribe that “Review is an essential part of the IPCC process, to ensure an 

objective and complete assessment of current information.” The following excerpts from IPCC’s 

Procedures describe in detail the steps, requirements, and objectives of the review process. 

11 
4.1 Introduction to Review Process 

The review process generally takes place in three stages: expert review of IPCC Reports, 

government/expert review of IPCC Reports, government review of the Summaries for 

Policymakers, Overview Chapters and/or the Synthesis Report. Working Group/Task 

Force Bureau Co-Chairs should aim to avoid (or at least minimize) the overlap of 

government review periods for different IPCC Reports and with Sessions of the 

Conference of Parties of the United Nations Framework Convention of Climate Change 

and its subsidiary bodies. 

Expert review should normally be eight weeks, but not less than six weeks, except to the 

extent decided by the Panel. Government and government/expert reviews should not be 

less than eight weeks, except to the extent decided by the Panel. 

All written expert, and government review comments will be made available to reviewers 

on request during the review process and will be retained in an open archive in a location 

determined by the IPCC Secretariat on completion of the Report for a period of at least 

five years.... 

...4.2.4 Review 

Three principles governing the review should be borne in mind. First, the best possible 

scientific and technical advice should be included so that the IPCC Reports represent the 

latest scientific, technical and socio-economic findings and are as comprehensive as 

possible. 

Secondly, a wide circulation process, ensuring representation of independent experts (i.e. 

experts not involved in the preparation of that particular chapter) from developing and 

developed countries and countries with economies in transition should aim to involve as 

many experts as possible in the IPCC process. Thirdly, the review process should be 

objective, open and transparent. 

To help ensure that Reports provide a balanced and complete assessment of current 

information, each Working Group/Task Force Bureau should normally select two Review 

Editors per chapter (including the executive summaries) and per technical summary of 

each Report. 

Review Editors should normally consist of a member of the Working Group/Task Force 

Bureau, and an independent expert based on the lists provided by governments and 

participating organizations. Review Editors should not be involved in the preparation or 

review of material for which they are an editor. In selecting Review Editors, the Bureau 

should select from developed and developing countries and from countries with 

economies in transition, and should aim for a balanced representation of scientific, 

technical, and socio-economic views. 

4.2.4.1 First Review (by Experts) 

First draft Reports should be circulated by Working Group/Task Force Bureau Co-Chairs 

for review by experts selected by the Working Group/Task Force Bureau and, in addition, 

those on the lists provided by governments and participating organizations, noting the 

need to aim for a range of views, expertise, and geographical representation. The review 

circulation should include: 

o Experts who have significant expertise and/or publications in particular areas 

covered by the Report. 

12 
o Experts nominated by governments as Coordinating Lead Authors, Lead 

Authors, contributing authors or expert reviewers as included in lists maintained 

by the IPCC Secretariat. 

o Expert reviewers nominated by appropriate organizations. 

The first draft Reports should be sent to Government Focal Points, for information, along 

with a list of those to whom the Report has been sent for review in that country. 

The Working Group/Task Force Bureau Co-Chairs should make available to reviewers 

on request during the review process specific material referenced in the document being 

reviewed, which is not available in the international published literature. 

Expert reviewers should provide the comments to the appropriate Lead Authors through 

the relevant Working Group/Task Force Bureau Co-Chairs with a copy, if required, to 

their Government Focal Point. 

Coordinating Lead Authors, in consultation with the Review Editors and in coordination 

with the respective Working Group/Task Force Bureau Co-Chairs and the IPCC 

Secretariat, are encouraged to supplement the draft revision process by organizing a 

wider meeting with principal Contributing Authors and expert reviewers, if time and 

funding permit, in order to pay special attention to particular points of assessment or 

areas of major differences. 

4.2.4.2 Second Review (by Governments and Experts) 

A revised draft should be distributed by the appropriate Working Group/Task Force 

Bureau Co-chairs or through the IPCC Secretariat to governments through the designated 

Government Focal Points, and to all the coordinating lead authors, lead authors and 

contributing authors and expert reviewers. 

Governments should send one integrated set of comments for each Report to the 

appropriate Working Group/Task Force Bureau Co-chairs through their Government 

Focal Points. 

Non-government reviewers should send their further comments to the appropriate 

Working Group/Task Force Bureau Co-Chairs with a copy to their appropriate 

Government Focal Point. 

Acceptance and Approval: Finally, IPCC’s Procedures (1999) describe the acceptance and approval 

procedures to ensure that the development of the assessment reports has been completed in a way which 

maximizes objectivity, transparency, quality, and utility: 

4.2.5 Preparation of Final Draft Report 

Preparation of a final draft Report taking into account government and expert comments 

for submission to a Session of a Working Group or, in case of a report prepared by the 

Task Force on National Greenhouse Gas Inventories, of the Panel for acceptance should 

be undertaken by Coordinating Lead Authors and Lead Authors in consultation with the 

Review Editors. If necessary, and timing and funding permitting, a wider meeting with 

principal Contributing Authors and expert and government reviewers is encouraged in 

order to pay special attention to particular points of assessment or areas of major 

differences. It is important that Reports describe different (possibly controversial) 

scientific, technical, and socio-economic views on a subject, particularly if they are 

13 
relevant to the policy debate. The final draft should credit all Coordinating Lead Authors, 

Lead Authors, Contributing Authors, reviewers and Review Editors by name and 

affiliation (at the end of the Report). 

4.3 Approval and Acceptance of Summaries for Policymakers and Adoption of 

Overview Chapters of Methodology Reports Related to National Greenhouse Gas 

Inventories 

Summary sections of Reports approved by the Working Groups and accepted by the 

Panel will principally be the Summaries for Policymakers, prepared by the respective 

Working Groups of their full scientific, technical and socio-economic assessments, and 

Summaries for Policymakers of Special Reports prepared by the Working Groups. The 

Summaries for Policy Makers should be subject to simultaneous review by both experts 

and governments and to a final line by line approval by a Session of the Working Group. 

Responsibility for preparing first drafts and revised drafts of Summaries for 

Policymakers, lies with the respective Working Group Co-Chairs. The Summaries for 

Policymakers should be prepared concurrently with the preparation of the main Reports. 

Approval of the Summary for Policymakers at the Session of the Working Group, 

signifies that it is consistent with the factual material contained in the full scientific, 

technical and socioeconomic assessment or Special Report accepted by the Working 

Group. Coordinating lead authors may be asked to provide technical assistance in 

ensuring that consistency has been achieved. These Summaries for Policymakers should 

be formally and prominently described as: 

“A Report of [Working Group X of] the Intergovernmental Panel on Climate 

Change.” 

For a Summary for Policymakers approved by a Working Group to be endorsed as an 

IPCC Report, it must be accepted at a Session of the Panel. Because the Working Group 

approval process is open to all governments, Working Group approval of a Summary for 

Policymakers means that the Panel cannot change it. However, it is necessary for the 

Panel to review the Report at a Session, note any substantial disagreements, (in 

accordance with Principle 10 of the Principles Governing IPCC Work) and formally 

accept it. 

As demonstrated by these procedures, IPCC assessment reports are developed following well-established 

and comprehensive guidelines. As an example of how this process works in practice, the introduction to 

IPCC (2007b), the working group report on impacts, adaptation and vulnerability, summarized their 

process as follows: 

In total, the Working Group II Fourth Assessment involved 48 Coordinating Lead 

Authors (CLAs), 125 Lead Authors (LAs), and 45 Review Editors (REs), drawn from 70 

countries. In addition, there were 183 Contributing Authors and 910 Expert Reviewers. 

Each chapter in the Working Group II Fourth Assessment had a writing team of two to 

four CLAs and six to nine LAs. Led by the CLAs, it was the responsibility of this writing 

team to produce the drafts and finished version of the chapter. Where necessary, they 

could recruit Contributing Authors to assist in their task. Three drafts of each chapter 

were written prior to the production of the final version. Drafts were reviewed in two 

separate lines of review, by experts and by governments. It was the role of the REs (two 

14 
to three per chapter) to ensure that the review comments were properly addressed by the 

authors. 

The authors and REs were selected by the Working Group II Bureau from the lists of 

experts nominated by governments. Due regard was paid to the need to balance the 

writing team with proper representation from developing and developed countries, and 

Economies in Transition. In the review by experts, chapters were sent out to experts, 

including all those nominated by governments but not yet included in the assessment, 

together with scientists and researchers identified by the Working Group II Co-Chairs 

and Vice-Chairs from their knowledge of the literature and the global research 

community. 

The evidence is clear that the IPCC’s procedures are sufficient and effective for ensuring quality, 

transparency, and consideration of multiple and diverse perspectives. Because the assessment reports EPA 

used in developing the TSD represent the best available science, and because supporting studies were 

conducted in accordance with sound and objective scientific practices, were peer reviewed, and adhered 

to standards of quality based on objectivity, utility, and integrity, we find that IPCC’s information quality 

process is consistent with EPA’s Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility 

and Integrity of Information Disseminated by the Environmental Protection Agency. 

The U.S. Government participated fully in the development, review, and ultimate acceptance and 

approval of IPCC (2007). As stated on the USGCRP’s Web site: “When governments accept the IPCC 

reports and approve their Summary for Policymakers, they acknowledge the legitimacy of their scientific 

content” (http://www.globalchange.gov/publications/reports/ipcc-reports). 

Comment (1-15): 

A commenter (3303) argues that the IPCC AR4 relied upon non-peer reviewed, unsupportable studies 

rather than peer-reviewed literature. 

Response (1-15): 

The IPCC Procedures (IPCC, 1999) used in preparing its assessment reports are described above and can 

be viewed in Appendix A of this volume. The IPCC provides a robust process for ensuring that the best 

available scientific information is used in their assessment report development process. The IPCC (2007) 

relied almost exclusively on peer-reviewed, published information and we note that IPCC procedures 

require reliance on peer-reviewed literature except in specific instances. IPCC’s guidelines state that 

“Contributions should be supported as far as possible with references from the peer-reviewed and 

internationally available literature...” (IPCC, 1999). Limited unpublished material was included only if it 

was justified in the context of the IPCC assessment process and completely accessible. 

Annex 2 of the IPCC procedures (IPCC, 1999) provides the following guidelines for using non-published 

sources in assessment reports: 

Because it is increasingly apparent that materials relevant to IPCC Reports, in particular, 

information about the experience and practice of the private sector in mitigation and 

adaptation activities, are found in sources that have not been published or peer-reviewed 

(e.g., industry journals, internal organizational publications, non-peer reviewed reports or 

working papers of research institutions, proceedings of workshops etc) the following 

additional procedures are provided. These have been designed to make all references 

used in IPCC Reports easily accessible and to ensure that the IPCC process remains open 

and transparent. 

15 
1. Responsibilities of Coordinating, Lead and Contributing Authors 

Authors who wish to include information from a non-published/non-peer-reviewed 

source are requested to: 

a. Critically assess any source that they wish to include. This option may be used for 

instance to obtain case study materials from private sector sources for assessment of 

adaptation and mitigation options. Each chapter team should review the quality and 

validity of each source before incorporating results from the source into an IPCC Report. 

b. Send the following materials to the Working Group/Task Force Bureau Co-Chairs who 

are coordinating the Report: 

- One copy of each unpublished source to be used in the IPCC Report 

- The following information for each source: 

- Title 

- Author(s) 

- Name of journal or other publication in which it appears, if applicable 

- Information on the availability of underlying data to the public 

- English-language executive summary or abstract, if the source is written in a nonEnglish language 

- Names and contact information for 1-2 people who can be contacted for more 

information about the source. 

2. Responsibilities of the Review Editors 

The Review Editors will ensure that these sources are selected and used in a consistent 

manner across the Report. 

These procedures establish that the IPCC rely almost exclusively on peer-reviewed literature. The 

procedures also provide a comprehensive, transparent and robust process in the rare circumstances where 

unpublished or non-peer reviewed material is used. Further, EPA’s review of the studies included in the 

IPCC assessment reports, which we used in developing the TSD, confirms that the use of non-peerreviewed literature was predominantly associated with the report of IPCC Working Group III 

(“Mitigation of Climate Change”) and the treatment of adaptation issues in IPCC Working Group II, two 

areas not assessed by the Administrator in this action. See Section III.C, “Adaptation and Mitigation,” of 

the Findings for a discussion on the treatment of adaptation and mitigation. 

The commenter describes two pieces of literature that were referenced by IPCC but not published in peerreviewed 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. 

Comment (1-16): 

Several commenters (e.g., 3680.1, 4101, 4143, 7392, 8318, 8874, 10156) voice their support for EPA’s 

reliance on recently published, consensus-based, peer-reviewed assessments and reports of the IPCC, 

CCSP, and the National Academy of Sciences. Some commenters (9568, 9633) provided additional 

supportive references, citing Dr. James Hansen, Lord Nicholas Stern, Rajendra Pachauri, James Lovelock, 

and Stephen Hawking. One commenter (9749) referenced a report from the New Jersey Board of Public 

Utilities on climate and energy detailing the impacts of climate change on the quality of life in New 

Jersey. 

16 
Response (1-16): 

We agree that reliance on the peer-reviewed assessment literature is appropriate and reasonable. We have 

closely reviewed and considered the additional studies submitted by the commenter and we find that these 

materials are consistent with the information summarized in the TSD. For example, the New Jersey report 

states that “Not only does climate change threaten New Jersey’s shoreline and ecology, but the 

socioeconomic impacts of global warming stand to be profound and costly.”

Comment (1-17): 

Several commenters (1005.1, 3303, 3330.1, 3427.1, 3446.3, and 3567.1) argue that many of IPCC’s 

conclusions are distorted, misleading, or incorrect. A number of commenters (0487, 1927, 3013, 3219.1, 

3303, 3567.1, 3707.1, 3764.1, and 4509) state that IPCC reports are based on poor-quality science. 

Response (1-17): 

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 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. 

We note that this response addresses the broad assertion made by commenters with regard to IPCC’s 

conclusions being distorted, misleading, or incorrect. Several of these commenters also provided specific 

reasons for why these conclusions are claimed to be distorted, misleading, or incorrect (e.g., due to 

inappropriate review processes) and we respond to these specific comments in the relevant volumes of 

this Response to Comments document. 

As a general matter, we disagree that the IPCC’s conclusions are distorted, misleading, or incorrect or that 

the IPCC relies on poor-quality science. As thoroughly discussed in our response to comment 1-14, the 

IPCC process for preparation and review of its reports demonstrate a formal and sustained commitment to 

transparency and rigor in report development, review, and acceptance and approval. The assessment 

reports we used in developing the TSD represent the best available science and supporting studies 

conducted in accordance with sound and objective scientific practices, are peer reviewed, and adhere to 

standards of quality based on objectivity, utility, and integrity. 

Comment (1-18): 

Several commenters (2679.1, 2972.1, 3136.1, 3323.1, 3327.1, 3330.1, 3347.4, 3394.1, 3794.1, 4003, 

4041.1, 4932.1, 5158, and 11046) argue that the IPCC reports are inappropriate for use in the 

endangerment finding because the underlying studies are out of date and that major scientific findings 

have appeared since IPCC (2007) that have changed the science community's understanding of what is 

presented in that report. 

Response (1-18): 

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 process. 

As part of this final Action, EPA updated the TSD to reflect new assessment reports published since 

release of the Proposed Findings and the TSD’s April 2009 version. In particular, we have revised the 

TSD to incorporate the findings of the latest assessment (released June 16, 2009) of the USGCRP. This 

17 
new study does not differ markedly from the fundamental conclusions of the IPCC. In fact, this most 

recent USGCRP assessment report integrates newer literature and builds on the key findings from the 

IPCC, USGCRP, CCSP, and NRC assessments to reach similar, and in some cases, stronger conclusions. 

In addition, the TSD incorporates up-to-date observational data for a number of key climate variables 

from the National Oceanic and Atmospheric Administration (NOAA), and the most up-to-date emissions 

data from EPA’s annual Inventory of U.S. Greenhouse Gas Emissions and Sinks, published in April 2009. 

We do not agree that it is inappropriate for the Administrator to use the IPCC assessment reports as part 

of the foundation for the Administrator’s endangerment determination. The assessment reports discussed 

in the TSD do reflect the state of science on climate change and are not out of date. 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. 

EPA’s responses to comments and literature submitted on specific climate science issues in the TSD are 

provided in the appropriate Response to Comment volumes. These responses indicate where new 

scientific information (from either new assessment reports or individual studies) reinforce, refine, or 

correct specific issues. EPA has addressed all significant scientific findings identified and submitted by 

commenters that have appeared since the IPCC (2007). 

Based on our review of the studies submitted during the public comment process as well as additional 

peer-reviewed literature published since IPCC’s Fourth Assessment Report, we find that IPCC’s 

conclusions are still accurate representations of the scientific community’s understanding of the science. 

Much of the more recent literature reaffirms IPCC’s conclusions, and even strengthens the confidence in 

key issues. 

Comment (1-19): 

Several commenters (3187.5, 3440.1, 4288, 9636, 9970, 11288, 11315, and 11409) argue that IPCC 

reports, including the Summary for Policymakers (SPM), are not appropriate resources for the 

endangerment finding because IPCC tasks government politicians with creating the documents instead of 

climate scientists. 

Response (1-19): 

We refer the commenters to previous responses to comments in this section regarding IPCC’s report 

development process. 

EPA disagrees with this comment for several reasons. First, the IPCC has clear procedures in place for the 

preparation of the SPM, which state that: “Summary sections of Reports approved by the Working 

Groups and accepted by the Panel will principally be the Summaries for Policymakers, prepared by the 

respective Working Groups of their full scientific, technical and socio-economic assessments, and 

Summaries for Policymakers of Special Reports prepared by the Working Groups” (IPCC, 1999). These 

procedures require the SPM to be drafted by teams of authors from the various underlying IPCC chapters, 

and the commenter has provided no information that demonstrates that “government politicians” were 

involved in the drafting. 

Second, the IPCC procedures build in processes to ensure that the findings of the SPM are consistent with 

the underlying IPCC reports: “Approval of the Summary for Policymakers at the Session of the Working 

Group, signifies that it is consistent with the factual material contained in the full scientific, technical and 

socioeconomic assessment or Special Report accepted by the Working Group. Coordinating lead authors 

may be asked to provide technical assistance in ensuring that consistency has been achieved” (IPCC, 

18 
1999). These procedures avoid the apparent concern of the commenter that an SPM could be inconsistent 

with the findings of the body of an IPCC report. 

Third, in developing the TSD as the scientific basis for the Administrator’s endangerment analysis, EPA 

relied predominantly on the full reports of IPCC (2007a, 2007e), not on the SPMs. Findings from the 

SPMs were only used to provide overarching discussions of climate science and impacts throughout the 

TSD Sections. 

Fourth, IPCC procedures and principles (see our response to comment 1-14 and Appendix A) demonstrate 

that in making decisions and approving, adopting, and accepting reports, the Panel, its Working Groups 

and any Task Forces shall use all best endeavors to reach consensus. In those cases where consensus is 

not reached, IPCC procedures require that the differing views shall be explained and, upon request, 

recorded. These procedures also specify that differing views on matters of a scientific, technical, or socioeconomic nature shall, as appropriate in the context, be represented in the scientific, technical, or socioeconomic document concerned. We note that neither SPM for IPCC (2007a) or IPCC (2007e) indicate 

that consensus was not reached. 

Any statement from an IPCC SPM used within the TSD is fully supported by the underlying, full report 

of the IPCC; all of the material taken from SPM Sections of these reports is supported by information in 

the underlying chapters. Commenters also have not identified any such statement that is inconsistent with 

this. 

Comment (1-20): 

Several commenters (1961, 3053, 3707.1, 3722, 3722.9, 3187.5, 7029, and 10196) argue that the authors 

involved in developing and reviewing IPCC (2007) all share the same views regarding climate change 

science, and that alternative perspectives were not incorporated into the process. These commenters also 

state that the IPCC authors commonly collaborate on research, and therefore were not capable of 

objectively reviewing and editing the content of IPCC (2007). A commenter (3187.5) specifically 

mentioned that IPCC’s authors on the climate modeling chapters do not represent a diversity of 

perspectives, as many of them work at the same research institutes and/or collaborate with each other. 

Response (1-20): 

We refer the commenters to previous responses to comments in this section (1-14, 1-15, 1-17, 1-18, 1-19) 

regarding IPCC’s report development process. 

EPA has carefully reviewed the IPCC procedures and does not agree with this comment. For an overview 

of the IPCC procedures, please see the Introduction of the TSD. As noted previously, Section 1(b) and 

Box 1.1 of the TSD provide a general description of the IPCC’s procedures. Both within the United States 

and within the IPCC, the objective was to ensure that the authors represented a range of perspectives and 

views. We note that the majority of these comments provide no specific evidence for their general 

assertion. Only one commenter (3187.5) provided a specific argument—a critique of the range of 

perspectives among the authors on Chapter 9 (“Understanding and Attributing Climate Change”) of WGI 

(IPCC, 2007a). We acknowledge that some of the 53 Chapter 9 authors are associated with the same 

research institutes; however, we find that the majority of them do not frequently collaborate on research. 

In fact, many of the research institutes, such as National Center for Atmospheric Research and the Hadley 

Center, work on their own climate modeling studies independently of other programs. Further, we find 

that the authors from Chapter 9 come from 31 different organizations and from over 15 different 

countries. In a field as small and technical as climate modeling, we conclude that representation from 31 

organizations sufficiently provides a range of perspectives. Even the commenter acknowledges this in 

their statement that “53 authors of chapter 9 came from just 31 organizations.” 

19 
The commenters also claim that the IPCC authors commonly collaborate on research and therefore are not 

objective. This claim is not supported by the evidence. Each IPCC report is developed by a team of 

authors, broken down into independent groups focusing on specific chapters, under the leadership of the 

Working Group Chairs and Convening Lead Authors. Please see the excerpt from IPCC’s Procedures 

(IPCC, 1999) at the end of this comment, which discusses the tasks and responsibilities for lead authors, 

coordinating lead authors, contributing authors, expert reviewers, and government reviewers. In addition 

to what is stated in this excerpt, the Procedures (IPCC, 1999) state that: 

Coordinating Lead Authors and Lead Authors are selected by the relevant Working 

Group/Task Force Bureau, under general guidance and review provided by the Session of 

the Working Group....The composition of the group of Coordinating Lead Authors and 

Lead Authors for a section or chapter of a Report shall reflect the need to aim for a range 

of views, expertise and geographical representation (ensuring appropriate representation 

of experts from developing and developed countries and countries with economies in 

transition). There should be at least one and normally two or more from developing 

countries. 

More than 500 authors and 2,000 reviewers (representing over 100 nations) were involved with 

developing IPCC (2007), and they offered a diversity of perspectives related to climate change science 

both during the drafting of the reports and during multiple comment opportunities. We find that the level 

of collaboration amongst the hundreds of authors is low and that the examples of collaborative efforts 

(e.g., co-authorship of studies) provided by commenters are isolated cases—especially when considering 

the large number of available studies upon which the assessment reports rely and the hundreds of authors 

who developed them. Further, there is no evidence provided that supports the claim that collaboration 

among a small number of the authors prevented the incorporation of a range of perspectives and 

alternative views or biased the conclusions. 

In addition, Review Editors oversee the integrity of the response to comment processes for all IPCC 

reports. IPCC’s guidelines for report development (IPCC, 1999) state that: 

Three principles governing the review should be borne in mind. First, the best possible 

scientific and technical advice should be included so that the IPCC Reports represent the 

latest scientific, technical and socio-economic findings and are as comprehensive as 

possible. Secondly, a wide circulation process, ensuring representation of independent 

experts (i.e. experts not involved in the preparation of that particular chapter) from 

developing and developed countries and countries with economies in transition should 

aim to involve as many experts as possible in the IPCC process. Thirdly, the review 

process should be objective, open and transparent. 

To help ensure that Reports provide a balanced and complete assessment of current 

information, each Working Group/Task Force Bureau should normally select two Review 

Editors per chapter (including the executive summaries) and per technical summary of 

each Report. 

Review Editors should normally consist of a member of the Working Group/Task Force 

Bureau, and an independent expert based on the lists provided by governments and 

participating organizations. Review Editors should not be involved in the preparation or 

review of material for which they are an editor. In selecting Review Editors, the Bureau 

should select from developed and developing countries and from countries with 

20 
economies in transition, and should aim for a balanced representation of scientific, 

technical, and socio-economic views. 

We do not find merit in the argument that the IPCC procedures or the IPCC authors lack objectivity or 

integrity. Please see the relevant Response to Comment volumes for our responses to any specific 

technical comments provided on the IPCC findings or processes. 

The following is an excerpt from IPCC’s Procedures (IPCC, 1999) describing the tasks and 

responsibilities for lead authors, coordinating lead authors, contributing authors, expert reviewers, and 

government reviewers. Appendix A of this volume contains IPCC’s Procedures (IPCC, 1999) in its 

entirety. 

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 

21 
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. 

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 

22 
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 

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. 

6. GOVERNMENT FOCAL POINTS 

Function: 

To prepare and update the list of national experts as required to help implement the IPCC 

work program, and to arrange the provision of integrated comments on the accuracy and 

completeness of the scientific and/or technical content and the overall scientific and/or 

technical balance of the drafts. 

Comment: 

Government review will typically be carried out within and between a number of 

Departments and Ministries. 

For administrative convenience, each government and participating organization should 

designate one Focal Point for all IPCC activities, provide full information on this Focal 

Point to the IPCC Secretariat and notify the Secretariat of any changes in this 

information. The Focal Point should liaise with the IPCC Secretariat regarding the 

logistics of the review process(es). Of particular importance is the full exchange of 

information. 

Comment (1-21): 

Several commenters (0800.1, 3440.1, 4528, 4666, 4670, and 4766) argue that IPCC relies too heavily on 

models and simulation tools in making conclusions and that climate models are inappropriate tools for an 

endangerment analysis. 

Response (1-21): 

EPA received many specific comments on the use of models and simulation tools in the context of the 

TSD and as support for the endangerment analysis. Please see the relevant Response to Comment 

23 
volumes for our responses to these specific comments, particularly Volume 4, which focuses specifically 

on climate models and highlights other lines of evidence relevant to particular conclusions. 

As a general matter, we find that IPCC’s reliance on models to evaluate the key elements of climate 

change science is appropriate and that these tools help scientists better understand the many climatic, 

geological, chemical, and biological systems involved with climate change. Furthermore, we find that the 

IPCC carefully documents and discusses uncertainties, assumptions, and limitations of the models used, 

and we have incorporated this information into the TSD. The climate models and other models used in the 

IPCC report meet the standards of the best available science available: they have been validated and 

compared against theory, observation, and other models. The models are routinely used in scientific 

practice throughout the country and the world. The TSD appropriately represents both the strengths and 

limitations of the models, as determined by the major assessment reports. 

In addition, it is important to recognize that the most important conclusions regarding climate science and 

impacts are based on numerous independent sources of information, including observations of the 

changing GHG composition of the atmosphere, observed changes in the climate system, and observed 

changes to physical and biological systems. 

Comment (1-22): 

Several commenters (3394.1, 3440.1, 3722, and 4509) specifically state that in developing the TSD, EPA 

did not give proper consideration to the numerous uncertainties in IPCC's findings. 

Response (1-22): 

Please see Section 1.2 of this document for responses to these comments and for a general discussion of 

uncertainty. In addition, please see the relevant Response to Comment volumes for our responses on the 

treatment of uncertainty regarding specific issues in the TSD. 

Comment (1-23): 

Several commenters (3394.1, 3705.1, 3747.1, and 3482.1) argue that IPCC assessments are devoted 

primarily to global effects and global emissions and are therefore inappropriate for describing the 

observed and projected impacts of climate change in the United States necessary for an endangerment 

finding. 

Response (1-23): 

We do not agree that IPCC reports are inappropriate for an assessment of climate impacts in the United 

States. As explained in the TSD, the IPCC (2007b) includes a chapter on North America, which focuses 

on impacts, adaptation and vulnerability in the United States and Canada. We find that the North America 

chapter draws from many individual studies on the United States and provides United States–specific 

findings, many of which are included in the TSD. We also note that IPCC (2007) contains a chapter on 

small islands with specific findings for U.S. islands and territories, along with a chapter on polar regions 

which includes Alaska-specific discussions. Where the TSD references IPCC conclusions for global or 

regional areas that include the United States and other areas, we ensured that the conclusions were applied 

appropriately and accurately. Perhaps more importantly, we ensured that the TSD did not summarize 

conclusions from the assessment literature which did not apply to or were not appropriate for the United 

States. We received comments of this nature regarding specific climate science issues and our responses 

can be seen in the relevant volumes of this Response to Comments document. Our approach is entirely 

reasonable and consistent with how IPCC intended the conclusions to be used. 

24 
Finally, we note that the TSD summarizes important findings and conclusions from reports of the 

USGCRP and CCSP, which focus almost exclusively on the United States. In particular, we updated the 

TSD to reflect the findings of the June 2009 USGCRP assessment report, by adding additional 

information to the sectoral chapters in Section IV of the TSD and a new section (15) on U.S. regional 

climate change impacts. 

Please see other relevant Response to Comment volumes for our response to specific comments related to 

the TSD’s discussion of particular U.S. climate impacts, and Volume 9 for our response to comments on 

the global and domestic scope of the endangerment finding. 

Comment (1-24): 

Several commenters (3287.1, 3291.1, 3379.1, 3394.1, 3407, 3482.1, and 3705.1) state that EPA’s 

adoption of the IPCC’s regional analysis of North American impacts, including projections for changes in 

temperature, precipitation, and sea level rise, cannot substitute for a U.S.–specific analysis because the 

IPCC’s assessment failed to distinguish adequately between U.S. and Canadian effects. 

Response (1-24): 

Please refer to the previous comment for our response regarding the applicability of the IPCC discussion 

of climate impacts to the United States. 

1.1.2 Specific Comments on EPA’s Use of CCSP and USGCRP Reports 

Comment (1-25): 

A commenter (3765.1) encourages EPA to refer to the findings of the USGCRP's assessment report 

Global Climate Change Impacts in the United States.

Response (1-25): 

The TSD has been revised to cite the final version of this report (Karl et al., 2009). 

We find that this report and the other scientific assessments of the IPCC, CCSP, and NRC represent the 

best reference materials for determining the general state of knowledge on the scientific and technical 

issues before the agency in informing an endangerment decision. The Guidelines for Producing CCSP 

Synthesis and Assessment Products (CCSP, 2004) state that: 

Independent scientific judgment should serve as the guiding force in preparing the products so 

they are credible. 

Scientists, users, and other stakeholders should jointly determine the scope of the products so the 

topics covered are well defined and the information provided is relevant to the needs expressed. 

The process of preparing the products should be open at every step so the products have 

legitimacy (i.e., are perceived to have been prepared fairly). 

The process used by USGCRP/CCSP in developing their assessment reports is robust, transparent, and 

objective. We refer the commenters to Appendix B of this volume, which contains the following CCSP 

documents: 1) Guidelines for Producing CCSP Synthesis and Assessment Products (2004), 2) a CCSP 

memo on Clarification of Review and Clearance Process for CCSP Synthesis and Assessment Products, 

(2007), and 3) Guidance to Agency Leads Regarding the Preparation of CCSP Synthesis and Assessment 

25 
Products (2006). Regarding the steps necessary in developing the assessment reports, CCSP (2004) 

describes the following procedures: 

Planning the Process and Preparing a Prospectus 

1. The lead agency(ies) solicit input from users and other stakeholders, plan preparation 

of the product, and summarize the proposed process in a draft prospectus. The draft 

prospectus will address the topics listed in the subsequent section of this document. 

2. The CCSP Interagency Committee reviews and approves the draft prospectus for 

public comment. 

3. Expert reviewers and stakeholders review the draft prospectus. The prospectus 

comment period will last at least 30 days. The draft prospectus comment period will be 

announced in a Federal Register Notice (FRN) and posted on the CCSP web site. 

4. The lead agency(ies) revise the draft prospectus and finalize author recommendations, 

taking into consideration the comments received. 

5. The CCSP Interagency Committee approves the revised prospectus and the lead 

agency(ies) notify the lead authors. 

6. The CCSP Office posts the draft prospectus comments and the final prospectus on the 

CCSP web site. 

Additional Stakeholder Interactions, if Needed 

7. Lead authors may solicit additional input from users and other stakeholders to assist in 

the development of the product. The process for soliciting this additional input will be 

open and described in the prospectus. Approaches include workshops, user surveys, 

telephone and email conferences, and other mechanisms. The processes used will reflect 

the expected end use of the product. The CCSP Strategic Plan identifies three end uses 

for CCSP synthesis and assessment products: 1) informing the evolution of the research 

agenda; 2) supporting adaptive management and planning; and 3) supporting policy 

formulation. The products with end uses primarily oriented toward the second and third 

categories are expected to require significant additional input from users to develop a 

clear understanding of information needs, timing of decisions, consideration of how 

uncertainty affects decision making, and other issues. The results from additional 

stakeholder interactions will be publicly available in summary or more extensive forms 

through publication on the CCSP web site. 

Drafting/Reviewing the Products 

8. Lead authors prepare the first draft, including a technical section and a summary for 

interested non-specialists. 

9. The lead agency(ies) organize and facilitate an expert peer review of the first draft 

according to process described in the prospectus. The expert peer review will precede the 

public comment period to ensure that the products are shaped by scientific 

considerations. The expert peer review process may range from that used in a scientific 

journal to a formal review panel convened by the lead agency or recognized external 

groups such as the National Research Council. Participants must be qualified 

scientific/technical experts, as demonstrated by their record of scholarly publication and 

other accomplishments. Employees of the lead agency(ies), lead authors, and other 

26 
contributors to the product may not serve as expert reviewers for that product. The 

prospectus will describe the process for selecting expert reviewers and the expected dates 

of the review. If the expert peer review is open to all qualified experts, notice will be 

disseminated on the CCSP web site and through relevant scientific publications, web 

sites, and other means. All comments submitted during the expert peer review will be 

publicly available without attribution to the reviewer unless reviewers agree in advance to 

posting with specific attribution. 

10. Lead authors prepare the second draft of the product, taking into consideration the 

expert peer review comments. The scientific judgment of the lead authors will determine 

responses to the comments. The authors will acknowledge significant contributions made 

by expert reviewers, as applicable. 

11. The lead agency(ies) post the second draft of the product for public comment for not 

less than 45 days. Any stakeholders (plus experts who participated in the expert peer 

review process) may participate in the public comment period for the second draft. This 

includes governmental and non-governmental entities. The prospectus will include the 

expected dates of the public comment period. Notice of the public comment period will 

be disseminated on the CCSP web site, in the Federal Register, and through other 

publications, web sites, and means as appropriate to the product, to encourage wide 

public participation in the review. All comments will be publicly available. 

12. The lead authors will prepare a third draft of the product, taking into consideration the 

comments submitted during the public comment period. The scientific judgment of the 

lead authors will determine responses to the comments. 

Approving, Producing, and Releasing the Products 

13. Lead agency(ies) submit the third draft of the product and a compilation of comments 

received to the CCSP Interagency Committee. 

14. If the CCSP Interagency Committee review determines that no further action is 

needed and that the product has been prepared in conformance with these guidelines and 

the Data Quality Act (including ensuring objectivity, utility, and integrity as defined in 67 

FR 8452), they will submit the product to NSTC for approval. If the CCSP Interagency 

Committee determines that further revision is necessary, their comments will be sent to 

the lead agency(ies) for consideration and resolution by lead authors. 

15. If needed, NRC can be asked to provide additional scientific analysis to bound 

scientific uncertainty associated with specific issues. 

16. Once the CCSP Interagency Committee has determined that the synthesis and 

assessment report has been prepared in conformance with these guidelines and the Data 

Quality Act, the Committee will submit it to NSTC for final review and approval. 

Approval will require the concurrence of all members of the Committee on Environment 

and Natural Resources. Comments generated during the NSTC review will be addressed 

by the CCSP Interagency Committee. 

17. Once NSTC approval has been obtained and the product is finalized, the lead 

agency(ies) will produce and release the completed product using a standard format for 

all CCSP synthesis and assessment products. The final product and the comments 

27 
received during the expert review and the public comment period will be posted, without 

attribution (unless specific reviewers agree to attribution), on the CCSP web site. 

 

18. The product will be widely disseminated through the CCSP web site and other 

mechanisms. 

The USGCRP/CCSP Guidelines (CCSP, 2004) lay out specific procedures regarding the roles and 

responsibilities of the lead agency or agencies, lead and contributing authors, interagency working groups, 

expert reviewers, stakeholders, NRC, and the National Science and Technology Council. These 

procedures were closely adhered to in developing the assessment reports and we note that no commenters 

submitted evidence to the contrary. The implementation of these guidelines ensured that the reports were 

being written using the best available science and objectively peer-reviewed. The Guidelines state: 

 

Lead Agency(ies)/Department(s) 

One or more designated CCSP agency(ies) or department(s) will take the lead in 

producing each product. The lead agency(ies) will be responsible for developing an open 

and transparent process for soliciting user input, author nomination and selection, expert 

peer review and public comment, and production/release of the products, as described in 

these guidelines. To ensure that the products incorporate as much expertise as possible, 

the lead agency(ies) will be open to the participation of other individuals or entities with 

relevant expertise and information. The entities can include other government units 

(Federal or non-Federal), Interagency Working Groups of the CCSP or other Federal 

programs, international organizations and government units, non-governmental 

organizations (NGOs), and other groups. 

Lead and Contributing Authors 

Lead and contributing authors of the synthesis and assessment products are scientists or 

individuals with recognized technical expertise appropriate to a product. Lead and 

contributing authors may be citizens of any country and be drawn from within or outside 

the Federal government (e.g., universities or other public or private sector organizations). 

These individuals shall be acknowledged experts, known through their publication record 

and relevant accomplishments and contributions to their field. Lead authors are 

responsible for the content of the synthesis and assessment products that are submitted to 

the CCSP Interagency Committee for review. 

Interagency Working Groups 

The CCSP Interagency Committee coordinates implementation of its activities in support 

of the Strategic Plan through Interagency Working Groups (IWGs) of program specialists 

of its participating departments and agencies, as described in Chapter 16, “Program 

Management and Review,” of the CCSP Strategic Plan. IWGs will contribute 

significantly to the preparation of the synthesis and assessment products because of their 

expertise in areas related to the products. IWGs may serve as a means for the lead 

agency(ies) to coordinate preparation of the products with supporting agencies. They may 

contribute to planning/preparing the prospectuses, scoping, drafting, reviewing, 

publishing, or disseminating the final product. 

Expert Reviewers 

Expert reviewers are scientists or individuals with other special expertise appropriate to a 

product. The expert reviewers will be selected by the lead agency(ies)/departments. As is 

the case for lead and contributing authors, reviewers may be citizens of any country and 

be drawn from within or outside the Federal government (e.g., universities or other public 

28 
or private sector organizations). These individuals shall be known through their 

publications and other forms of recognition of their expertise. Expert reviewers will focus 

on the scientific/technical content of the draft. Employees of the lead agency(ies), lead 

authors, and other contributors to the product may not serve as expert reviewers for that 

product. The expert reviewers will be designated through a process described in the 

prospectus. 

Stakeholders 

Stakeholders are defined as they are in Chapter 11 of the CCSP Strategic Plan—that is, 

“Stakeholders are individuals or groups whose interests (financial, cultural, value-based, 

or other) are affected by climate variability, climate change, or options for adapting to or 

mitigating these phenomena.” Stakeholders participate during the scoping process by 

providing information that helps define the audience and potential uses of a product. In 

addition, stakeholders provide comments on the prospectus, and on the product during the 

public comment period. These comments are expected to focus on how well the product 

serves its intended purpose or use. 

National Research Council 

The National Academy of Sciences / National Research Council (NRC) will provide 

advice on an as-needed basis to the lead agency(ies). In the event that issues are identified 

that require further clarification, the NRC may be asked to provide additional scientific 

analyses to help bound the uncertainty associated with these issues. 

National Science and Technology Council 

The National Science and Technology Council (NSTC) will be responsible for final 

review and approval of the synthesis and assessment products. Products not cleared by 

NSTC cannot be released as disseminations of the Federal government. Consistent with 

NSTC procedures, approvals will require written concurrence from all members of the 

NSTC’s Committee on Environment and Natural Resources (CENR). All comments 

generated through the NSTC review will be addressed by the CCSP Interagency 

Committee. The CENR membership includes senior officials representing the Executive 

Office of the President and the 15 federal agencies with significant responsibilities for 

environment and natural resources programs. 

The USGCRP/CCSP Guidelines (CCSP, 2004) also lay out specific procedures regarding the types of 

scientific materials to be used in the development of the assessment reports. This ensures that the reports 

are credible, robust, and representative of the best available science. After reviewing the final USGCRP 

and CCSP products, we find that these guidelines were consistently implemented. The Guidelines state: 

Authors will use the published, peer-reviewed scientific literature in drafting the 

products. In the rare case that any materials used in preparing a product are not already 

published in the peer-reviewed literature, the lead agency(ies) must get approval from the 

CCSP Interagency Committee and these materials must be made available by the lead 

agency(ies) and/or CCSP Office. The use of any such non-peer-reviewed materials may 

be questioned by reviewers during the expert review or public comment period. Authors 

should seek to publish any materials used in preparing drafts of the products. 

To ensure transparency in the assessment report development process, USGCRP/CCSP provided the 

public with access to a series of documents, including invitations for public comment periods on the 

prospectus’ and preliminary drafts, compilations of comments received from the public and experts, and 

revised versions of the reports. For each assessment report, the following products were posted on the 

29 
appropriate synthesis and assessment product (SAP) Web site, although we note that additional SAPspecific products were posted for many of the reports: 

Invitation for public comment on draft prospectus 

Draft prospectus 

Public comments on draft prospectus 

Final prospectus 

Peer review plan (if not part of the prospectus) 

Expert review comments on first draft report and authors’ responses to them 

Invitation for public comment on second draft report 

Second draft report 

Public comments on second draft report and authors’ responses to them 

Third draft report 

Final report 

Finally, to ensure that each assessment report complied with the Information Quality Act (IQA) and was 

fully responsive to all comments received from the public and expert review, the USGCRP/CCSP 

Guidelines (CCSP, 2004) state that: 

When the lead agency transmits the product for final clearance, they should include a 

memorandum briefly indicating that “the product was prepared in compliance with 

CCSP’s Guidelines for Producing Synthesis and Assessment Products, the Information 

Quality Act (Section 515) and [LEAD AGENCY’S] corresponding IQA guidelines; and 

the Federal Advisory Committee Act [when applicable].” This transmittal should include 

the authors’ responses to the peer reviewer comments, as required by OMB’s Information 

Quality Bulletin for Peer Review, as well as descriptions of how the authors addressed 

the public comments and lead agency’s review comments. 

Comment (1-26): 

A commenter (4036.5) states that EPA's use of CCSP 4.6 (Gamble, 2008) and the IPCC (2007) Working 

Group II chapter on human health impacts represent the consensus opinion of the world’s leading 

scientists studying health impacts of climate change. 

Response (1-26): 

CCSP 4.6 and the IPCC chapter on human health impacts are robust sources of information to serve as 

primary sources for the discussion of health impacts. See Volume 5 of the Response to Comments for 

responses to specific comments on human health and air quality. 

Comment (1-27): 

Two commenters (3446.2 and 3136.1) note numerous errors and contentious statements in the public draft 

of USGCRP's assessment report Global Climate Change Impacts in the United States and cautioned that 

this document was not based on best available science. 

Response (1-27): 

EPA did not cite the draft USGCRP report in the version of the TSD released in April 2009 with the 

Proposed Findings. However, we have revised the TSD to incorporate the conclusions of the final 

USGCRP report, which was released in June 2009 (Karl et al., 2009). Regarding the quality and accuracy 

of the public review draft, we note that USGCRP substantially revised the report following the two 

30 
separate rounds of public comment and expert review. Commenters can review how USGCRP responded 

to the comments received at (http://www.climatescience.gov/Library/sap/usp/default.php). 

Please see other relevant Response to Comment volumes for our response to specific comments on the 

USGCRP that relate to the TSD’s discussion of particular issues. See our response to other comments 

summarized in this section of this volume for a description of our rationale as to why the USGCRP report 

represents the best available scientific information and, in its final form, meets the TSD's established 

reference criteria. 

Comment (1-28): 

As evidence why the EPA should not rely on CCSP synthesis reports, a commenter (3136.1) submitted to 

EPA their comments on the USGCRP’s Global Climate Change Impacts on the United States, originally 

submitted during the public comment period for that report. While nearly all of the comments raised by 

commenter 3136.1 address specific issues regarding the climate science and impacts information within 

the USGCRP report, one overarching issue raised in the comments was that the USGCRP authors made 

little effort to consider or include any dissenting opinion to their declarative statements. 

Response (1-28): 

EPA has reviewed the comments submitted, and our responses are provided in the relevant Response to 

Comment volumes related to the TSD’s discussion of particular climate science and impacts issues. We 

also refer commenters to previous responses to comments in this section regarding the USGCRP/CCSP 

report development process. We also note that Box 1.1 of the TSD provides a description of the peerreview, publication, and approval processes employed by CCSP and USGCRP in developing their 

assessment reports. 

The overarching comment that USGCRP made little effort to consider or include dissenting opinions is 

inconsistent with the process used by USGCRP in developing the report. We note that the USGCRP 

report and the previously developed CCSP reports have assessed numerous individual, peer-reviewed 

studies in order to draw general conclusions about the state of the science. This process involves weighing 

the quality of different individual studies (including dissenting opinions), reconciling studies with 

divergent conclusions, and acknowledging divergent conclusions (or a dearth of findings for a given area) 

to highlight key scientific uncertainties and gaps in knowledge. Further, CCSP and USGCRP provided 

multiple opportunities for input through several public comment periods, which were held for each SAP 

and the synthesis report. These comment periods allowed the public to submit dissenting opinions and 

studies that were considered by CCSP prior to releasing the final reports. Responses to the comments 

received during the two rounds of public review and two rounds of expert peer-review on the draft 

synthesis report can be viewed at http://www.climatescience.gov/Library/sap/usp/default.php. Finally, we 

note that the USGCRP/CCSP memorandum on Clarification of Review and Clearance Process for CCSP 

Synthesis and Assessment Products states that final clearance procedures employed by CCSP ensure that 

the officials with legal responsibility for the assessment reports have reviewed and approved them, with 

particular consideration that “the expert review and public comments were adequately addressed by the 

authors.” 

Comment (1-29): 

A commenter (2684.1) argues that the CCSP reports cited by EPA are not used as references in peerreview scientific papers, and that without technical merit, these papers are of little scientific value. 

Response (1-29): 

31 
We disagree with the commenter that the CCSP reports are not being used as references in reports and 

papers. We analyzed the citation rate of CCSP reports in recent published, peer-reviewed studies and 

found that these assessments are being referenced frequently, especially since these reports were only 

recently released (most in 2008 and 2009). For example, a CCSP report on temperature trends in the 

lower atmosphere (CCSP, 2006) has been cited in over 50 papers published in peer-reviewed science 

journals. For the reasons provided in the Findings, Section III.A., and our response to comments in the 

section, we find that the CCSP reports represent scientifically robust and credible sources of information 

on climate science and impacts. 

Comment (1-30): 

A commenter (3411.1) argues that there are additional studies on the issue of air quality impacts that the 

Agency does not address in the proposed endangerment finding or the TSD. The commenter requests an 

on-the-record proceeding at which all the available government-funded studies can be assessed. 

Response (1-30):

See previous responses in this section for our response regarding the approach taken to review and reflect 

additional studies and new literature in the endangerment analysis. See Response to Comment Volume 5 

for our response to specific comments on the issue of air quality impacts, which includes responses to 

additional studies submitted through the public comment process. See Section 1.C.1(e) of the Findings for 

our response to comments on the subject of an “on-the-record proceeding” under the Administrative 

Procedures Act. 

1.2 Level of Scientific Certainty 

Comment (1-31): 

A commenter (2692) indicates that EPA’s discussion of the health impacts of climate change contains 

ambiguous terms such as “difficult to ascertain,” “expected,” “could,” “potential,” “likely,” “can,” “very 

likely,” “likely to,” “may,” and “projected.” Yet the EPA draws a “compelling and indeed, 

overwhelming” conclusion from such ambiguity. The commenter argues that how EPA arrives at this 

conclusion is puzzling. 

Response (1-31):

In response to this comment, EPA has reviewed both the use of these terms in the TSD and Findings, as 

well as the explanation of our approach in the TSD. We agree with the commenter that clear and careful 

communication of uncertainty is important, and this is, in fact, a strength of the TSD. Box 1.2 of the TSD 

summarizes the approach and lexicon developed by the IPCC, USGCRP, and CCSP for the consistent 

communication of uncertainty and likelihood. As the TSD makes clear, the IPCC, USGCRP, and CCSP 

have established guidelines for the use of these types of terms precisely to minimize the ambiguity and 

misinterpretation that can occur when their meaning is not defined. In summarizing the existing and fully 

vetted literature, we adopted this existing approach. 

Many of the terms identified by the commenter are defined in Box 1.2, to aid readers in better 

understanding the implications of various statements throughout the TSD. For example, “likelihood” 

refers to a probabilistic assessment of some well-defined outcome having occurred or occurring in the 

future, and may be based on quantitative analysis or an elicitation of expert views. Terms used to describe 

likelihood of certain outcomes include “virtually certain,” “very likely,” “likely,” “about as likely as not,” 

“unlikely,” “very unlikely,” and “exceptionally unlikely”; as summarized in the Box 1.2, each term has an 

associated probability of occurrence. The term “projected” is used to explain an outcome in the future 

32 
typically based on modeling analysis and are often accompanied by a term to communicate the outcome’s 

probability. Because the TSD summarizes the results of the major climate assessment reports, we 

concluded it was neither necessary nor appropriate for EPA to develop a new vernacular to convey 

likelihood and probability information. There are some phrases used in the TSD, such as “difficult to 

ascertain,” that indicate that available information is insufficient for experts to make an assessment or 

assign a probability. 

In response to this comment, we also revised Box 1.2 of the TSD to enumerate potential sources of 

uncertainty and add discussion about the importance of characterizing uncertainty. We also made 

revisions to more clearly describe how confidence levels were developed in IPCC (2007). 

See Section IV.B. of the Findings for a description of how the Administrator weighed the information 

contained in the TSD and broader record in making the endangerment determination, and her view of the 

weight of the evidence. 

Comment (1-32): 

Some commenters (e.g., 1927) state that policy and regulation should not be based on likelihood and that 

IPCC statements, for example, cannot be proven with certainty. A commenter (3397) argues that EPA did 

not provide sufficient guidance on the likelihood of occurrence of impacts. 

Response (1-32):

See our response to the previous comment regarding how EPA communicated information on uncertainty 

and likelihood in the TSD. See II.A.2.a. of the Findings for our response on the question of whether 

policy and regulation can be based on likelihood, and Section IV.B. of the Findings for our response to 

comments regarding how the Administrator weighed the information contained in the TSD and the 

broader record. 

To the extent possible, EPA indicates the likelihood of occurrence in its discussion of impacts. Box 1.2 in 

EPA’s TSD describes the communication of confidence and uncertainty for IPCC and USGCRP (or 

CCSP) assessments, which are its primary underlying references. When EPA cites these references, it 

retains their confidence and uncertainty language. 

Comment (1-33): 

A large number of commenters (e.g., 0463, 0727, 1927, 2253, 2750, 2898.1, 2923, 3080, 3347.1, 3384, 

3427.1, 3435.1, 3498.1, 3507.1, 3559.1, 3577.1, 3559.1, 3577.1, 3702.2, 3830.1, 4738, 4173ANPRref1, 

8978.1, A13, 10855, 10160, 11459) posit that the evidence for human-induced warming is weak or the 

consequences of global warming, even if human-induced, are too uncertain to make an endangerment 

finding. Many commenters note the evidence of harm is equivocal and/or doubt that possible 

current/future negative effects from warming outweigh benefits. Some commenters (4002, 3435.1) 

suggest that in light of the uncertainties enumerated by EPA and potential positive climate change effects, 

the endangerment finding appears to be more of a political than a scientific determination. 

Response (1-33):

The Administrator carefully evaluated the scientific evidence summarized in the TSD, which reflects the 

major conclusions of the assessment literature on issues pertinent to this finding. The public comments 

submitted on this action, including other scientific literature, were also reviewed and considered. On the 

basis of her review, the Administrator finds that the scientific information in totality provides compelling 

evidence of human-induced climate change. Section IV.B. of the Findings describes the Administrator’s 

33 
determination regarding the consequences of climate change and why they justify a finding of 

endangerment. For the reasons explained there, the Administrator rejects the view that the consequences 

are too uncertain to justify an endangerment finding. 

Many of the commenters who maintain there is too much uncertainty to support an endangerment finding 

raise specific scientific and technical concerns; our responses to these specific comments are provided in 

the other volumes of the Response to Comments document. 

At least one commenter incorrectly claims the decision is more a political than a scientific determination. 

Section II of the Findings (“the Legal Framework for this Action”) explains how Section 202(a) requires 

the Administrator to exercise her judgment and apply the evidence to the statutory endangerment criteria. 

As stated there, “[b]Because scientific knowledge is constantly evolving, the Administrator may be called 

upon to make decisions while recognizing the uncertainties and limitations of the data or information 

available, as risks to public health or welfare may involve the frontiers of scientific or medical 

knowledge. At the same time, the Administrator must exercise reasoned decision making, and avoid 

speculative inquiries.” That is what the Administrator has done, and the result is neither a political nor a 

scientific decision, but an exercise of judgment that is informed by and strongly grounded in the science 

and the law. 

Comment (1-34):

A number of commenters (0152, 0718, 0726, 0730, 2895, 3502.1ANPRref1, 4036.5, 5844, 6708, and 

9418) state EPA can and should act in the face of uncertainty, as the Agency has done in the past, to 

prevent threat to human health and the environment consonant with the bedrock foundation of the CAA, a 

law that is anchored in protective action. Some of these commenters also indicate it is wise for EPA to act 

in light of the number of scientists whose findings support EPA’s actions. 

Response (1-34): 

As discussed in Section II of the Findings, the Administrator is required to protect public health and 

welfare, but she is not asked to wait until harm has occurred. EPA must be ready to take regulatory action 

to prevent harm before it occurs. Section 202(a)(1) requires the Administrator to “anticipate” “danger” to 

public health or welfare. The Administrator is thus to consider both current and future risks. See above 

comment response regarding the Administrator consideration of uncertainty. 

Comment (1-35): 

A commenter (2895) recommends that EPA make policy based on probability rather than uncertainty. 

The commenter cautions that making policy based on uncertainty would require EPA to consider all 

future possibilities irrespective of their likelihood. It suggests EPA rely on the most likely scenarios in its 

decision-making. 

Response (1-35): 

The Administrator made her findings based on the totality of scientific evidence, some of which was 

assessed as being virtually certain or had been assigned high or very high probabilities in the assessment 

literature, while other evidence was less certain. The Administrator considered all of this evidence, and 

did not restrict herself to only the evidence of highest likelihood. She weighted and evaluated those 

scenarios, as well as scenarios of lesser probability, to evaluate the full range of risks and potential harms 

that climate change could lead to in the United States. See Section IV.B. of the Findings for her rationale 

in finding endangerment of both public health and welfare. 

34 
Comment (1-36): 

Several comments (2057, 3291.1, 3906) argue IPCC’s lexicon for communicating uncertainty is flawed. 

One comment argues that the probability assessments of IPCC reflect the judgment of the authors rather 

than empirical data, and that the IPCC probability assessments express greater certainty than the actual 

method supports. Specifically, it notes when presenting statistical information, IPCC uses a 90 percent 

confidence interval, not the 95 percent confidence interval that is standard scientific practice, making the 

results look more robust than they actually are. 

Response (1-36): 

IPCC’s application of uncertainty lexicon is primarily based on the results of probabilistic assessments 

and some are based on an elicitation of expert views rather than quantitative analysis. However, given the 

level of expertise of IPCC-nominated lead authors as well as the multi-stage review process, we find that 

the expert elicitation conducted by IPCC is legitimate. More information regarding the approach to 

addressing uncertainties in IPCC (2007) is available in the document Guidance Notes for Lead Authors of 

the IPCC Fourth Assessment Report on Addressing Uncertainties, which is located in Appendix A of this 

volume 

The assertion that IPCC strayed from scientific convention in its use of 90% confidence intervals is 

baseless. In statistical analysis, 5th and 95th percentiles are commonly used because they refer to a result 

two standard deviations from the mean in a normal distribution – in other words, they help show how 

much variation there is from the average or mean. The probabilistic assessments performed by IPCC are 

not statistical analyses but rather reflect expert elicitation and/or the results of quantitative analysis. These 

are two different processes. There is no rationale for the IPCC to adopt the statistical convention for 

describing a normal distribution to characterize uncertainty. 

Comment (1-37): 

A number of commenters (e.g., 0659, 1312, and 10855) note that scientists were offering warnings about 

global cooling in the 1970s (some cite examples), and therefore question the credibility of climate change 

science and the plausibility of projections. 

Response (1-37): 

Climate change statements and predictions made in the 1970s were not based on the current state of 

climate change science knowledge. Since the 1970s, marked improvements have been made in scientific 

understanding of climate change due to important theoretical discoveries, new and improved observing 

systems, and vastly superior computational and modeling resources. Furthermore, a recent study 

(Peterson et al., 2008) surveyed scientific papers published between 1965 and 1979 that projected future 

climate trends, and found that only 12% inclined toward future cooling, while most papers predicted 

future warming. The study concluded: “There was no scientific consensus in the 1970s that the Earth was 

headed into an imminent ice age. Indeed, the possibility of anthropogenic warming dominated the peerreviewed literature even then.” 

Comment (1-38): 

Many commenters (e.g., 0223, 0261, 0524, 0718, 0726, 1318.1, 3361.1, 3454.1, 3455.1, 3606.1, 3893, 

3940, 4136, 4171, 4247, 4841, 6055, 6227, 6465, 6525, 6599, 6622, 6936, 6937, 9298, 9520, 9642, 

10003, 10033, 11198, 11249, 11305) argue that the state of the science (i.e., breadth and depth) is strong 

enough to defend the Proposed Findings and that there exists “incontrovertible evidence...that carbon 

dioxide and other global warming pollution endangers public health and welfare.” 

35 
Response (1-38): 

We agree with the commenters that the state of the science is strong enough to support the finding.

Comment (1-39): 

Commenters (e.g. 3080, 10160) argue EPA should consider the option of waiting some period of time to 

make an endangerment determination because the scientific uncertainty is too great to make a 

determination at present. 

Response (1-39): 

The Administrator has determined the scientific information available now is sufficiently robust for 

making an endangerment finding. For more information on the Administrator’s rationale for making her 

finding, please refer to Section IV.B. of the Findings. 

Comment (1-40): 

Several commenters (3283.1, 4173ANPRref1) specifically reference the 2001 NRC report Climate 

Change Science: An Analysis of Some Key Questions (NRC, 2001a) to assert that the science is too 

uncertain for the Administrator to make a reasoned judgment on endangerment. They note that report 

stated, for example, that a causal linkage between the buildup of greenhouse gases in the atmosphere and 

the observed climate change during the 20th century cannot be unequivocally established (owing to the 

still uncertain natural variability inherent in the climate record and the uncertainties in the time histories 

of the various forcing agents and particularly aerosols) and that the health consequences of climate 

change are poorly understood. One commenter argues that since the 2001 NRC report, areas of concern 

noted by NRC like the importance of aerosols have become less well understood. The commenter 

concludes that EPA has not demonstrated the scientific information supporting the endangerment finding 

is adequate. 

Response (1-40): 

We disagree that the scientific information supporting the endangerment finding is inadequate. Please 

refer to Section III.A. of the Findings for a discussion of the science on which the decisions are based and 

Section IV.B. for a discussion of how the science was weighed and evaluated, including uncertainty. 

The 2001 NRC report is one of the assessment reports we relied upon in the TSD. The findings of this 

report still represent the state of the science. However, this report is now over eight years old and many 

of its findings have been updated in more recent assessment literature. For example, though NRC 

(2001a) refers to “still uncertain natural variability,” the IPCC (Hegerl et al., 2007) states that it is very 

unlikely (less than 10% probability) that the global pattern of warming observed during the past half 

century is due to only known natural external causes (solar activity and volcanoes) and that globalmean unforced variations on multidecadal timescales are likely (66–90% probability) to be smaller than 

the 20th century global-mean increase in surface temperature. Regarding the “uncertainties in the time 

histories of the various forcing agents and particularly aerosols” indicated by NRC (2001a), we note 

that IPCC (2007d) states with very high confidence (at least 90% certainty) that the global average net 

effect of human activities since 1750 has been one of warming, with a radiative forcing of +1.6 (+0.6 to 

+2.4) W/m2

. Though uncertainties in aerosol contributions to radiative forcing remain, the commenter’s 

assertion that aerosols have become less understood since 2001 is incorrect. In fact, IPCC (Forster et 

al., 2007) states, “Atmospheric models have improved and many now represent all aerosol components 

of significance. Improved in situ, satellite and surface-based measurements have enabled verification of 

global aerosol models.” Although NRC (2001a) stated that health effects of climate change are “poorly 

36 
understood,” we note that many health effects of climate change are well-documented in the most 

recent assessment literature (Confalonieri et al., 2007; CCSP, 2008b; Karl et al., 2009), as described in 

Sections 7 and 8 of the TSD. 

Finally, although NRC (2001a) contains the above cautionary statements which have been updated in 

more recent assessment reports, we note that the report begins with the following statement which 

continues to be broadly consistent with the current assessment literature: “Greenhouse gases are 

accumulating in Earth’s atmosphere as a result of human activities, causing surface air temperatures and 

subsurface ocean temperatures to rise. Temperatures are, in fact, rising.” 

Section II of the Findings discusses how EPA considers uncertainty in making an endangerment decision. 

The apparent criteria suggested by the commenter are not appropriate for the reasons discussed in Section 

II. 

Comment (1-41): 

At least one commenter (3347.1) notes that many of EPA’s predictions depend on a causal chain of 

multiple events occurring. The comment explains that the likelihood of a series of uncertain events is the 

product of their probabilities, which approaches zero as the number of events in the series increases. It 

concludes that EPA cannot base a reasoned decision, even one that does not require certainty or actual 

proof, on data, studies, and assumptions that are of little or unknown reliability. 

Response (1-41): 

The commenter is referring to the concept of propagation of uncertainty, which does not change the 

legitimacy of scientific projections described in the TSD or considered in the Administrator’s 

endangerment finding. The document Guidance Notes for Lead Authors of the IPCC Fourth Assessment

Report on Addressing Uncertainties (see Appendix A of this Volume) directs IPCC (2007) authors to the 

Third Assessment uncertainty guidance document (Moss and Schneider, 2000) and an IPCC workshop 

report (Manning et al., 2004) which discuss this issue. IPCC authors are advised to take into account 

propagation of uncertainty and other potential sources of uncertainty in their statements and findings. In 

other words, the fact that uncertainty accumulates through a chain of causation is reflected and 

communicated in the results presented in the assessment literature (e.g., by describing ranges, levels of 

confidence/certainty). 

The IPCC workshop report (Manning et al., 2004) states that “There is a recognized cascade of 

uncertainty when proceeding through projected climate change, projected effects of that change, and 

projected adaptation or mitigation responses. See Figure 3-1. Dealing with this uncertainty cascade is 

complex and it should not be assumed that uncertainties add in the sense of being statistically 

uncorrelated.” Figure 3-1 shows five uncertainties between emissions and impacts: uncertainty in 

emissions scenarios, in carbon cycle response, in climate sensitivity, in regional scenarios, and in range of 

possible impacts. This figure demonstrates two key issues. One is that there are a limited number of 

uncertainties in the chain, in contrast to the implication of the commenter that the number of events in this 

series is large. Most of the uncertainties in climate change do not depend on each other: for example, 

uncertainty in the dependence of Atlantic hurricane frequency on sea surface temperature changes is 

mostly independent from the uncertainty in the relation between extreme heat events in the Midwest and 

global average temperature increase. Second, the uncertainty is not a “does it exist/does it not exist” 

causal chain of events as described by the commenter, but rather a set of uncertainties that are each 

distributions of outcomes around a central value, with dependence on the previous uncertainty in the 

chain. This means that the central estimate (or median) outcome has little dependence on the number of 

uncertainties in the chain, and also that both tails of these distributions grow as the number of 

uncertainties increase. The final “range of impacts” shows that inclusion of uncertainty should lead to 

37 
higher estimates as often as lower estimates. Figure 10.26 of Meehl et al. (2007) demonstrates these 

attributes of combining uncertainties: it shows global mean temperature projections from six different 

emission scenarios, including uncertainty in carbon cycle response and in the structural parameters of the 

models. There are larger uncertainties when including carbon cycle uncertainties on top of the model 

uncertainties, but these uncertainties lead to higher temperatures than the original distribution as well as 

lower temperatures. 

The CCSP (2009) report Best Practice Approaches for Characterizing, Communicating, and 

Incorporating Scientific Uncertainty in Decisionmaking suggests that propagation of uncertainty can be 

constrained by running an analysis over and over again on a fast computer, using different input values, 

from which it is possible to compile the results into probability distributions. This approach is termed 

“stochastic simulation” or “Monte Carlo.” A number of the studies assessed by the IPCC and CCSP 

reports employed such an approach to quantitatively combine the cascade of uncertainties into output 

probability distributions. 

Therefore, we conclude that the assessment literature has appropriately addressed the well-recognized 

“cascade of uncertainty,” and that the underlying science is sufficiently well characterized for use in 

making reasoned decisions. 

Comment (1-42): 

At least one commenter (3722) argues the Administrator’s conclusions in the Proposed Findings overstate 

scientific understanding of climate change. The comment specifically refers to the following two 

statements: 

It is clear that current and projected levels of greenhouse gases and resultant climate 

change are already and adversely affecting, and will continue to adversely affect, public 

welfare within the meaning of the Act. 

The evidence points ineluctably to the conclusion that climate change is upon us as a 

result of greenhouse gas emissions, that climatic changes are already occurring that harm 

our health and welfare, and that the effects will only worsen over time in the absence of 

regulatory action. 

The commenter concludes that these unequivocal warnings mischaracterize the state of climate science 

and obscure the fundamental uncertainties. 

Response (1-42): 

The specific language highlighted by the commenter has been revised in the Findings. The key science 

from the assessment literature underlying these statements remains strong and accurate. 

Comment (1-43): 

Many commenters (e.g. 0525, 1312, 2895, 2923, 3450.1, 3507.1, 3553.1, 3569.1, 3722, 3915, 4092, 4395, 

7019, 11225, and 11290) question the notion of scientific consensus around the conclusion of humaninduced global warming and/or mention the existence of large numbers of dissenting scientists who have 

reached alternative findings to those of IPCC and CCSP/USGCRP, indicating profound scientific 

uncertainty. As evidence of these dissenting viewpoints, commenters refer to: 

The 35+ scientists who participated in the NIPCC. 

38 
The U.S. Senate Minority Report Update Report of March 17, 2009 (see 

http://epw.senate.gov/public/index.cfm?FuseAction=Minority.Blogs&ContentRecord_id=2674e6

4f-802a-23ad-490b-bd9faf4dcdb7), which states that more than 700 prominent international 

scientists, including many current and former members of the IPCC, disagree with the man-made 

global warming claim. 

A group of more than 31,000 scientists (including 9,021 Ph.D.s) who signed a petition from the 

Oregon Institute of Science and Medicine (http://www.oism.org/pproject/) urging the U.S. 

government to reject the global warming agreement that was written in Kyoto, Japan, in 

December, 1997, and any other similar proposals (petition began in 1998). 

An open letter to the Secretary-General of the United Nations in 2001, signed by over 100 

scientists, statisticians, and economists, urging the United Nations to direct its efforts toward 

dealing with climate change impacts and adaptation, rather than climate change prevention. 

The Manhattan Declaration (ISCC, 2008: 

http://www.climatescienceinternational.org/index.php?option=com_content&task=view&id=37&

Itemid=1), dated March 4, 2008, in which scientists, researchers, economists, and policymakers 

asserted the scientific consensus on climate change is overstated. The signatories recommended 

that world leaders reject the IPCC views and declare that “human-caused climate change is not a 

global crisis.” The Declaration was signed by over 600 individuals. 

At least one commenter (3283.1) indicates that EPA cites consensus without specifically describing the 

meaning and context of that consensus. 

Response (1-43): 

A response to the NIPCC report cited by commenters as evidence of dissenting scientific viewpoints can 

be found at comment response (1-12) in Section 1 of this volume. In addition, please refer to Section 

III.B. of the Findings for a discussion of the science on which the decisions are based. 

We first note that the strength of the science is not determined by petitions or lists of names; rather it is 

determined by the detailed examination of the fully body of literature, as has been done in the assessment 

reports, and as has been done in response to comments throughout the volumes of this Response to 

Comments document. Such a review demonstrates that the scientific basis for the TSD and the 

Administrator’s determination is sound. We respond to the specific petitions below: 

Regarding the U.S. Senate Minority Report listing dissenting scientists, we note that the Center for 

Inquiry1

 recently released a study (Center for Inquiry, 2009: 

http://www.centerforinquiry.net/opp/news/senate_minority_report_on_global_warming_not_credible/) 

which found that 80 percent of “dissenting scientists” in said report had not published peer-reviewed 

climate research. The study also noted that of the report’s purported list of 700 scientists: 

Slightly fewer than 10 percent could be identified as climate scientists. 

Approximately 15 percent had published in the recognizable refereed literature on subjects related 

to climate science. 

Approximately 4 percent appeared to favor the current IPCC-2007 consensus and should not have 

been on the list. 

The Center for Inquiry draws the following conclusions based on its analysis: 

 

1 The Center for Inquiry (http://www.centerforinquiry.net/opp/about) describes itself as a nonpartisan, nonprofit 

501(c)(3) organization that encourages evidence-based inquiry into science, pseudoscience, medicine and health, 

religion, ethics, secularism, and society.

39 
1) We think it is highly unlikely that a growing fraction of top climate scientists are 

becoming increasingly skeptical of human causation of global warming. 

2) We think that the title “Senate Minority Report” is technically appropriate, but grossly 

understated. That report’s list does contain the names of some outstanding scientists, 

including at least one distinguished meteorologist. However, when weighted against the 

much larger number of equally outstanding climate scientists, there is no doubt where the 

great majority of experts in this field stand. 

Though the declarations, petitions, and letters referred to by commenters demonstrate the existence of 

dissenting viewpoints, they do not represent the viewpoints of the overwhelming majority of the active 

climate science research community nor provide legitimate scientific evidence to substantiate the 

alternative points of view presented. For example, though the Oregon Petition is accompanied by a study 

(Robinson et al., 2007) refuting many conclusions of the climate science assessment literature, it is 

published in a medical journal unrelated to climate science. 

We further note a recent polling study (Doran and Zimmerman, 2009) in which researchers found 75 out 

of 77 climatologists who “listed climate science as their area of expertise and who also have published 

more than 50% of their recent peer-reviewed papers on the subject of climate change” believe that human 

activity is a significant factor in changing mean global temperatures. The study concludes: “It seems that 

the debate on the authenticity of global warming and the role played by human activity is largely 

nonexistent among those who understand the nuances and scientific basis of long-term climate 

processes.” 

It is also relevant to point out that many major national and international scientific societies and 

academies have endorsed or expressed support for the findings and conclusions of the assessment 

literature cited by EPA in official statements. The following are some examples: 

Since 2005, the Academies of Science for the G8+5 countries have issued joint statements on the 

threat of climate change. 

o The 2005 statement reported: “...there is now strong evidence that significant global 

warming is occurring. The evidence comes from direct measurements of rising surface air 

temperatures and subsurface ocean temperatures and from phenomena such as increases 

in average global sea levels, retreating glaciers, and changes to many physical and 

biological systems. It is likely that most of the warming in recent decades can be 

attributed to human activities (IPCC 2001). This warming has already led to changes in 

the Earth's climate.” http://www.nationalacademies.org/onpi/06072005.pdf

o The 2007 statement finds: “Recent research strongly reinforces our previous conclusions. 

It is unequivocal that the climate is changing, and it is very likely that this is 

predominantly caused by the increasing human interference with the atmosphere. These 

changes will transform the environmental conditions on Earth unless counter-measures 

are taken.” 

http://www.nationalacademies.org/includes/G8Statement_Energy_07_May.pdf

o The 2008 statement notes: “In 2007 the Intergovernmental Panel on Climate Change 

(IPCC) reaffirmed that climate change is happening and that anthropogenic warming is 

influencing many physical and biological systems” 

http://www.nationalacademies.org/includes/climatechangestatement.pdf

o The 2009 Statement reports: “The IPCC 2007 Fourth Assessment of climate change 

science concluded that large reductions in the emissions of greenhouse gases, principally 

carbon dioxide (CO2), are needed soon to slow the increase of atmospheric 

40 
concentrations, and avoid reaching unacceptable levels. However, climate change is 

happening even faster than previously estimated; global CO2 emissions since 2000 have 

been higher than even the highest predictions, Arctic sea ice has been melting at rates 

much faster than predicted, and the rise in the sea level has become more rapid. 

Feedbacks in the climate system might lead to much more rapid climate changes.” 

http://www.nationalacademies.org/includes/G8+5energy-climate09.pdf

The American Meteorological Society in 2007 stated: “...there is adequate evidence from 

observations and interpretations of climate simulations to conclude that the atmosphere, ocean, 

and land surface are warming; that humans have significantly contributed to this change; and that 

further climate change will continue to have important impacts on human societies, on 

economies, on ecosystems, and on wildlife through the 21st century and beyond.” We further 

note the AMS mentions: “This statement is consistent with the vast weight of current scientific 

understanding as expressed in assessments and reports from the Intergovernmental Panel on 

Climate Change, the U. S. National Academy of Sciences, and the U. S. Climate Change Science 

Program.” http://www.ametsoc.org/policy/2007climatechange.html 

The American Chemical Society writes: “There is very little room for doubt that observed climate 

trends are due to human activities. The threats are serious and action is urgently needed to 

mitigate the risks of climate change.” We note that ACS cites IPCC (2007) as a core reference for 

its statement which is valid for the period 2007–2010. 

http://portal.acs.org/portal/acs/corg/content?_nfpb=true&_pageLabel=PP_SUPERARTICLE&no

de_id=1907&use_sec=false&sec_url_var=region1&__uuid=34a7ad19-6b0b-4720-a706-

e25e4e609d6d

The American Geophysical Union in 2007 writes: “The Earth's climate is now clearly out of 

balance and is warming...With climate change, as with ozone depletion, the human footprint on 

Earth is apparent. The cause of disruptive climate change, unlike ozone depletion, is tied to 

energy use and runs through modern society. Solutions will necessarily involve all aspects of 

society.” http://www.agu.org/outreach/science_policy/positions/climate_change2008.shtml. 

We further note that Alan Leshner, Chief Executive Officer of AAAS, submitted a comment (in response 

to EPA’s ANPR, 1009.1), in which he states: 

...AAAS seeks to offer requested comments on “the best available science for purposes 

of the endangerment discussion.” 

The AAAS Board of Directors approved a statement on climate change in December 

2006 based largely on the Third Assessment Report of the Intergovernmental Panel on 

Climate Change (IPCC) and the 2005 Joint National Academies’ statement. The 

statement, in part, recognizes: 

“The scientific evidence is clear: global climate change caused by human activities is 

occurring now, and it is a growing threat to society. Accumulating data from across the 

globe reveal a wide array of effects: rapidly melting glaciers, destabilization of major ice 

sheets, increases in extreme weather, rising sea level, shifts in species ranges, and more.” 

Since the statement was released, the IPCC Fourth Assessment Report has been released, 

finding greater observed and projected climate change impacts, many of which are cited 

in the ANPR. These are also consistent with the AAAS statement: 

“As expected, intensification of droughts, heat waves, floods, wildfires, and severe 

storms is occurring, with a mounting toll on vulnerable ecosystems and societies. These 

41 
events are early warning signs of even more devastating damage to come, some of which 

will be irreversible.” 

These and other impacts identified in the ANPR reflect the current state of the science, as 

articulated in the consensus documents of the IPCC. This science shows clear impacts to 

society that are occurring now and will continue to grow. 

We hope that the Environmental Protection Agency continues to rely upon this sound 

scientific basis as it moves forward on decisions related to climate policy. 

 

In addition, on October 21, 2009, 18 U.S. scientific societies and/or research institutions (including all of 

those mentioned above) reaffirmed the consensus on climate change in a letter2

 to U.S. senators, stating: 

Observations throughout the world make it clear that climate change is occurring, and 

rigorous scientific research demonstrates that the greenhouse gases emitted by human 

activities are the primary driver. These conclusions are based on multiple independent 

lines of evidence, and contrary assertions are inconsistent with an objective assessment of 

the vast body of peer-reviewed science. Moreover, there is strong evidence that ongoing 

climate change will have broad impacts on society, including the global economy and on 

the environment. For the United States, climate change impacts include sea level rise for 

coastal states, greater threats of extreme weather events, and increased risk of regional 

water scarcity, urban heat waves, western wildfires, and the disturbance of biological 

systems throughout the country. The severity of climate change impacts is expected to 

increase substantially in the coming decades. 

If we are to avoid the most severe impacts of climate change, emissions of greenhouse 

gases must be dramatically reduced. 

These societies and organizations noted that their conclusions “reflect the scientific consensus represented 

by, for example, the Intergovernmental Panel on Climate Change and U.S. Global Change Research 

Program.” They also noted that many scientific societies have endorsed these findings in their own 

statements, including the American Association for the Advancement of Science, American Chemical 

Society, American Geophysical Union, and American Meteorological Society (as documented above), as 

well as the American Statistical Association and Crop Science Society of America. 

Regarding the claim that EPA cites consensus without describing its meaning and context, we disagree. 

Our references to consensus in the TSD and the Findings are consistently within the context of describing 

conclusions of the assessment literature upon which we rely, which are, in fact, consensus-based. The 

Web site (http://www.globalchange.gov/whats-new) for the recent USGCRP assessment (Karl et al., 

2009) notes it represents “a consensus of 13 agencies developed over a year and half.” In its report 

“Understanding and Responding to Climate Change,” the National Academy of Sciences notes that in its 

NRC reports on climate change (which are cited in the TSD) they “have assessed consensus findings on 

the science, identified new avenues of inquiry and critical needs in the observing and computational 

research infrastructure, and explored opportunities to use scientific knowledge to more effectively 

respond to climate change.” The 2005 Joint Science Academies’ statement of 2005 states: “We recognize 

the international scientific consensus of the Intergovernmental Panel on Climate Change (IPCC).” For 

further information on the process involved for developing the consensus conclusions of the IPCC, please 

refer to comment # 1-14. 

 

2 http://www.ametsoc.org/sss/documents/climateletter.pdf 

42 
Comment (1-44): 

To highlight uncertainty in the science, a number of commenters (0482.1, 0591, 0700.1, 3569.1, 3906,) 

reference the scientific testimony of the Right Honorable Christopher Walter Monckton, Third Viscount 

Monckton of Brenchley, before the Energy and Commerce Committee of the House of Representatives on 

March 25, 2009, and/or follow-on letter (addressed to Congressman Joe Barton and Congressman Edward 

Markey), which question the links between human activities and global warming (Monckton, 2009a, 

2009b). One commenter (3906) requests EPA counter any flaws in the letter. 

Response (1-44): 

We respond to the relevant assertions in Lord Monckton’s testimony and in his follow-up letter to 

Representatives Markey and Barton in the appropriate Response to Comment volumes. In his letter, Lord 

Monckton enumerates 50 “red flags” which represent scientific irregularities in statements or conclusions 

made by prominent climate scientists, in the assessment literature, and/or in our TSD. We address most of 

these, but note that some of the “red flags” apply specifically to statements made by individuals (e.g., 

Vice President Al Gore, scientists who testified before Congress, congressional members), which only 

they could reasonably respond to and which we found to be extraneous to the assessment literature and/or 

statements in the TSD. 

Comment (1-45): 

Two commenters (0152, 0718) voice their support for EPA’s Proposed Findings and state that even if the 

full risks and implications of global warming cannot be quantified, EPA has enough information to take 

“concrete and serious steps.” 

Response (1-45): 

We agree with the commenters that the state of the science is strong enough to support the Findings. 

Comment (1-46): 

Several commenters (2972.1, 3136.1, 3449.1, and 3747.1) argue that the TSD does not differentiate 

between the risks to various physical and biological systems specifically resulting from climate change 

and those due to other non-climate pressures including subsidence, land use, development, and population 

growth. Some commenters also state that the TSD overemphasizes climate change pressures, when in 

reality the non-climate pressures are the larger problem. The commenters conclude that because climate 

change is not the only cause of impacts to physical and biological systems and because climate change 

drivers cannot be measurably isolated from other non-climate drivers of impacts, this information cannot 

be used to support the endangerment finding. Commenter 3747.1 argues that EPA’s treatment of these 

baseline assumptions do not meet information quality requirements under the IQA. 

Response (1-46): 

EPA disagrees with the commenters that the information summarized in the TSD does not differentiate 

between climate and non-climate drivers of impacts to physical and biological systems, or adequately 

isolate the observed effects and future risks and impacts attributable to elevated concentrations of GHGs 

and associated climate change, and this issue is addressed extensively throughout the TSD and in the 

Response to Comments document. For example, we describe in Section 5(b) of the TSD the importance 

of considering climate variability and non-climate drivers (e.g., land-use change, habitat fragmentation) in 

order to make robust conclusions about the role of anthropogenic climate change in affecting biological 

and physical systems. The discussions of climate impacts on the sectors described in Sections 7-15 of the 

TSD are also summarized with acknowledgement of the non-climate drivers. As an illustration, in 

43 
Sections 12 and 14, we summarize findings from the assessment literature which discuss impacts to 

coastal areas and ecosystems resulting solely from climate change or from the interaction of both climate 

change and non-climate-related stressors. The discussion in the TSD is clear that climate change effects 

on physical and biological systems do not occur in isolation, and that climate change, other stressors, and 

the compounded effects of both will present new threats while also compounding existing stressors. 

Further, we disagree with the commenter’s statement that our treatment of this issue is inconsistent with 

EPA’s Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility and Integrity of 

Information Disseminated by the Environmental Protection Agency. For EPA’s general response to the 

information quality concerns submitted during the public comment process, please see Section 5 of this 

volume. With respect to this specific issue raised by commenter 3747.1 we note that the Guidelines

encourage risk assessments to analyze and consider ‘real world situations.’ EPA’s approach of assessing 

climate change impacts independently but also in the context of other stressors is therefore consistent with 

the Guidelines. An example of this approach is seen in Section 12(a) of the TSD: 

Although climate change is impacting coastal systems, non-climate human impacts have been 

more damaging over the past century. The major non-climate impacts for the United States and 

other world regions include drainage of coastal wetlands, resource extraction3

, deforestation, 

introductions of invasive species, shoreline protection, and the discharge of sewage, fertilizers, 

and contaminants into coastal waters (Nicholls et al., 2007). The cumulative effect of these nonclimate, anthropogenic impacts increases the vulnerability of coastal systems to climate-related 

stressors. 

EPA also disagrees with the commenters that the TSD inappropriately emphasizes climate change 

pressures. In Section 5(b) of the TSD, we discuss how the IPCC (Rosenzweig et al., 2007) reviewed a 

number of studies that linked changes in some physical and biological systems directly to anthropogenic 

climate change. The IPCC concluded that the observed changes in physical and biological systems “likely

cannot be explained entirely due to natural variability or other confounding non-climate factors” 

(Rosenzweig et al., 2007). Furthermore, future projections of climate change and associated risks and 

impacts in the TSD go even further to isolate the potential effects of climate change, where information 

from the underlying assessment literature often assesses the risks of climate change while holding current 

conditions constant. We therefore find that the TSD’s treatment of climate and non-climate factors was 

reasonable and appropriately reflects the conclusions of the body of scientific literature. 

See Response to Comments Volume 9 for our responses to comments on how specific climate impacts 

evidence was considered in the Administrator’s endangerment finding. 

Comment (1-47): 

A commenter (3747.1) argues that EPA did not adhere to information quality guidelines on 

reproducibility and transparency because the TSD does not explain how EPA determined the probabilities 

assigned to climate science and impacts conclusions from the assessment literature. The commenter 

acknowledges that “adopts IPCC phraseology assessing the likelihood of results” but “never explains how 

it determined the probability.” 

Response (1-47): 

Please see Volume 1: Section 5 of this Response to Comments document for EPA’s general response to 

the information quality concerns submitted during the public comment process. Please see previous 

 

3

 Resource extraction activities in coastal areas include sand/coral mining, hydrocarbon production, and commercial 

and recreational fishing. 

44 
responses to comments in this section regarding our use of the assessment literature’s uncertainty and 

likelihood determinations in the TSD, as well as Section 1 of the TSD, which describes EPA’s approach 

and use of lexicon developed by the IPCC, USGCRP, and CCSP for the consistent communication of 

uncertainty and likelihood. We note that in climate science, likelihood refers to a probabilistic assessment 

of some well-defined outcome having occurred or that will occur in the future (IPCC, 2007e). In this 

sense, likelihood and probability are one and the same. For example, when IPCC authors evaluated the 

likelihood of certain outcomes and determined then to be “very likely,” the probability of occurrence was 

90 to 99%. 

Additional information has been added to Box 1.2 in Section 1 of the TSD to more fully describe our 

approach to the communication of uncertainty and probabilities. Additional detail on these issues is 

provided in prior responses, particularly with respect to the processes followed by IPCC and other 

assessment reports to develop the reports, which includes determining the uncertainty and likelihood 

category to assign to the various scientific issues discussed in the TSD. 

Our characterization and treatment of uncertainty is consistent with EPA’s Guidelines for Ensuring and 

Maximizing the Quality, Objectivity, Utility and Integrity of Information Disseminated by the 

Environmental Protection Agency. Conveying the same likelihood and probability terminology assigned 

to climate science findings by the IPCC and USGCRP/CCSP ensures that the information in the TSD is 

reproducible (the Guidelines state that “EPA intends to ensure reproducibility according to commonly 

accepted scientific, financial, or statistical standards”) and transparent (the Guidelines state that “A higher 

degree of transparency about data and methods will facilitate the reproducibility of such information by 

qualified third parties, to an acceptable degree of imprecision”). 

Comment (1-48): 

Two commenters (3577.1 and 3747.1) discuss how EPA, in general, failed to identify uncertainties in the 

studies that underlie EPA’s Proposed Finding. Commenter 3747.1 argues that EPA did not adhere to 

information quality guidelines by not identifying sources of uncertainty in the climate impacts and models 

described in the TSD. Specifically, the commenter requests that EPA identify: 

The rationale for the Agency’s decision not to identify each of the uncertainties and ranges in the 

studies and models that underlie its proposed endangerment finding. 

What impacts the calculation of recognized uncertainties and ranges would have on the outcome 

of the endangerment finding. 

Response (1-48): 

Please see Volume 1: Section 5 of this Response to Comments document for EPA’s general response to 

the information quality concerns submitted during the public comment process. In addition, please see 

previous responses to comments in this section on EPA’s treatment of uncertainty regarding specific 

issues in the TSD. 

We disagree with the comment that the TSD does not identify uncertainties and present ranges for 

statements of observed and projected climate change. The TSD describes the assessment literature’s 

conclusions regarding the state of the science, discusses key uncertainties with regards to specific climate 

science issues, and presents observations and projections in ranges based upon different emission 

scenarios and other factors specific to a particular climate science issue. For example, Section 6(b) of the 

TSD states: 

The full suite of SRES scenarios (given below) provides a warming range of 3.2°F to 

7.2°F (1.8°C to 4.0°C) with an uncertainty range of 2.0°F to 11.5°F (1.1°C to 6.4°C). The 

45 
multi-model average warming and associated uncertainty ranges for the 2090–2099 

period (relative to 1980–1999) for each scenario, as illustrated in Figure 6.7 are shown in 

Table 6.1: 

Table 6.1: Multi-model Average Warming for the 2090-2099 Period 

Scenario

Average Global Warming by End of 

Century Relative to ~1990 Uncertainty Range

B1 3.2°F (1.8°C) 2.0°F to 5.2°F (1.1°C to 2.9°C) 

A1T 4.3°F (2.4°C) 2.5°F to 6.8°F (1.4°C to 3.8°C) 

B2 4.3°F (2.4°C) 2.5°F to 6.8°F (1.4°C to 3.8°C) 

A1B 5.0°F (2.8°C) 3.1°F to 7.9°F (1.7°C to 4.4°C) 

A2 6.1°F (3.4°C) 3.6°F to 9.7°F (2.0°C to 5.4°C) 

A1FI +7.2°F (+4.0°C) 4.3°F to 11.5°F (2.4°C to 6.4°C) 

The wide range of uncertainty in these estimates reflects the different assumptions about 

future concentrations of GHGs and aerosols in the various scenarios considered by the 

IPCC and the differing climate sensitivities of the various climate models used in the 

simulations (NRC, 2001a; Meehl et al., 2007; Karl et al., 2009). 

Given that the TSD conveys the uncertainty information associated with the assessment literature’s 

conclusions, the commenter’s request to identify each of the uncertainties and ranges in the studies and 

models that underlie the Findings is unnecessary. Our characterization and treatment of uncertainty is 

consistent with EPA’s Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility and 

Integrity of Information Disseminated by the Environmental Protection Agency, because our approach 

maximizes objectivity (which the Guidelines define as “whether the disseminated information is being 

presented in an accurate, clear, complete, and unbiased manner, and as a manner of substance, is accurate, 

reliable, and unbiased”), utility (defined by the Guidelines as “usefulness of the information to the 

intended users”), and transparency (which allows for “the reproducibility of such information by qualified 

third parties, to an acceptable degree of imprecision”). 

Finally, since the TSD appropriately describes uncertainties and presents climate science information in 

ranges, we reject the commenter’s request that EPA reassess the Endangerment Determination. 

1.3 Treatment of Adaptation and Emissions Mitigation 

Comment (1-49): 

A number of commenters (e.g., 2898.1, 3136.1, 3261.1, 3332.1, 3347.1, 3481.1, 3482.1, 3509.1, 3536.2, 

3747.1) state that the Proposal and TSD should have explicitly assessed the potential for adaptation to 

protect public health and welfare from climate change. These commenters argue that observed trends in 

measures of U.S. health and welfare during a time of increasing anthropogenic GHG emissions provide 

evidence of the potential for adaptation to counteract any negative impacts of climate change, and that 

EPA overestimated the negative impacts of future climate change by not considering the role of 

adaptation. A commenter (3126.1), for example, asserts that sensitivity to heat has been declining, air 

quality improving, crop yields increasing, and life spans increasing, and that all this indicates that 

“weather and climate are becoming less and less a negative factor in our overall health and welfare.” 

According to the commenter, “Our adaptations have improved our ability to handle the negative 

consequences of weather while enjoying the positive ones.” 

46 
In arguing that EPA’s approach to adaptation was inadequate or inappropriate for purposes of an 

endangerment analysis, many commenters (e.g., 2898.1, 3136.1, 3261.1, 3332.1, 3347.1, 3394.1, 3482.1, 

3509.1, 3536.2, 3596.1, 3702.1, 3704.2, 3705.1, 3747.1) criticize EPA’s characterization in the Proposal 

of potential policy or societal responses to climate change as speculative. They argue that EPA assumes 

humans will remain passive without changing their behavior or attempting to ameliorate the impacts of 

climate change, while in reality adaptive measures are all but inevitable. 

Two commenters (3347.1 and 3509.1) state: 1) that autonomous adaptation affects the severity of 

impacts; 2) that anticipatory adaptation affects the likelihood of impacts; and 3) that both should therefore 

have been considered in the Proposal. One of these commenters (3509.1) characterizes the decision not to 

consider adaptive effects as “erroneous and clearly arbitrary.” 

Finally, several commenters (e.g., 3332.1, 3536.2, and 3747.1) argue that EPA should explicitly consider 

not just potential adaptations but also mitigation strategies, including their potential to prevent harm. 

These commenters assert that it is unreasonable for EPA to assume that society will not undertake 

mitigation in future. 

Response (1-49):

See Section III.C, “Adaptation and Mitigation,” of the Findings for our response to comments on the 

treatment of adaptation and mitigation in the Findings. 

Comment (1-50): 

Two commenters (2898.1 and 3394.1) state that EPA should explicitly consider potential private 

adaptation and critiqued the following statement from the Proposal: “Just as the Administrator would not 

consider, for example, the availability of asthma medication in determining whether criteria air pollutants 

endanger public health, so the Administrator will not consider private behavior in the endangerment 

determination at hand.” A commenter (3394.1) states that the argument is “not a relevant analogy to 

adaptation in the context of climate” and that the availability of asthma medication in determining 

whether criteria air pollutants endanger public health “is not comparable to evolutionary responses in 

natural ecosystems or to changes in human behavior that may prevent welfare or indirect health impacts 

from ever occurring at all.” The commenter also states that “in a variety of other settings, EPA has 

promulgated regulations and implemented policies to encourage adaptive responses to what might have 

otherwise developed into adverse public health and welfare impacts.” 

A commenter (2898.1) equates EPA’s decision not to consider potential private adaptation to a catch-22, 

stating that EPA’s reasoning for not explicitly considering adaptation implies that if people are anticipated 

to be worse off, that constitutes endangerment, but if people are reasonably anticipated to be better off, 

albeit due to adaptation, that also constitutes endangerment. According to the commenter, this reasoning 

guarantees an endangerment finding regardless of the risks people actually face. The commenter 

additionally questions whether EPA’s reasoning implies that we are all endangered, all the time, 

mentioning that there are very few places on Earth where people can be healthy and thriving without 

forms of private adaptation to climate such as clothing, shelter, and agriculture. 

Response (1-50): 

See Section III.C, “Adaptation and Mitigation,” of the Findings for our response to comments on the 

treatment of adaptation and mitigation in the Findings. 

The specific statement from the Proposal critiqued by commenters 2898.1 and 3394.1 is not included in 

the revised discussion of adaptation included in the finding, where we have provided additional 

clarification on our treatment of adaptation and mitigation (see Section III.C). The discussion of 

47 
adaptation and mitigation in Section III.C of the Findings encompasses our treatment of all forms of 

adaptation. 

In any case, the commenter presents a false comparison, assuming that climate change combined with 

future adaptation would lead to people being better off. Nothing in the evidence before EPA or the 

comment would lead to that conclusion. The commenter also mischaracterizes EPA’s position—EPA is 

not determining whether climate or climate change endangers people, assuming we remove all present 

social circumstances of housing, infrastructure, and the like. EPA’s position is that while future 

adaptation or mitigation may well occur, it does not change the issue before EPA—does the air pollution 

endanger public health or welfare, without considering future planned adaptation or mitigation? The 

reasons for this approach are described in Section III.C. of the Findings. 

Finally, when we do not respond to comments on specific adaption or mitigation issues in the various 

volumes of this Response to Comments document, it should not be interpreted as our agreeing with the 

assertions of the commenter. We are not responding because it is not relevant to the Findings; we are not 

agreeing or disagreeing with the commenter on those issues. 

Comment (1-51): 

Several commenters (3347.1, 3379.1, 3482.1, 3509.1, 3702.1, 3705.1) cite the following quotation from 

the TSD (itself a quotation from the CCSP report on human health): “The United States is certainly 

capable of adapting to the collective impacts of climate change.” These commenters argue that the 

quotation is highly relevant to the likelihood and severity of public health– or welfare-related effects of 

climate change in the United States, that an endangerment analysis must seek to determine what type and 

extent of harm is likely to occur, and that this question cannot be answered while ignoring the role of 

adaptation. 

Response (1-51): 

See Section III.C, “Adaptation and Mitigation,” of the Findings for our response to comments on the 

treatment of adaptation and mitigation in the Findings. 

With respect to this specific quote, it is incorrect to interpret its inclusion in the TSD as evidence that 

there are not risks to health and welfare. Further, the commenters only included one sentence of the 

section from which the quotation was drawn. The following sentence in the TSD states: “However, there 

will still be certain individuals and locations where the adaptive capacity is less and these individuals and 

their communities will be disproportionally impacted by climate change.” For EPA’s responses to 

comments and literature provided on specific climate impacts summarized in the TSD, please refer to the 

appropriate Response to Comment volumes. 

Comment (1-52): 

A commenter (3347.1) asserts that it is inconsistent and arbitrary for EPA to consider autonomous 

adaptation trends by non-human life forms while disregarding human adaptation in reaching its 

conclusion. The commenter argues that the TSD selectively describes some adaptive responses that are 

likely to occur as a result of climate change, such as a shift of species to northern and higher elevations, 

while omitting potentially more important adaptive response. The commenter states that “EPA’s decision 

to broadly exclude other adaptive responses, including autonomous and anticipatory adaptive responses 

that could undermine the proposed endangerment finding, is arbitrary and represents a bias at odds with 

an objective with an objective analysis of risks.” 

48 
Response (1-52): 

See Section III.C, “Adaptation and Mitigation,” of the Findings for our response to comments on the 

treatment of adaptation and mitigation in the Findings. 

The TSD summarizes key observations from the assessment literature regarding natural autonomous 

adaptation; however, the decision not to include information on planned adaptation in the TSD was not 

based on arbitrary or biased reasons. Autonomous adaptation4

 is distinct in several ways from potential 

planned adaptations and merits different treatment. 

First, observed non-human autonomous adaptations are part of the physical changes among ecosystems 

and wildlife in response to climate change. Second, in contrast to planned adaptations, autonomous 

adaptations are not a conscious response by society to climatic stimuli. Rather, they are natural physical 

responses to changes in the climate that occur independently of any potential human responses, thus 

representing an important strand of physical evidence that global climate is changing. 

There are cases in the TSD where some degree of human autonomous adaptation is accounted for. These 

cases occur where the literature on which the TSD relies already uses assumptions about autonomous 

adaptation when projecting the future effects of climate change. Such cases are noted in the document. 

Comment (1-53): 

A commenter (3702.1) asserts that other agencies routinely consider adaptive behavior in their regulatory 

decision-making and stated that NOAA recently considered the past and likely future responsible 

behavior of ribbon seals in deciding whether to list the seal species as threatened or endangered. 

Response (1-53): 

See Section III.C, “Adaptation and Mitigation,” of the Findings for our response to comments on the 

treatment of adaptation and mitigation in the Findings. In addition, see the previous response to comments 

regarding autonomous adaptation. 

We further note that the legal requirements governing an endangerment analysis under Section 202(a) of 

the CAA are distinct from those governing different types of actions undertaken by other agencies. 

Section II of the Findings discusses the criteria under Section 202(a), and Section III.C. discusses 

adaptation and mitigation. 

Comment (1-54): 

A commenter (3136.1) argues that the TSD’s “use of [hurricane] Katrina as an ‘adaptation is inadequate’ 

example completely misses the point.” The commenter states that Katrina “was in no way a 

climatologically remarkable storm in New Orleans” and was “more an indictment of government 

emergency response than our adaptive capacity.” 

Response (1-54):

See Section III.C, “Adaptation and Mitigation,” of the Findings for our response to comments on the 

treatment of adaptation and mitigation in the Findings. 

 

 

4

 IPCC defines autonomous adaptation as adaptation that does not constitute a conscious response to climatic stimuli 

but is triggered by ecological changes in natural systems and by market or welfare changes in human systems. Also 

referred to as spontaneous adaptation. 

49 
We note that the question of whether hurricane Katrina was “climatologically remarkable” is not germane 

to our reasons for determining that planned adaptation and mitigation are outside the scope of the 

endangerment finding. For discussion of hurricane Katrina in relation to climate change and climate 

change impacts, please refer to Sections 7(b), 12(a), 12(b), and 13(b) of the final TSD. For EPA’s 

responses to comments on extreme weather events in relation to climate change, please refer to Volume 2, 

Section 2.6: “Extreme Weather Events,” and Volume 4, Section 4.5, “Projections of Extreme Weather 

Events.” 

Comment (1-55): 

Two commenters (2818 and 4036.5) state that adaptation is not sufficient to prevent harm from climate 

change. A commenter (2818) argues that adaptation is important but inadequate on its own. The 

commenter states that though they think adaptation is important, “all the adaptation in the world is not 

going to save us, unless we also work to get the climate stabilized.” Another commenter (4036.5) states 

that there are some impacts of climate change for which adaptation is simply not an option and cited as an 

example injuries related to extreme weather events that are simply not treatable with medication. 

Response (1-55): 

See Section III.C, “Adaptation and Mitigation,” of the Findings for our response to comments on the 

treatment of adaptation and mitigation in the Findings. 

Comment (1-56): 

A commenter (3747.1) argues that EPA ignored the potential impacts of adaptive behaviors or GHG 

mitigative actions in reducing impacts to humans and the environment, therefore not adhering to 

information quality guidelines. The commenter argues that EPA’s lack of consideration on adaptation and 

mitigation resulted in vulnerabilities being overstated and conclusions that were biased and incomplete. 

Response (1-56): 

See Section III.C, “Adaptation and Mitigation,” of the Findings and previous responses to comments in 

this section regarding EPA’s treatment of adaptation and mitigation in the Findings. EPA has provided a 

high level of transparency and consistency in accordance with EPA’s Guidelines for Ensuring and 

Maximizing the Quality, Objectivity, Utility and Integrity of Information Disseminated by the 

Environmental Protection Agency. Through the clear description of our treatment of adaptation and 

mitigation in the Introduction of the TSD, we have been transparent and open with the approach used. 

This approach is also consistent with the Guidelines because the TSD was peer-reviewed by external 

climate science experts. Given our approach to the scientific literature (described in Section III.A of the 

Finding), the purpose of the federal expert review was to ensure that the TSD accurately summarized the 

conclusions and associated uncertainties from the assessment reports. Their unbiased and comprehensive 

review of the TSD revealed that our treatment of adaptation and mitigation was appropriate and sound, 

and that we appropriately applied and summarized the information from the assessment literature. This 

ensured that the climate change risk and impacts information was appropriately presented and that 

vulnerabilities were not overstated. 

Comment (1-57): 

Commenter 2898.1 cites a presentation by Indur Goklany (2006) to argue that mortality in the U.S. due to 

extreme weather events is currently below its peak levels of a few decades ago, and that a reversal of 

these trends is not reasonably anticipated, even if one assumes that global warming will affect extreme 

weather. The commenter agrees with EPA that heat waves are likely to become more intense but asserts 

50 
that more heat waves will not lead to more heat-wave related mortality, due to adaptive actions. The 

commenter cites a paper (Davis et al., 2003) which they claim shows that as urban air temperatures have 

increased, due to expanding urban heat islands, cities where hot weather is common have had practically 

no heat-related mortality. 

Response (1-57): 

See Section III.C, “Adaptation and Mitigation,” of the Findings for our response to comments on the 

treatment of adaptation and mitigation in the Findings. 

See Volume 5 of the Response to Comments document for EPA’s response to the specific comments and 

literature provided on heat mortality and morbidity. 

1.4 Consideration of Net (Adverse and Beneficial) Effects 

Comment (1-58): 

A number of commenters (e.g., 3384.1, 3411.1, 3440.1, 3449.1, 3473.1, 3481.1, 3530.1, 4395, 7020, 

9636, 10144, 11315, 11449) argue that EPA failed to adequately identify and consider the potential 

benefits of elevated atmospheric GHG concentrations and climate change. One commenter (11315), for 

example, states: “EPA acknowledges that there are beneficial impacts from increase [sic] carbon dioxide 

(the dominant man induced greenhouse gas) but fails to adequately identify them or their significance.” 

Other commenters (3283.1, 3324.1, and 3340) contend that the TSD contains biased language that focuses 

on the worst-case potential harm, over-emphasizes negative impacts, and has not adequately attempted to 

evaluate the potential benefits of climate change. 

A number of commenters (e.g., 0400, 0401.3, 0455, 1216.1, 1561.1, 2157, 2750, 2883.1, 2893, 3071, 

3214.1, 3261.1, 3261.2, 3307.1, 3395.1, 3722, A29, 8978.1, 10158, 1217.1, 11315, 11492) state that the 

benefits of elevated atmospheric GHG concentrations and climate change outweigh the adverse effects. 

Some of these commenters assert that climate change will result in net economic benefits for the United 

States. In addition, commenters describe a variety of sector-specific benefits that they believe will result 

from elevated atmospheric CO2 concentrations and warming temperatures, including: reduced health 

impacts from cold temperatures that, according to commenters, could outweigh increased risks from heat 

(e.g., 0400, 0798, 3307.1, 3384.1, 3411.1, 4632R51, 9946, 11453.1); a potential for fewer tropical 

cyclones (e.g., 0400); positive effects on plant growth (e.g., 0455, 2883.1, 3061, 3214.1,); increased crop 

and food production (e.g., 0798, 1216.1, 1217.1, 1561.1, 3214.1, 3261.1, 3395.1, 4632R51, 10158, 

9061.1); and decreases in heating use and costs (e.g., 2883.1, 4632R51). Several commenters (e.g., 3224) 

states that warming to date has been accompanied by increasing life spans, increases in GDP, and 

increases in food production/supplies despite increases in population. Another commenter (0700.1) 

asserts that temperature differentials that cause storms diminish with warming. 

Response (1-58): 

We reviewed the TSD in light of this comment, and find that the TSD summarizes both beneficial and 

adverse impacts, drawing from the findings in the assessment literature. The TSD includes information 

regarding potential benefits of warming with respect to heat- and cold-related mortality in Section 7; 

effects of elevated CO2 concentrations on the agriculture and forestry sectors in Sections 9 and 10; and 

impacts of warmer temperatures for energy use, including heating requirements, in Section 13. Thus, 

EPA does not agree that the TSD contains biased language or does not provide a balanced and reasonable 

evaluation of both the beneficial and adverse impacts of climate change. 

51 
The impacts of changes in tropical cyclone activity are discussed in Section 7(b) of the TSD. Potential 

changes in storms are addressed in Section 6(e) of the TSD, and see also our responses to comment in 

Volume 4 of this Response to Comments document. 

We received many comments and, in some cases, additional literature related to the characterization in the 

TSD of specific impacts associated with elevated atmospheric GHG concentrations. For EPA’s responses 

to these comments, please refer to the appropriate Response to Comment volumes. For EPA’s responses 

to comments pertaining to the method used by the Administrator to find endangerment, please refer to 

Volume 9. 

Comment (1-59): 

Several commenters (e.g., 0603.1, 3411.1, 3607.1, 3722, 10144) state that EPA did not explicitly enough 

quantify positive and negative effects from elevated GHG concentrations and climate change to 

adequately support the Proposed Findings. A commenter (3603.1), for example, states that EPA should 

more thoroughly characterize, using numbers and ranges, the health and welfare impacts. Another 

commenter (3722) states that EPA should have evaluated in detail, in a balanced and complete fashion, 

the net effect of warming temperatures in determining whether warming will result in adverse health 

effects, taking into account both the positive and negative impacts. Two commenters (3322.2, 10144) 

request that EPA assess and quantify the beneficial impact on climate change and the resultant 

improvements to public health/safety and welfare associated with regulating GHG emissions under the 

CAA. 

Response (1-59): 

We disagree that we did not explicitly enough quantify the effects of elevated GHG concentrations and 

associated climate change, including development of numbers and ranges. Our treatment of positive and 

negative effects from warming and other climatic changes is consistent with the assessment literature and 

fully appropriate for purposes of an endangerment finding. We quantified impacts where possible, but we 

did not do so in cases where it cannot be done in a scientifically rigorous manner. The assessment 

literature on which the TSD is primarily based does not numerically quantify the impact of every 

observed and projected change due to elevated GHG concentrations and associated climate change, nor 

does the TSD. 

As demonstrated by the assessment literature, it is possible and useful to assign confidence levels to many 

impact statements, findings, and projections. For this reason, the TSD employs terminology consistent 

with the assessment reports upon which it is primarily based to communicate likelihoods and 

uncertainties for impacts in each sector (see Section 1.2 of this volume and Box 1.2 of the TSD for a 

discussion of communication of uncertainty in the IPCC and CCSP/USGCRP reports). 

For a discussion of key issues the Administrator considered when evaluating the state of the science, 

including her consideration of the nature and potential magnitude of the impacts (both adverse and 

beneficial) across all climate-sensitive elements of public health and welfare, please refer to Volume 9 of 

this Response to Comments document and Section IV.B of the Findings. For EPA’s responses to 

comments on impacts in specific sectors, please refer to the appropriate Response to Comment volumes. 

1.5 Information Quality Act Requirements for Independent Assessment 

Comment (1-60): 

52 
A number of commenters argue that EPA has not complied with the objectivity, utility, and integrity 

guidelines of the IQA and EPA Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility 

and Integrity of Information Disseminated by the EPA.5

 Many commenters went on to explain specific 

concerns regarding information quality, including EPA’s use of the synthesis literature reports. 

Response (1-60): 

EPA has fully complied with the requirements of the IQA (also referred to as the Data Quality Act) and 

the CAA. The IQA requires the Office of Management and Budget and federal agencies to issue 

guidelines that “ensur[e] and maximize[e] the quality, objectivity, utility, and integrity of information 

(including statistical information) disseminated by Federal agencies” (Public Law 106-554; 44 U.S.C. 

3516, note). The IQA does not impose its own standard of “quality” on agency information; instead, it 

requires only that an agency “issue guidelines” ensuring data quality. Following guidelines issued by the 

Office of Management and Budget, EPA released its own guidelines to implement the IQA 

(http://www.epa.gov/QUALITY/informationguidelines/documents/EPA_InfoQualityGuidelines.pdf). 

These guidelines describe thorough mechanisms under which the Agency may review data quality. In 

addition to complying with the requirements of the IQA, EPA has acted consistently with the applicable 

information quality guidelines.

For EPA’s responses to comments on specific information quality concerns raised by the commenters, 

please see responses in this Section, other sections in this Volume, and relevant Response to Comment 

volumes. 

Comment (1-61): 

One commenter (3747.1) argues that EPA has not complied with the IQA and submits 13 separate 

information quality concerns (labeled “requests for correction” by the commenter) related to the 

following topics: peer review; treatment of uncertainty and ranges; selection of cited studies; transparency 

of available data; transparency in observational data; transparency in model limitations; baseline 

assumption errors; adaptation/mitigation; defining likelihood; misapplication of IPCC storylines; 

availability of data; precipitation; and sea level rise. For each topic, the commenter provides an argument, 

along with specific information quality concerns regarding the data and information used in the TSD and 

Findings. In their submission, the commenter (3747.1) states: “We recognize that EPA has the right to 

respond to these findings with its response to comments as these RFCs [requests for correction] are being 

submitted within an open comment period. [The commenter] is willing to forego an individual response 

and, to the contrary, believes that stakeholders and the public would benefit from EPA’s responses and 

corrections.” 

Response (1-61): 

As a preliminary matter, other commenters, such as 3394.1, suggest that the comments were filed as 

“requests for correction” (RFCs) during this proposal. Any such RFCs in this instance have been treated 

as comments on the proposed rule and have been considered and addressed as such. The comments will 

not be assigned an RFC number by EPA. 

Consistent with the statement of the commenter (3747.1), Section 8.5 of EPA’s Guidelines for Ensuring 

and Maximizing the Quality, Objectivity, Utility and Integrity of Information Disseminated by the 

Environmental Protection Agency, describes that if a group or an individual raises a question regarding 

information supporting a proposed rule, EPA generally expects to treat it procedurally like a comment to 

the rulemaking, addressing it in the response to comments rather than through a separate response 

 

5 Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility and Integrity of Information 

Disseminated by the Environmental Protection Agency. EPA/260R-02-008, October 2002.

53 
mechanism. When EPA provides opportunities for public participation by seeking comments on 

information, the public comment process will generally address concerns about EPA’s information. EPA 

believes that the thorough consideration provided by the public comment process for these Findings 

serves the purposes of the Guidelines, provides an opportunity for correction of any information that does 

not comply with the Guidelines, and does not duplicate or interfere with the orderly conduct of the action. 

After careful review, EPA concluded that it is most appropriate to treat these 13 separate topics of 

concern as public comments and fully address them in the relevant volumes of the Response to 

Comments document. In many cases, other commenters raised analogous points and we have grouped 

these similar comments, where appropriate, for purposes of our response. Please see the following 

volumes of this Response to Comments document for our responses to these requests for correction: 

Request for Correction: Peer Review This section (1.5) 

Request for Correction: Treatment of Uncertainty and Ranges Volume 1: Section 2 

Request for Correction: Selection of Cited Studies This section (1.5) 

Request for Correction: Transparency of Available Data This section (1.5) 

Request for Correction: Transparency in Observational Data This section (1.5) 

Request for Correction: Transparency in Model Limitations Volume 4 

Request for Correction: Baseline Assumption Errors Volume 1: Section 2 

Volume 3 

Request for Correction: Adaptation/Mitigation Volume 1: Section 3 

Request for Correction: Defining Likelihood Volume 1: Section 2 

Request for Correction: Misapplication of IPCC Storylines Volume 4 

Request for Correction: Availability of Data This section (1.5) 

Request for Correction: Precipitation Volume 2 

Volume 7 

Request for Correction: Sea Level Rise Volume 2 

The process used by EPA regarding the information that forms the basis for the Findings maximizes 

quality, utility, objectivity, and integrity of the information used. 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. Therefore, and as further explained below, we have addressed these topics of concern 

consistent with EPA’s Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility and 

Integrity of Information Disseminated by the Environmental Protection Agency. 

Comment (1-62): 

A number of commenters (0289, 3332.1, 3394.1, 3415.1, 3509.1, 3577.1, 3747.1, 7029, 10345, 10524, 

10956, 11358.1, and 11466.1) argue that EPA did not make publically available the data, models, and 

other relevant information used in the studies upon which the endangerment determination was made. 

Several commenters (3577.1, 3747.1, and 10071.2) state that nearly half of the studies on which EPA 

relies for the Proposed Findings are unavailable in the docket due to copyright issues. 

Response (1-62): 

EPA is required to docket only the information on which it relies, and as explained Section III.A. of the 

Findings, and in this volume of the Response to Comments document, the Administrator is reasonably 

relying on the major assessments of the USGCRP, IPCC, and NRC as the primary scientific and technical 

basis of her endangerment decision. See, e.g., American Trucking Ass’n v. EPA, 293 F.3d 355, 372 (D.C. 

Cir. 2002) (“ATA III”) (EPA is not required to obtain and publicize the data underlying all the studies on 

which they rely.). See Section III.A. of the Findings, “The Science on Which the Decisions Are Based,” 

54 
for our response to comments on the use of the assessment literature. Further, as noted previously, Section 

1(b) and Box 1.1 of the TSD provide a general description of the procedures followed by the IPCC and 

USGCRP/CCSP in developing their reports, and our responses to specific comments on these issues are 

provided in Section 1.1 of Volume 1 (this volume) of the Response to Comments document. 

Where EPA used or described any data in the TSD, for example the GHG emissions data, the source of 

the data is listed, including where it can be accessed and downloaded. Further, each report, study, or 

dataset we relied upon has been placed in the Docket6

 for this Action. Information regarding the 

underlying data, models, and studies used by IPCC, USGCRP, CCSP, and NRC in developing their 

assessment reports can be accessed by consulting these reports. Given that some of these reports relied 

upon thousands of underlying studies, supplying every underlying study in the Docket would be 

unreasonable and unnecessary. 

With respect to the comment regarding the reliance of copyrighted materials, we acknowledge that more 

than half of the scientific literature that EPA references in the TSD has copyright protections and is 

therefore unavailable for download from the Docket at regulations.gov. However, the public can review 

all documents used by EPA in developing the TSD by requesting a copy or visiting EPA’s Air Docket. 

EPA practice regarding the availability of copyrighted materials is consistent with law. The online Docket 

provides the public with an explanation of why certain copyrighted material is not available for download 

and provides information on how to receive copies of the copyright protected material. The following 

message is posted for each copyrighted publication in the Docket: 

This document is not available in Regulations.gov since it is a copyrighted publication 

and may not be reproduced without consent of the copyright holder. Contact the EPA 

Docket Center, Public Reading Room to view or receive a copy of this document. 

Requests for copies may be made as follows: 

In person/writing: 

Environmental Protection Agency, Docket Center 

1301 Constitution Ave NW, 2822T, Room 3334 

Washington, DC. 20004 

Telephone: 

202-566-1744 

Fax: 

202-566- 9744 

Email: 

docket-customerservice@epa.gov 

All sources of information from the assessment reports are clearly cited in the text of the TSD and listed 

in the references section. This approach ensures the high level of transparency and consistency that is 

encouraged by EPA’s Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility and 

Integrity of Information Disseminated by the Environmental Protection Agency, and will ensure “the 

reproducibility of such information by qualified third parties, to an acceptable degree of imprecision.” 

Comment (1-63): 

 

6

 EPA Docket ID # EPA-HQ-OAR-2009-0171. 

55 
A commenter (3747.1) argues that EPA did not adhere to information quality guidelines under the IQA 

because it did not provide the following regarding the data and models used in the TSD: 

Raw data sets used in the analysis of the observational record. 

Algorithms used to correct, transform, or otherwise modify observational datasets. 

Missing data algorithms for all datasets. 

Datasets used to calibrate models. 

Model calibration results for models. 

Adjustments made to models as a result of calibration. 

Response (1-63):

As previously noted, the IQA does not impose its own standards or establish any requirements regarding 

the quality of agency information; instead, it requires only that an agency “issue guidelines” ensuring data 

quality. EPA complied with the IQA by issuing its Guidelines for Ensuring and Maximizing the Quality, 

Objectivity, Utility and Integrity of Information Disseminated by the Environmental Protection Agency

and has acted consistently with these Guidelines in developing these Findings. 

As noted above, EPA is required to docket only the information on which it relies, and the Administrator 

is reasonably relying on the major assessments of the USGCRP, IPCC, and NRC as the primary scientific 

and technical basis of her endangerment decision. EPA did not conduct new research or modeling in 

developing the TSD, and instead relied upon the findings of the assessment literature, including data and 

modeling studies presented in those reports. The information mentioned by the commenter can be 

accessed by consulting these assessment reports and the underlying studies. For example, Lemke et al. 

(2007) describes that “The premier data set used to evaluate large-scale snow covered area (SCA), which 

dates to 1966 and is the longest satellite-derived environmental data set of any kind, is the weekly visible 

wavelength satellite maps of NH [Northern Hemisphere] snow cover produced by the US National 

Oceanic and Atmospheric Administration’s (NOAA) National Environmental Satellite Data and 

Information Service (NESDIA; Robinson et al., 1993).” The Guidelines state: “For disseminated 

influential original and supporting data, EPA intends to ensure reproducibility according to commonly 

accepted scientific, financial, or statistical standards. It is important that analytic results for influential 

information have a higher degree of transparency regarding (1) the source of the data used, (2) the various 

assumptions employed, (3) the analytic methods applied, and (4) the statistical procedures employed.” 

Our comprehensive referencing of the assessment literature ensures transparency regarding the source of 

the data used and the TSD clearly indicates assumptions (e.g., emissions scenarios), analytical methods, 

and statistical procedures where that information was necessary in describing the conclusions. 

Comment (1-64): 

A number of commenters (0169, 2972.1, 3187.1, 3286.1, 3297.1, 3307.1, 3332.1, 3347.1, 3372.1, 3394.1, 

3415.1, 3481.1, 3579.1, 3596.1, 3705.1, 3722, 3747.1, 3748.1, 4446, 4766, and 9970) argue that EPA did 

not following IQA guidelines when it decided not to conduct a new analysis of the best available 

scientific information and instead relied upon IPCC and CCSP assessments. 

Response (1-64): 

See Section III.A. of the Findings, “The Science on Which the Decisions Are Based,” and Section 1.1 of 

this volume of the Response to Comments document, for our responses on the use of the assessment 

literature and EPA’s decision not to conduct an additional and separate review of the underlying climate 

data and research. 

56 
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. The Guidelines state: “Ensuring 

and maximizing the quality of information from States, other governments, and third parties is a complex 

undertaking, involving thoughtful collaboration with States, Tribes, the scientific and technical 

community, and other external information providers. EPA will continue to take steps to ensure that the 

quality and transparency of information provided by external sources are sufficient for the intended use.” 

Our approach is consistent with these guidelines because we thoroughly reviewed and evaluated the 

author selection, report preparation, expert review, public review, information quality, and approval 

procedures of IPCC, USGCRP/CCSP, and NRC to ensure the information adhered “to a basic standard of 

quality, including objectivity, utility, and integrity.” See responses to comments in Section 1 and 

Appendices A, B, and C of this Volume for additional information regarding the steps EPA took to ensure 

that the quality and transparency of information provided by these assessments. See Section III.A of the 

Findings for our rationale for why the assessment literature represents the best available scientific 

information regarding climate change. 

Comment (1-65): 

A commenter (3747.1) argues that they are unable to evaluate the strength of EPA’s analysis of 

observational data because the TSD does not describe the “current state of observational data in detail, 

including uncertainties in data collection, data assembly, data processing, correction factors, and data set 

concatenations.” The commenter argues that EPA did not conform to information quality guidelines. 

Response (1-65):

As previously noted, the IQA does not impose its own standards or establish any requirements regarding 

the quality of agency information; instead, it requires only that an agency “issue guidelines” ensuring data 

quality. EPA complied with the IQA by issuing its Guidelines for Ensuring and Maximizing the Quality, 

Objectivity, Utility and Integrity of Information Disseminated by the Environmental Protection Agency

and has acted consistently with these Guidelines in developing these Findings. 

In developing the TSD, EPA primarily relied upon the findings of the assessment literature, including 

observational data and studies describing observed climate change impacts. We did not develop new 

observational data as part of this action, but rather summarized existing information from the assessment 

literature. The specific information regarding observational data mentioned by the commenter can be 

accessed by consulting these assessment reports and the underlying studies. This approach is consistent 

with EPA’s Guidelines. 

See Section III.A., “The Science on Which the Decisions Are Based,” and Section 1.1 of this volume of 

the Response to Comments document, for our responses on the use of the assessment literature, our 

evaluation of the procedures for developing the IPCC and other assessment reports, the treatment of new 

and additional scientific studies received through the public comment process, and EPA’s decision not to 

conduct an additional and separate review of the underlying climate data and research. See Section 1.2 of 

this volume for EPA’s response to comments on the communication of uncertainties in the underlying 

assessment literature. 

Comment (1-66): 

A commenter (11466.1) describes that surface temperature data from the University of East Anglia’s 

Climate Research Unit (CRU) was used by EPA in the TSD and that the raw data no longer exist, as only 

the quality-controlled and homogenized data was retained by CRU. The commenter argues that use of this 

57 
data violates EPA’s information quality guidelines, as the public is unable to access, assess, and verify the 

data. 

Response (1-66): 

EPA’s response to this comment is provided in Volume 2: Section 2 of this Response to Comments 

document. 

Comment (1-67): 

A number of commenters (0169, 0797, 2972.1, 3053, 3136.1, 3187.1, 3187.4, 3286.1, 3297.1, 3307.1, 

3332.1, 3347.1, 3372.1, 3394.1, 3415.1, 3481.1, 3509.1, 3596.1, 3597.1, 3679.1, 3705.1, 3722, 3747.1, 

3748.1, 3764.1, 3769.1, 4766, 10388) argue that EPA did not adhere to information quality guidelines in 

using IPCC, CCSP, and NRC reports as the basis of the endangerment finding. Most of these comments 

argue that EPA did not consider all relevant information before proposing the findings and failed to be 

transparent regarding the Agency's process for evaluating and considering scientific literature in 

developing the Proposed Findings. Commenter 3747.1 argues that EPA should more clearly describe the 

process used in selecting studies and information which were cited in the TSD. 

Response (1-67): 

EPA has clearly explained how it evaluated and considered scientific literature, and therefore has adhered 

to the information quality guidelines, as further explained in the Findings and the Response to Comments 

document. See Section III.A. of the Findings, “The Science on Which the Decisions Are Based,” and 

Section 1.1 of this volume of the Response to Comments document, for our responses on the use of the 

assessment literature as scientific basis in the TSD, our evaluation of the procedures used by IPCC, 

USGCRP, CCSP, and NRC in developing the assessment reports, the treatment of new and additional 

scientific studies received through the public comment process, and EPA’s decision not to conduct an 

additional and separate review of the underlying climate data and research . See Section IV of the 

Findings for detailed discussion of how the Administrator reached her determination. This section of the 

Findings was substantially expanded in response to comments. 

Comment (1-68): 

Several commenters (0322, 3286.1, 3297.1, 3330.1, 3379.1, 3394.1, 3415.1, 3705.1, and 3764.1) argue 

that EPA has not shown that the IPCC's information quality process is equivalent to requirements under 

the IQA. 

Response (1-68): 

As previously noted, the IQA does not impose its own standards or establish any requirements regarding 

the quality of agency information; instead, it requires only that an agency “issue guidelines” ensuring data 

quality. EPA complied with the IQA by issuing its Guidelines for Ensuring and Maximizing the Quality, 

Objectivity, Utility and Integrity of Information Disseminated by the Environmental Protection Agency

and has acted consistently with these Guidelines in developing these Findings. 

See Section III.A. of the Findings, “The Science on Which the Decisions Are Based,” for our responses 

on the use of the assessment literature and our evaluation of the procedures used by IPCC, USGCRP, 

CCSP, and NRC in developing the assessment reports. As thoroughly discussed in our response to 

comment 1-14, the IPCC process for preparation and review of its reports demonstrate a formal and 

sustained commitment to transparency and rigor in report development, review, and acceptance and 

approval. The assessment reports we used in developing the TSD represent the best available science and 

58 
supporting studies conducted in accordance with sound and objective scientific practices, are peer 

reviewed, and adhere to standards of quality based on objectivity, utility, and integrity. 

Comment (1-69): 

Several commenters (2972.1, 3136.1, 3307.1, 3679.1, 3747.1, 3748.1, and 3764.1) argue that EPA failed 

to evaluate and incorporate climate science studies more recent than those employed by IPCC and CCSP. 

 

Response (1-69): 

The commenters’ assertion is incorrect. 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 Section 

1.1 of this Volume for our responses to comment regarding our treatment of new and additional scientific 

literature provided through the public comment 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. 

Comment (1-70): 

Several commenters (3187.1, 3332.1, 3372.1, 3394.1, 3415.1, 3509.1, 3577.1, and 3747.1) argue that 

EPA did not to utilize an independent and objective peer review process and therefore failed to adhere to 

information quality guidelines under the IQA. Commenters argue that using federal experts involved with 

the development of IPCC, USGCRP, CCSP, and NRC reports to review the TSD was inappropriate 

because they do not represent an objective, independent perspective. One commenter argues that EPA did 

not describe how the federal experts were chosen and why this process was appropriate. 

Response (1-70): 

Please refer to Section 1.1 of this volume for EPA’s response to comments regarding the review of the 

TSD, including the role of the federal expert review and why these reviewers were chosen. The ‘Peer 

Review Policy’ section (4.2) of the Guidelines for Ensuring and Maximizing the Quality, Objectivity, 

Utility and Integrity of Information Disseminated by the Environmental Protection Agency states: 

EPA's Peer Review Policy provides that major scientifically and technically based work 

products (including scientific, engineering, economic, or statistical documents) related to 

Agency decisions should be peer-reviewed. Agency managers within Headquarters, 

Regions, laboratories, and field offices determine and are accountable for the decision 

whether to employ peer review in particular instances and, if so, its character, scope, and 

timing. These decisions are made consistent with program goals and priorities, resource 

constraints, and statutory or court-ordered deadlines. For those work products that are 

intended to support the most important decisions or that have special importance in their 

own right, external peer review is the procedure of choice. 

Given our approach to the scientific literature (described in Section III.A of the Findings), the purpose of 

the federal expert review was to ensure that the TSD accurately summarized the conclusions and 

associated uncertainties from the assessment reports. This peer-review approach for the TSD is consistent 

with EPA’s Guidelines because: 1) the reviewers 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, 2) 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, 3) the federal 

experts offered unbiased and objective review because they were external and therefore not involved with 

59 
the development of the TSD7

, and 4) the TSD clearly identifies the Federal expert reviewers (as it did in 

the version of the TSD for the Proposed Findings), which ensures transparency. 

Comment (1-71): 

Several commenters (3187.4, 3307.1, 3372.1, 3729.1, and 3764.1) argue that EPA dismissed significant 

comments, criticisms, or suggested data/studies received through the ANPR without demonstrating why 

they were not considered. 

Response (1-71): 

Please see Section 1.1 of this volume for response to comments on how EPA reviewed and considered 

public comments submitted on the ANPR. 

Comment (1-72): 

Two commenters (3136.1 and 3446.2) argue that the USGCRP's assessment report “Global Climate 

Change Impacts in the United States” does not comply with the IQA. A commenter (3347.1) argues that 

EPA failed to describe how the CCSP ensured that the 21 synthesis and assessment products, rather than 

the documents on which it relied, satisfied EPA's IQA guidelines. 

Response (1-72): 

Please see Section 1.1 of this volume for response to comments regarding the procedures that governed 

development of the USGCRP and CCSP reports. The foundation of the USGCRP’s June 2009 assessment 

report is the set of 21 CCSP SAPs, which were designed to address key policy-relevant issues in climate 

science. All 21 SAPs met federal requirements pertaining to the IQA. Furthermore, the unified synthesis 

report was extensively reviewed and revised based on comments from experts and the public. The report 

was approved by its lead USGCRP agency, NOAA, the other USGCRP agencies, and the Committee on 

the Environment and Natural Resources on behalf of the National Science and Technology Council. The 

unified synthesis product complies with the IQA and is consistent with EPA’s information quality 

guidelines. 

Regarding the information quality procedures for the individual SAPs, the CCSP provided strict guidance 

for the development and review of the 21 SAPs. The ‘Information Quality Procedures’ section of the 

Guidance to Agency Leads Regarding the Preparation of CCSP Synthesis and Assessment Products

states: 

As a lead agency for an SAP, you will be responsible for complying with the Information 

Quality Act. Section 515 of Public Law 106-554, known as the Data Quality Act, 

required the Office of Management and Budget to promulgate guidance to agencies 

ensuring the quality, objectivity, utility, and integrity of information (including statistical 

information) disseminated by Federal agencies. OMB's government-wide guidelines, 

published as interim final on September 28, 2002 (66 F.R. 49718) and finalized on 

February 22, 2002 (67 F.R. 8452), can be found on OMB’s OIRA's Web site 

http://www.whitehouse.gov/omb/inforeg/agency_info_quality_links.html. 

To facilitate any requests that might ensue pursuant to this statute, it is a good idea that you 

advise each of your authors to: 

 

7

 We note that 11 of the 12 federal expert reviewers do not work at EPA. The one EPA reviewer was not involved in 

the development of the TSD and therefore was an objective, unbiased reviewer. 

60 
a. Retain a copy of any document they cite; 

b. Identify specific pages in the literature they cite, where appropriate; and 

c. Use explanatory footnotes when the text extends beyond a fact cited in the 

literature. 

Each product team should also be prepared to make available any data it uses in the 

report’s charts or figures. These data should be publicly available as early as the expert 

review and public comment phases and should remain available thereafter. 

The National Science and Technology Council, a Cabinet-level council that coordinates science and 

technology research across the federal government, reviewed and approved each report, including the 

steps taken by the lead agency to ensure that its information quality guidelines were followed. Further 

information clearance, review, and data quality procedures for the CCSP SAPs can be found in Appendix 

B. This process was robust, objective, transparent, and complete and ensured that the USGCRP and CCSP 

reports summarized in the TSD were consistent with the IQA Guidelines. 

Comment (1-73): 

Several commenters (3509.1, 3577.1, 3596.1, 3747.1, 3748.1, 3764.1, 3769.1, and 11358.1) argue that 

EPA did not discuss or reference scientific studies that do not support the Agency's conclusion that GHG 

emissions endanger human health and welfare. 

Response (1-73): 

Please see Section 1.1 of this volume for responses to comments regarding EPA’s consideration of studies 

and information, including those which offered alternative views to the findings of the assessment 

literature. 

Comment (1-74): 

Two commenters (3397 and 3415.1) suggest that EPA ensure that it complies with the IQA and similar 

EPA guidelines in future actions regarding climate change policy. 

Response (1-74): 

As noted above, EPA has complied with the IQA by issuing guidelines that ensure and maximize the 

quality, objectivity, utility, and integrity of the information the Agency disseminates. In developing the 

Proposal, the TSD, and this Action, EPA developed and prepared the information in a manner that is 

consistent with EPA's Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility and 

Integrity of Information Disseminated by the Environmental Protection Agency. EPA intends to continue 

to act consistently with the IQA and its guidelines in future actions. 

Comment (1-75): 

Two commenters (3347.1 and 3764.1) suggest that in issuing a final finding, EPA employ information 

and data quality standards pursuant to those under the Safe Drinking Water Act (SDWA). 

Response (1-75): 

Unlike the IQA, the 1996 Amendments to the SDWA8

 added specific information requirements for 

decisions under SDWA based on science that is used to establish federal drinking water standards for 

 

8

 Safe Drinking Water Act Amendments of 1996, 42 U.S.C. 300g-1(b)(3)(A) & (B). 

61 
public water systems. The information quality standards of the SWDA Amendments were adapted into 

EPA’s Guidelines for Ensuring and Maximizing the Quality, Objectivity, Utility and Integrity of 

Information Disseminated by the Environmental Protection Agency. The SDWA obligations do not apply 

to this action. However, EPA has acted consistently with its information quality guidelines. Section 6.4 of 

EPA’s Guidelines states that: 

In our dissemination of influential scientific information regarding human health, safety

or environmentalrisk assessments, EPA will ensure, to the extent practicable and 

consistent with Agency statutes and existing legislative regulations, the objectivity of 

such information disseminated by the Agency by applying the following adaptation of the 

quality principles found in the Safe Drinking Water Act(SDWA) Amendments of 1996: 

(A) The substance of the information is accurate, reliable and unbiased. This involves the 

use of: 

(i) The best available science and supporting studies conducted in accordance with 

sound and objective scientific practices, including, when available, peer reviewed 

science and supporting studies; and 

(ii) Data collected by accepted methods or best available methods (if the reliability of 

the method and the nature of the decision justifies the use of the data). 

(B) The presentation of information on human health, safety, or environmental risks, 

consistent with the purpose of the information, is comprehensive, informative, and 

understandable. In a document made available to the public, EPA specifies: 

(i) Each population addressed by any estimate of applicable human health risk or 

each risk assessment endpoint, including populations if applicable, addressed by 

any estimate of applicable ecological risk; 

(ii) The expected risk or central estimate of human health risk for the specific 

populations affected or the ecological assessment endpoints, including 

populations if applicable; 

(iii) Each appropriate upper-bound or lower-bound estimate of risk; 

(iv) Each significant uncertainty identified in the process of the assessment of risk 

and studies that would assist in resolving the uncertainty; and 

(v) Peer-reviewed studies known to the Administrator that support, are directly 

relevant to, or fail to support any estimate of risk and the methodology used to 

reconcile inconsistencies in the scientific data. 

EPA followed has followed its information quality guidelines in developing the Findings. We relied on 

the best available peer-reviewed science, supporting studies conducted in accordance with sound and 

objective scientific practices, and data collected by accepted or best available methods. The Agency also 

has presented the information in a manner that is comprehensive, informative, and understandable. 

62 
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Appendix A

IPCC Principles and Procedures

1) Principles Governing IPCC Work

2) Procedures for the Preparation, Review, Acceptance, Adoption, Approval, and

Publication of IPCC Reports

3) Guidance Notes for Lead Authors of the IPCC Fourth Assessment Report on

Addressing Uncertainties

67

69

84

66
PRINCIPLES GOVERNING IPCC WORK

Approved at the Fourteenth Session (Vienna, 1-3 October 1998) on 1 October 1998, amended at the 21st

Session (Vienna, 3 and 6-7 November 2003) and at the 25th Session (Mauritius, 26-28 April 2006) 

_________________________________________________________________________________

INTRODUCTION

 

1. The Intergovernmental Panel on Climate Change (hereinafter referred to as the IPCC or,

synonymously, the Panel) shall concentrate its activities on the tasks allotted to it by the relevant WMO 

Executive Council and UNEP Governing Council resolutions and decisions as well as on actions in 

support of the UN Framework Convention on Climate Change process.

ROLE 

2. The role of the IPCC is to assess on a comprehensive, objective, open and transparent basis the 

scientific, technical and socio-economic information relevant to understanding the scientific basis of 

risk of human-induced climate change, its potential impacts and options for adaptation and mitigation. 

IPCC reports should be neutral with respect to policy, although they may need to deal objectively with 

scientific, technical and socio-economic factors relevant to the application of particular policies.

3. Review is an essential part of the IPCC process. Since the IPCC is an intergovernmental body, 

review of IPCC documents should involve both peer review by experts and review by governments.

ORGANIZATION

4. Major decisions of the IPCC will be taken by the Panel in plenary meetings.

5. The IPCC Bureau, the IPCC Working Group Bureaux and the Bureaux of any Task Forces of 

the IPCC shall reflect balanced geographic representation with due consideration for scientific and 

technical requirements.

6. IPCC Working Groups and any Task Forces constituted by the IPCC shall have clearly defined 

and approved mandates and work plans as established by the Panel, and shall be open-ended.

PARTICIPATION

7. Participation in the work of the IPCC is open to all UNEP and WMO Member countries.

8. Invitations to participate in the sessions of the Panel and its Working Groups, Task Forces and 

IPCC workshops shall be extended to Governments and other bodies by the Chairman of the IPCC.

9. Experts from WMO/UNEP Member countries or international, intergovernmental or nongovernmental organisations may be invited in their own right to contribute to the work of the IPCC 

Working Groups and Task Forces. Governments should be informed in advance of invitations extended 

to experts from their countries and they may nominate additional experts.

67
PROCEDURES

10. In taking decisions, and approving, adopting and accepting reports, the Panel, its Working 

Groups and any Task Forces shall use all best endeavours to reach consensus. If consensus is judged by 

the relevant body not possible: (a) for decisions on procedural issues, these shall be decided according 

to the General Regulations of the WMO; (b) for approval, adoption and acceptance of reports, differing 

views shall be explained and, upon request, recorded. Differing views on matters of a scientific,

technical or socio-economic nature shall, as appropriate in the context, be represented in the scientific, 

technical or socio-economic document concerned. Differences of views on matters of policy or

procedure shall, as appropriate in the context, be recorded in the Report of the Session. 

11. Conclusions drawn by IPCC Working Groups and any Task Forces are not official IPCC views 

until they have been accepted by the Panel in a plenary meeting.

12. Invitations to participate in the sessions of the Panel and its Working Groups, Task Forces and 

IPCC workshops should be extended at least six weeks in advance of the opening of the session.

13. Major reports, including Assessment Reports, Special Reports and Methodology Reports, basic 

documentation and other available reports for consideration at the sessions of the Panel and its Working 

Groups shall normally be made available by the IPCC Secretariat at least four weeks in advance of the 

session and, to the extent possible, in all official UN languages. 

14. Interpretation into all official UN languages shall be provided for all sessions of the IPCC

meeting in plenary, of its Bureau and its Working Groups.

15. The scheduling of the sessions of the Panel and its Working Groups and Task Forces shall be 

co-ordinated, to the extent possible, with other related international meetings.

16. These Principles shall be reviewed at least every five years and amended as appropriate. 

17. Procedures for the preparation, review, acceptance, approval, adoption and publication of IPCC 

reports are given in Appendix A.

18. Financial procedures for the IPCC are given in Appendix B.

19. Rules and Procedures for the Election of the IPCC Bureau and Any Task Force Bureau are 

given in Appendix C.

68
PROCEDURES FOR THE PREPARATION, REVIEW, ACCEPTANCE, ADOPTION,

APPROVAL AND PUBLICATION OF IPCC REPORTS

Adopted at the Fifteenth Session (San Jose, 15-18 April 1999) amended at the Twentieth Session 

(Paris, 19-21 February 2003) and Twenty-first Session (Vienna, 3 and 6-7 November 2003)

CONTENTS

1. INTRODUCTION

2. DEFINITIONS

3. IPCC MATERIAL

4. ASSESSMENT REPORTS, SYNTHESIS REPORTS, SPECIAL REPORTS AND METHODOLOGY 

REPORTS

4.1 Introduction to Review Process

4.2 Reports Accepted by Working Groups and Reports prepared by the Task Force on National Greenhouse 

Gas Inventories

4.2.1 Compilation of Lists of Coordinating Lead Authors, Lead Authors, Contributing Authors, Expert 

Reviewers, Review Editors and Government Focal Points

4.2.2 Selection of Lead Authors

4.2.3 Preparation of Draft Report

4.2.4 Review

4.2.4.1 First Review (by Experts)

4.2.4.2 Second Review (by Governments and Experts)

4.2.5 Preparation of Final Draft Report

4.3 Approval and Acceptance of Summaries for Policymakers and Adoption of Overview Chapters of 

Methodology Reports 

4.4 Reports Approved and/or Adopted by the Panel

4.4.1 The Synthesis Report

5. TECHNICAL PAPERS

6. IPCC SUPPORTING MATERIAL

6.1 Workshops and Expert Meetings

6.2 Co-sponsored Workshops and Expert Meetings

ANNEX 1 TASKS AND RESPONSIBILITIES FOR LEAD AUTHORS, COORDINATING LEAD AUTHORS, 

CONTRIBUTING AUTHORS, EXPERT REVIEWERS AND REVIEW EDITORS OF IPCC REPORTS AND 

GOVERNMENT FOCAL POINTS

ANNEX 2 PROCEDURES FOR USING NON-PUBLISHED/NON-PEER-REVIEWED SOURCES IN IPCC 

REPORTS

69
1. INTRODUCTION

This provisionally revised Appendix to the Principles Governing IPCC Work contains the 

procedures for the preparation, review, acceptance, adoption, approval and publication of IPCC 

reports and other materials relevant to methodologies. This Appendix complements the Procedures 

for the Preparation, Review, Acceptance, Adoption, Approval and Publication of IPCC Reports, 

which was adopted at the Fifteenth Session of the IPCC (San Jose, 15-18 April 1999). 

2. DEFINITIONS

The definitions of terms used in this document are as follows:

“acceptance” of IPCC Reports at a Session of the Working Group or Panel signifies that the material has not 

been subject to line by line discussion and agreement, but nevertheless presents a comprehensive, objective and 

balanced view of the subject matter.

“adoption” of IPCC Reports is a process of endorsement section by section (and not line by line) used for the 

longer report of the Synthesis Report as described in section 4.3 and for Overview Chapters of Methodology 

Reports 

“approval” of IPCC Summaries for Policymakers signifies that the material has been subjected to detailed, line 

by line discussion and agreement.

“Assessment Reports” are published materials composed of the full scientific and technical assessment of 

climate change, generally in three volumes, one for each of the Working Groups of the IPCC. Each of the 

volumes may be composed of two or more sections including: (a) a Summary for Policymakers (b) an optional 

technical summary and (c) individual chapters and their executive summaries.

“Members of the IPCC” are countries who are Members of WMO and/or UNEP.

“Methodology Reports” are published materials, which provide practical guidelines for the preparation of 

greenhouse gas inventories. Such reports may be composed of two or more sections including: (a) an Overview 

Chapter, which broadly describes the background, structure and major features of the report, (b) individual 

chapters and (c) technical Annexes. “Reports” refer to the main IPCC materials (including Assessments,

Synthesis, Methodology and Special Reports and their Summaries for Policy Makers and Overview Chapters).

“Session of a Working Group” refers to a series of meetings at the plenary level of the governmental 

representatives to a Working Group of the IPCC.

“Session of the Bureau” refers to a series of meetings of the elected members of the IPCC Bureau who may be 

accompanied by a representative of their government.

“Task Force Bureau” refers to the elected members of the Bureau of the Task Force on National Greenhouse 

Gas Inventories. It is chaired by two Co-chairs, referred to in the following as Task Force Bureau Co-chairs . 

“Session of the Panel” refers to a series of meetings at the plenary level of the governmental representatives to 

the IPCC.

“Special Report” is an assessment of a specific issue and generally follows the same structure as a volume of an 

Assessment Report.

“Summary for Policymakers” is a component of a Report, such as an Assessment, Special or Synthesis Report, 

which provides a policy-relevant but policy-neutral summary of that Report.

“Supporting Material” consists of published material, workshop proceedings and material from expert meetings 

which are either commissioned or supported by the IPCC. Supporting material may include software or

databases to facilitate the use of the IPCC Methodology Reports.

“Synthesis Reports” synthesise and integrate materials contained within the Assessment Reports and Special 

Reports and are written in a non-technical style suitable for policymakers and address a broad-range of policyrelevant but policy-neutral questions. They are composed of two sections as follows: (a) a Summary for

Policymakers and (b) a longer report.

“Technical Papers” are based on the material already in the Assessment Reports and Special Reports and are 

prepared on topics for which an objective international scientific/technical perspective is deemed essential.

70
3. IPCC MATERIAL

There are three main classes of IPCC materials, each of which is defined in Section 2.

A. IPCC Reports (which include Assessments, Synthesis and Special Reports and their Summaries for

Policymakers and Methodology Reports)

B. Technical Papers

C. Supporting Materials

The different classes of material are subject as appropriate to different levels of formal endorsement. These 

levels are described in terms of acceptance, adoption and approval as defined in Section 2.

The different levels of endorsement for the different classes of IPCC material are as follows:

A. In general, IPCC Reports are accepted by the appropriate Working Group. Reports prepared by the Task 

Force on National Greenhouse Gas Inventories are accepted by the Panel. Summaries for Policymakers are 

approved by the appropriate Working Groups. (Section 4.2) and subsequently accepted by the Panel (Section 

4.3). Overview chapters of Methodology Reports are adopted, section by section, by the appropriate 

Working Group or in case of reports prepared by the Task Force on National Greenhouse Gas Inventories by 

the Panel. In the case of the Synthesis Report the Panel adopts the underlying Report, section by section, 

and approves the Summary for Policymakers. The definition of the terms “acceptance”, “adoption” and 

"approval" will be included in the IPCC published Reports (Section 4.4).

B. Technical Papers are not accepted, approved or adopted by the Working Groups or the Panel but are finalised in 

consultation with the Bureau (Section 5)

C. Supporting Materials are not accepted, approved or adopted (Section 6).

4. ASSESSMENT REPORTS, SYNTHESIS REPORTS, SPECIAL REPORTS AND

METHODOLOGY REPORTS

4.1 Introduction to Review Process

The review process generally takes place in three stages: expert review of IPCC Reports, government/expert 

review of IPCC Reports, government review of the Summaries for Policymakers, Overview Chapters and/or the 

Synthesis Report. Working Group/Task Force Bureau Co-Chairs should aim to avoid (or at least minimise) the 

overlap of government review periods for different IPCC Reports and with Sessions of the Conference of Parties 

of the United Nations Framework Convention of Climate Change and its subsidiary bodies.

Expert review should normally be eight weeks, but not less than six weeks, except to the extent decided by the 

Panel. Government and government/expert reviews should not be less than eight weeks, except to the extent 

decided by the Panel. 

All written expert, and government review comments will be made available to reviewers on request during the 

review process and will be retained in an open archive in a location determined by the IPCC Secretariat on 

completion of the Report for a period of at least five years.

4.2 Reports Accepted by Working Groups and Reports prepared by the Task Force on National 

Greenhouse Gas Inventories

Reports presented for acceptance at Sessions of the Working Groups, or in case of reports prepared by the Task 

Force on National Greenhouse Gas Inventories reports presented for acceptance by the Panel, are the full 

scientific, technical and socio-economic Assessment Reports of the Working Groups, Special Reports and

71
Methodology Reports, that is, the IPCC Guidelines for National Greenhouse Gas Inventories or the IPCC 

Technical Guidelines for Assessing Climate Change Impacts and Adaptations.

The subject matter of these Reports shall conform to the terms of reference of the relevant Working Groups, or 

the Task Force on National Greenhouse Gas Inventories and to the work plan approved by the Panel. 

Reports to be accepted by the Working Groups, and reports prepared by the Task Force on National Greenhouse 

Gas Inventories will undergo expert and government/expert reviews. The purpose of these reviews is to ensure 

that the Reports present a comprehensive, objective, and balanced view of the areas they cover. While the large 

volume and technical detail of this material places practical limitations upon the extent to which changes to these 

Reports will normally be made at Sessions of Working Groups or the Panel, "acceptance" signifies the view of 

the Working Group or the Panel that this purpose has been achieved. The content of the authored chapters is the 

responsibility of the Lead Authors, subject to Working Group or Panel acceptance. Changes (other than

grammatical or minor editorial changes) made after acceptance by the Working Group or the Panel shall be those 

necessary to ensure consistency with the Summary for Policymakers or the Overview Chapter. These changes 

shall be identified by the Lead Authors in writing and made available to the Panel at the time it is asked to accept 

the Summary for Policymakers, in case of reports prepared by the Task Force on National Greenhouse Gas 

Inventories by the end of the session of the Panel which adopts/accepts the report. 

Reports accepted by Working Groups, or prepared by the Task Force on National Greenhouse Gas Inventories

should be formally and prominently described on the front and other introductory covers as:

"A report accepted by Working Group X of the IPCC [-OR – A report prepared by the Task Force on 

National Greenhouse Gas Inventories of the IPCC and accepted by the Panel] but not approved in 

detail." 

It is essential that Working Group and Task Force on National Greenhouse Gas Inventories work programmes 

allow enough time in their schedules, according to procedures, for a full review by experts and governments and 

for the acceptance of the report. The Working Group/Task Force Bureau Co-Chairs are responsible for 

implementing the work programme and ensuring that proper review of the material occurs in a timely manner.

To ensure proper preparation and review, the following steps should be undertaken:

1. Compilation of lists of Coordinating Lead Authors, Lead Authors, Contributing Authors, Expert Reviewers, Review 

Editors and Government Focal Points.

2. Selection of Lead Authors.

3. Preparation of draft Report.

4. Review.

a. First review (by experts).

b. Second review (by governments and experts).

5. Preparation of final draft Report.

6. Acceptance of Report at a Session of the Working Group(s) or the Panel respectively.

4.2.1 Compilation of Lists of Coordinating Lead Authors, Lead Authors, Contributing Authors, Expert 

Reviewers, Review Editors and Government Focal Points

At the request of Working Group/Task Force Bureau Co-Chairs through their respective Working Group /Task 

Force Bureau, and the IPCC Secretariat, governments, and participating organisations and the Working

Group/Task Force Bureaux should identify appropriate experts for each area in the Report who can act as 

potential Coordinating Lead Authors, Lead Authors, Contributing Authors, expert reviewers or Review Editors. 

To facilitate the identification of experts and later review by governments, governments should also designate 

their respective Focal Points. IPCC Bureau Members and Members of the Task Force Bureau should contribute 

where necessary to identifying appropriate Coordinating Lead Authors, Lead Authors, Contributing Authors, 

expert reviewers, and Review Editors in cooperation with the Government Focal Points within their region to 

72
ensure an appropriate representation of experts from developing and developed countries and countries with 

economies in transition. These should be assembled into lists available to all IPCC Members and maintained by 

the IPCC Secretariat. The tasks and responsibilities of Coordinating Lead Authors, Lead Authors, Contributing 

Authors, expert reviewers, Review Editors and government Focal Points are outlined in Annex 1.

4.2.2 Selection of Lead Authors

Coordinating Lead Authors and Lead Authors are selected by the relevant Working Group/Task Force Bureau, 

under general guidance and review provided by the Session of the Working Group or, in case of reports prepared 

by the Task Force on National Greenhouse Gas Inventories, the Panel, from those experts cited in the lists 

provided by governments and participating organisations, and other experts as appropriate, known through their 

publications and works. The composition of the group of Coordinating Lead Authors and Lead Authors for a 

section or chapter of a Report shall reflect the need to aim for a range of views, expertise and geographical 

representation (ensuring appropriate representation of experts from developing and developed countries and 

countries with economies in transition). There should be at least one and normally two or more from developing 

countries. The Coordinating Lead Authors and Lead Authors selected by the Working Group/Task Force Bureau 

may enlist other experts as Contributing Authors to assist with the work.

At the earliest opportunity, the IPCC Secretariat should inform all governments and participating organisations who the 

Coordinating Lead Authors and Lead Authors are for different chapters and indicate the general content area that the person 

will contribute to the chapter.

4.2.3 Preparation of Draft Report

Preparation of the first draft of a Report should be undertaken by Coordinating Lead Authors and Lead Authors. 

Experts who wish to contribute material for consideration in the first draft should submit it directly to the Lead 

Authors. 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, a 

hard copy should be archived and the location where such material may be accessed should be cited.

Lead Authors will work on the basis of these contributions, the peer-reviewed and internationally-available 

literature, including manuscripts that can be made available for IPCC review and selected non-peer review 

literature according to Annex 2 and IPCC Supporting Material (see section 6). Material which is not published 

but which is available to experts and reviewers may be included provided that its inclusion is fully justified in 

the context of the IPCC assessment process (see Annex 2).

In preparing the first draft, and at subsequent stages of revision after review, Lead Authors should clearly 

identify disparate views for which there is significant scientific or technical support, together with the relevant 

arguments. Technical summaries provided will be prepared under the leadership of the Working Group/Task 

Force Bureaux.

4.2.4 Review

Three principles governing the review should be borne in mind. First, the best possible scientific and technical 

advice should be included so that the IPCC Reports represent the latest scientific, technical and socio-economic 

findings and are as comprehensive as possible.

Secondly, a wide circulation process, ensuring representation of independent experts ( i.e. experts not involved 

in the preparation of that particular chapter) from developing and developed countries and countries with

economies in transition should aim to involve as many experts as possible in the IPCC process. Thirdly, the 

review process should be objective, open and transparent. 

73
To help ensure that Reports provide a balanced and complete assessment of current information, each Working 

Group/Task Force Bureau should normally select two Review Editors per chapter (including the executive 

summaries) and per technical summary of each Report.

Review Editors should normally consist of a member of the Working Group/Task Force Bureau, and an

independent expert based on the lists provided by governments and participating organisations. Review Editors 

should not be involved in the preparation or review of material for which they are an editor. In selecting Review 

Editors, the Bureaux should select from developed and developing countries and from countries with economies 

in transition, and should aim for a balanced representation of scientific, technical, and socio-economic views.

4.2.4.1 First Review (by Experts)

First draft Reports should be circulated by Working Group/Task Force Bureau Co-Chairs for review by experts 

selected by the Working Group/Task Force Bureaux and, in addition, those on the lists provided by

governments and participating organisations, noting the need to aim for a range of views, expertise, and

geographical representation. The review circulation should include:

• Experts who have significant expertise and/or publications in particular areas covered by the Report.

• Experts nominated by governments as Coordinating Lead Authors, Lead Authors, contributing authors or 

expert reviewers as included in lists maintained by the IPCC Secretariat.

• Expert reviewers nominated by appropriate organisations. 

The first draft Reports should be sent to Government Focal Points, for information, along with a list of those to whom the 

Report has been sent for review in that country.

The Working Group/Task Force Bureau Co-Chairs should make available to reviewers on request during the 

review process specific material referenced in the document being reviewed, which is not available in the 

international published literature.

Expert reviewers should provide the comments to the appropriate Lead Authors through the relevant Working 

Group/Task Force Bureau Co-Chairs with a copy, if required, to their Government Focal Point. 

Coordinating Lead Authors, in consultation with the Review Editors and in coordination with the respective 

Working Group/Task Force Bureau Co-Chairs and the IPCC Secretariat, are encouraged to supplement the draft 

revision process by organising a wider meeting with principal Contributing Authors and expert reviewers, if time 

and funding permit, in order to pay special attention to particular points of assessment or areas of major 

differences.

4.2.4.2 Second Review (by Governments and Experts)

A revised draft should be distributed by the appropriate Working Group/Task Force Bureau Co-chairs or through 

the IPCC Secretariat to governments through the designated Government Focal Points, and to all the

coordinating lead authors, lead authors and contributing authors and expert reviewers. 

Governments should send one integrated set of comments for each Report to the appropriate Working

Group/Task Force Bureau Co-chairs through their Government Focal Points.

Non-government reviewers should send their further comments to the appropriate Working Group/Task Force 

Bureau Co-Chairs with a copy to their appropriate Government Focal Point.

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4.2.5 Preparation of Final Draft Report

Preparation of a final draft Report taking into account government and expert comments for submission to a 

Session of a Working Group or, in case of a report prepared by the Task Force on National Greenhouse Gas 

Inventories, of the Panel for acceptance should be undertaken by Coordinating Lead Authors and Lead Authors 

in consultation with the Review Editors. If necessary, and timing and funding permitting, a wider meeting with 

principal Contributing Authors and expert and government reviewers is encouraged in order to pay special 

attention to particular points of assessment or areas of major differences. It is important that Reports describe 

different (possibly controversial) scientific, technical, and socio-economic views on a subject, particularly if they 

are relevant to the policy debate. The final draft should credit all Coordinating Lead Authors, Lead Authors, 

Contributing Authors, reviewers and Review Editors by name and affiliation (at the end of the Report).

4.3 Approval and Acceptance of Summaries for Policymakers and Adoption of Overview Chapters of 

Methodology Reports Related to national Greenhouse Gas Inventories 

Summary sections of Reports approved by the Working Groups and accepted by the Panel will principally be the 

Summaries for Policymakers, prepared by the respective Working Groups of their full scientific, technical and 

socio-economic assessments, and Summaries for Policymakers of Special Reports prepared by the Working 

Groups. The Summaries for Policy Makers should be subject to simultaneous review by both experts and 

governments and to a final line by line approval by a Session of the Working Group. Responsibility for 

preparing first drafts and revised drafts of Summaries for Policymakers, lies with the respective Working Group 

Co-Chairs. The Summaries for Policymakers should be prepared concurrently with the preparation of the main 

Reports.

Approval of the Summary for Policymakers at the Session of the Working Group, signifies that it is consistent 

with the factual material contained in the full scientific, technical and socioeconomic assessment or Special 

Report accepted by the Working Group. Coordinating lead authors may be asked to provide technical assistance 

in ensuring that consistency has been achieved. These Summaries for Policymakers should be formally and 

prominently described as:

"A Report of [Working Group X of] the Intergovernmental Panel on Climate Change." 

For a Summary for Policymakers approved by a Working Group to be endorsed as an IPCC Report, it must be 

accepted at a Session of the Panel. Because the Working Group approval process is open to all governments, 

Working Group approval of a Summary for Policymakers means that the Panel cannot change it. However, it is 

necessary for the Panel to review the Report at a Session, note any substantial disagreements, (in accordance 

with Principle 10 of the Principles Governing IPCC Work) and formally accept it.

Overview Chapters of Methodology Reports related to National Greenhouse Gas Inventories will be adopted 

section by section by the Panel. The Overview Chapters should be subject to simultaneous review by both 

experts and governments. Responsibility for preparing first drafts and revised drafts lies with the respective Task 

Force Bureau Co-Chairs. The Overview Chapters should be prepared concurrently with the preparation of the 

main Reports. 

4.4 Reports Approved and/or Adopted by the Panel

Reports approved and/or adopted by the Panel will be the Synthesis Report of the Assessment Reports and other 

Reports as decided by the Panel whereby Section 4.3 applies mutatis mutandis.

4.4.1 The Synthesis Report

The Synthesis Report will synthesise and integrate materials contained within the Assessment Reports and 

Special Reports and should be written in a non-technical style suitable for policymakers and address a broad 

75
range of policy-relevant but policy-neutral questions approved by the Panel. The Synthesis Report is composed 

of two sections as follows: (a) a Summary for Policymakers and (b) a longer report. The IPCC Chair will lead a 

writing team whose composition is agreed by the Bureau, noting the need to aim for a range of views, expertise 

and geographical representation. An approval and adoption procedure will allow Sessions of the Panel to

approve the SPM line by line and to ensure that the SPM and the longer report of the Synthesis Report are 

consistent, and the Synthesis Report is consistent with the underlying Assessment Reports and Special Reports 

from which the information has been synthesised and integrated. This approach will take 5-7 working days of a 

Session of the Panel.

Step 1: The longer report (30-50 pages) and the SPM (5-10 pages) of the Synthesis Report are prepared by the 

writing team.

Step 2: The longer report and the SPM of the Synthesis Report undergo simultaneous expert/government review.

Step 3: The longer report and the SPM of the Synthesis Report are then revised by Lead Authors, with the 

assistance of the Review Editors.

Step 4: The revised drafts of the longer report and the SPM of the Synthesis Report are submitted to

Governments and participating organisations eight weeks before the Session of the Panel.

Step 5: The longer report and the SPM of the Synthesis Report are both tabled for discussion in the Session of 

the Panel:

• The Session of the Panel will first provisionally approve the SPM line by line.

• The Session of the Panel will review and adopt the longer report of the Synthesis Report, section by section, 

i.e. roughly one page or less at a time. The review and adoption process for the longer report of the Synthesis 

Report should be accomplished in the following manner:

- When changes in the longer report of the Synthesis Report are required either to conform it to the 

SPM or to ensure consistency with the underlying Assessment Reports, the Panel and authors will 

note where changes are required in the longer report of the Synthesis Report to ensure consistency 

in tone and content. The authors of the longer report of the Synthesis Report will then make changes 

in the longer report of the Synthesis Report. Those Bureau members who are not authors will act as 

Review Editors to ensure that these documents are consistent and follow the directions of the 

Session of the Panel

- The longer report of the Synthesis Report is then brought back to the Session of the Panel for the 

review and adoption of the revised sections, section by section. If inconsistencies are still identified 

by the Panel, the longer report of the Synthesis Report is further refined by the Authors with the 

Assistance of the Review Editors for review and adoption by the Panel. This process is conducted 

section by section, not line by line.

• The final text of the longer report of the Synthesis Report will be adopted and the SPM approved by the 

Session of the Panel. 

The Report consisting of the longer report and the SPM of the Synthesis Report is an IPCC Report and should be formally 

and prominently described as: 

"A Report of the Intergovernmental Panel on Climate Change."

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5. TECHNICAL PAPERS

IPCC Technical Papers are prepared on topics for which an objective, international scientific/technical

perspective is deemed essential. They:

a. are based on the material already in the IPCC Assessment Reports, Special Reports or Methodology Reports;

b. are initiated: (i) in response to a formal request from the Conference of the Parties to the UN Framework 

Convention on Climate Change or its subsidiary bodies and agreed by the IPCC Bureau; or (ii) as decided by 

the Panel;

c. are prepared by a team of Lead Authors, including a Coordinating Lead Author, selected by the Working 

Group/Task Force Bureaux in accordance with the provisions of Sections 4.2.1 and 4.2.2 for the selection of 

Lead Authors and Coordinating Lead Authors.

d. are submitted in draft form for simultaneous expert and government review with circulation to expert 

reviewers and Government Focal Points in accordance with Section 4.2.4.1 at least four weeks before the 

comments are due; 

e. are revised by the Lead Authors based upon the comments received in the step above;

f. are submitted for final government review at least four weeks before the comments are due;

g. are finalised by the Lead Authors, in consultation with the IPCC Bureau which functions in the role of an 

Editorial Board, based on the comments received; and, 

h. if necessary, as determined by the IPCC Bureau, would include in a footnote differing views, based on 

comments made during final government review, not otherwise adequately reflected in the paper.

The following Guidelines should be used in interpreting requirement (a) above: The scientific, technical and 

socio-economic information in Technical Papers must be derived from:

(a) The text of IPCC Assessment Reports and Special Reports and the portions of material in cited studies that 

were relied upon in these Reports.

(b) Relevant models with their assumptions, and scenarios based on socio-economic assumptions, as they were 

used to provide information in those IPCC Reports, as well as emission profiles for sensitivity studies, if the 

basis of their construction and use is fully explained in the Technical Paper.

The Technical Papers must reflect the balance and objectivity of those Reports and support and/or explain the 

conclusions contained in those Reports. 

Information in the Technical Papers should be referenced as far as possible to the subsection of the 

relevant IPCC Reports and related material.

Such Technical Papers are then made available to the Conference of the Parties or its subsidiary bodies, in 

response to its request, and thereafter publicly. If initiated by the Panel, Technical Papers are made available 

publicly. In either case, IPCC Technical Papers prominently should state in the beginning: 

"This is a Technical Paper of the Intergovernmental Panel on Climate Change prepared in response to a 

[request from [the Conference of the Parties to]/[a subsidiary body of] the United Nations Framework 

Convention on Climate Change] / [decision of the Panel]. The material herein has undergone expert and 

government review but has not been considered by the Panel for formal acceptance or approval."

6. IPCC SUPPORTING MATERIAL

Supporting material consists of (i) published reports and proceedings from workshops and expert meetings 

within the scope of the IPCC work programme that have IPCC recognition, and (ii) material, including databases 

and software, commissioned by Working Groups, or by the Bureau of the Task Force on National Greenhouse 

Gas Inventories in support of the assessment or methodology development, process which IPCC decides should 

77
Appendix B

USGCRP/CCSP Procedures and Responsibilities

1) Guidelines for Producing CCSP Synthesis and Assessment Products

2) Clarification of Review and Clearance Process for CCSP Synthesis and

Assessment Products

3) Guidance to Agency Leads Regarding the Preparation of CCSP Synthesis and

Assessment Products

88

89

96

105
Climate Change Science Program 

Guidelines for Producing CCSP Synthesis and Assessment Products 

The CCSP Synthesis and Assessment Products 

The U.S. Climate Change Science Program (CCSP) is producing synthesis and 

assessment products to support informed discussion and decision making regarding 

climate variability and change by policy makers, resource managers, stakeholders, the 

media, and the general public. The CCSP participating agencies are coordinating their 

work to produce these reports, which will integrate research results focused on identified 

science issues and related questions frequently raised by decision makers. These reports 

will provide current evaluations of the identified science foundation that can be used for 

informing public debate, policy development, and operational decisions, and for defining 

and setting the future direction and priorities of the program. The CCSP products will be 

considered Federal government disseminations, thus they must be prepared in 

conformance with the provisions of the Data Quality Act (Section 515 of the Treasury 

and General Government Appropriations Act of 2001). Any agency sponsoring or 

contributing to the development of a product must certify that the agency’s contribution 

satisfies its Information Quality Guidelines. 

Purpose of the Guidelines 

The CCSP Strategic Plan sets forth general principles for its approach to preparing 

synthesis and assessment products: 

• Analyses structured around specific questions 

• Early and continuing involvement of stakeholders 

• Explicit treatment of uncertainties 

• Transparent public review of analysis questions, methods, and draft results 

• Adoption of a “lessons learned” approach, building on the ongoing CCSP 

analyses. 

The purpose of this document is to present guidelines that address the three steps in the 

process of preparing the synthesis and assessment products: developing the prospectus, 

drafting and revising the document, and final approval and publication of each product. 

The guidelines set forth the roles of participants and the steps in the process. The 

guidelines are intended to ensure that: 

• Independent scientific judgment serves as the guiding force in preparing the 

products so they are credible 

• Scientists, users, and other stakeholders jointly determine the scope of the 

products so the topics covered are well defined and the information provided is 

relevant to the needs expressed 

• The process of preparing the products is open at every step so the products have 

legitimacy (i.e., are perceived to have been prepared fairly). 

89
Participants and Their Roles 

CCSP Interagency Committee 

CCSP was established by the President in 2002 and integrates the U.S. Global Change 

Research Program and the Climate Change Research Initiative. The CCSP Interagency 

Committee provides executive direction for the Program, as described in Chapter 16, 

“Program Management and Review,” of the CCSP Strategic Plan. CCSP’s Interagency 

Committee is chaired by the CCSP Director (a Department of Commerce appointee) and 

includes representatives of 13 participating departments/agencies that have mission or 

funding responsibilities in climate and global change research, together with liaisons 

from the Executive Office of the President.1 Membership on the CCSP Interagency 

Committee is joint with the Subcommittee on Global Change Research (SGCR) of the 

Committee on Environment and Natural Resources (CENR) of the President’s National 

Science and Technology Council (NSTC). The CCSP Interagency Committee has overall 

responsibility for direction of the program, including compliance with the requirements 

of the Global Change Research Act of 1990. With respect to the synthesis and assessment 

products, the CCSP Interagency Committee provides oversight for the process of 

preparing the products as described in these guidelines. 

Lead Agency(ies)/Department(s) 

One or more designated CCSP agency(ies) or department(s) will take the lead in 

producing each product. The lead agency(ies) will be responsible for developing an open 

and transparent process for soliciting user input, author nomination and selection, expert 

peer review and public comment, and production/release of the products, as described in 

these guidelines. To ensure that the products incorporate as much expertise as possible, 

the lead agency(ies) will be open to the participation of other individuals or entities with 

relevant expertise and information. The entities can include other government units 

(Federal or non-Federal), Interagency Working Groups of the CCSP or other Federal 

programs, international organizations and government units, non-governmental 

organizations (NGOs), and other groups. 

 

1

 Participating departments and agencies include: Department of Agriculture (USDA), Department of 

Commerce / National Oceanic and Atmospheric Administration (DOC/NOAA), Department of Defense 

(DOD), Department of Energy (DOE), Department of Health and Human Services (HHS), Department of 

the Interior / U.S. Geological Survey (DOI/USGS), Department of State (DOS), Department of 

Transportation (DOT), Agency for International Development (USAID), Environmental Protection 

Agency (EPA), National Aeronautics and Space Administration (NASA), National Science Foundation 

(NSF), and Smithsonian Institution (SI). In addition, the Executive Office of the President and other 

related programs have designated liaisons who participate on the CCSP Interagency Committee: Office 

of Science and Technology Policy (OSTP), Council on Environmental Quality (CEQ), Office of 

Management and Budget (OMB), Climate Change Technology Program (CCTP), and Office of the 

Federal Coordinator for Meteorology (OFCM). 

90
Lead and Contributing Authors 

Lead and contributing authors of the synthesis and assessment products are scientists or 

individuals with recognized technical expertise appropriate to a product. Lead and 

contributing authors may be citizens of any country and be drawn from within or outside 

the Federal government (e.g., universities or other public or private sector organizations). 

These individuals shall be acknowledged experts, known through their publication record 

and relevant accomplishments and contributions to their field. Lead authors are 

responsible for the content of the synthesis and assessment products that are submitted to 

the CCSP Interagency Committee for review. 

Interagency Working Groups 

The CCSP Interagency Committee coordinates implementation of its activities in support 

of the Strategic Plan through Interagency Working Groups (IWGs) of program specialists 

of its participating departments and agencies, as described in Chapter 16, “Program 

Management and Review,” of the CCSP Strategic Plan. IWGs will contribute 

significantly to the preparation of the synthesis and assessment products because of their 

expertise in areas related to the products. IWGs may serve as a means for the lead 

agency(ies) to coordinate preparation of the products with supporting agencies. They may 

contribute to planning/preparing the prospectuses, scoping, drafting, reviewing, 

publishing, or disseminating the final product. 

Expert Reviewers 

Expert reviewers are scientists or individuals with other special expertise appropriate to a 

product. The expert reviewers will be selected by the lead agency(ies)/departments. As is 

the case for lead and contributing authors, reviewers may be citizens of any country and 

be drawn from within or outside the Federal government (e.g., universities or other public 

or private sector organizations). These individuals shall be known through their 

publications and other forms of recognition of their expertise. Expert reviewers will focus 

on the scientific/technical content of the draft. Employees of the lead agency(ies), lead 

authors, and other contributors to the product may not serve as expert reviewers for that 

product. The expert reviewers will be designated through a process described in the 

prospectus. 

Stakeholders 

Stakeholders are defined as they are in Chapter 11 of the CCSP Strategic Plan—that is, 

“Stakeholders are individuals or groups whose interests (financial, cultural, value-based, 

or other) are affected by climate variability, climate change, or options for adapting to or 

mitigating these phenomena.”2

 Stakeholders participate during the scoping process by 

providing information that helps define the audience and potential uses of a product. In 

addition, stakeholders provide comments on the prospectus, and on the product during the 

 

2

 See Box 11-1 (“Working Definitions”), page 112 of the CCSP Strategic Plan. 

91
public comment period. These comments are expected to focus on how well the product 

serves its intended purpose or use. 

National Research Council 

The National Academy of Sciences / National Research Council (NRC) will provide 

advice on an as-needed basis to the lead agency(ies). In the event that issues are identified 

that require further clarification, the NRC may be asked to provide additional scientific 

analyses to help bound the uncertainty associated with these issues. 

National Science and Technology Council 

The National Science and Technology Council (NSTC) will be responsible for final 

review and approval of the synthesis and assessment products. Products not cleared by 

NSTC cannot be released as disseminations of the Federal government. Consistent with 

NSTC procedures, approvals will require written concurrence from all members of the 

NSTC’s Committee on Environment and Natural Resources (CENR). All comments 

generated through the NSTC review will be addressed by the CCSP Interagency 

Committee. The CENR membership includes senior officials representing the Executive 

Office of the President and the 15 federal agencies with significant responsibilities for 

environment and natural resources programs. 

Steps of the Process 

Planning the Process and Preparing a Prospectus 

1. The lead agency(ies) solicit input from users and other stakeholders, plan preparation 

of the product, and summarize the proposed process in a draft prospectus. The draft 

prospectus will address the topics listed in the subsequent section of this document. 

2. The CCSP Interagency Committee reviews and approves the draft prospectus for 

public comment. 

3. Expert reviewers and stakeholders review the draft prospectus. The prospectus 

comment period will last at least 30 days. The draft prospectus comment period will 

be announced in a Federal Register Notice (FRN) and posted on the CCSP web site. 

4. The lead agency(ies) revise the draft prospectus and finalize author recommendations, 

taking into consideration the comments received. 

5. The CCSP Interagency Committee approves the revised prospectus and the lead 

agency(ies) notify the lead authors. 

6. The CCSP Office posts the draft prospectus comments and the final prospectus on the 

CCSP web site. 

Additional Stakeholder Interactions, if Needed 

7. Lead authors may solicit additional input from users and other stakeholders to assist 

in the development of the product. The process for soliciting this additional input will 

be open and described in the prospectus. Approaches include workshops, user 

92
surveys, telephone and email conferences, and other mechanisms. The processes used 

will reflect the expected end use of the product. The CCSP Strategic Plan identifies 

three end uses for CCSP synthesis and assessment products: 1) informing the 

evolution of the research agenda; 2) supporting adaptive management and planning; 

and 3) supporting policy formulation. The products with end uses primarily oriented 

toward the second and third categories are expected to require significant additional 

input from users to develop a clear understanding of information needs, timing of 

decisions, consideration of how uncertainty affects decision making, and other issues. 

The results from additional stakeholder interactions will be publicly available in 

summary or more extensive forms through publication on the CCSP web site. 

Drafting/Reviewing the Products 

8. Lead authors prepare the first draft, including a technical section and a summary for 

interested non-specialists. 

9. The lead agency(ies) organize and facilitate an expert peer review of the first draft 

according to process described in the prospectus. The expert peer review will precede 

the public comment period to ensure that the products are shaped by scientific 

considerations. The expert peer review process may range from that used in a 

scientific journal to a formal review panel convened by the lead agency or recognized 

external groups such as the National Research Council. Participants must be qualified 

scientific/technical experts, as demonstrated by their record of scholarly publication 

and other accomplishments. Employees of the lead agency(ies), lead authors, and 

other contributors to the product may not serve as expert reviewers for that product. 

The prospectus will describe the process for selecting expert reviewers and the 

expected dates of the review. If the expert peer review is open to all qualified experts, 

notice will be disseminated on the CCSP web site and through relevant scientific 

publications, web sites, and other means. All comments submitted during the expert 

peer review will be publicly available without attribution to the reviewer unless 

reviewers agree in advance to posting with specific attribution. 

10. Lead authors prepare the second draft of the product, taking into consideration the 

expert peer review comments. The scientific judgment of the lead authors will 

determine responses to the comments. The authors will acknowledge significant 

contributions made by expert reviewers, as applicable. 

11. The lead agency(ies) post the second draft of the product for public comment for not 

less than 45 days. Any stakeholders (plus experts who participated in the expert peer 

review process) may participate in the public comment period for the second draft. 

This includes governmental and non-governmental entities. The prospectus will 

include the expected dates of the public comment period. Notice of the public 

comment period will be disseminated on the CCSP web site, in the Federal Register, 

and through other publications, web sites, and means as appropriate to the product, to 

encourage wide public participation in the review. All comments will be publicly 

available. 

12. The lead authors will prepare a third draft of the product, taking into consideration the 

comments submitted during the public comment period. The scientific judgment of 

the lead authors will determine responses to the comments. 

93
Approving, Producing, and Releasing the Products

13. Lead agency(ies) submit the third draft of the product and a compilation of comments 

received to the CCSP Interagency Committee. 

14. If the CCSP Interagency Committee review determines that no further action is 

needed and that the product has been prepared in conformance with these guidelines 

and the Data Quality Act (including ensuring objectivity, utility, and integrity as 

defined in 67 FR 8452), they will submit the product to NSTC for approval. If the 

CCSP Interagency Committee determines that further revision is necessary, their 

comments will be sent to the lead agency(ies) for consideration and resolution by lead 

authors. 

15. If needed, NRC can be asked to provide additional scientific analysis to bound 

scientific uncertainty associated with specific issues. 

16. Once the CCSP Interagency Committee has determined that the synthesis and 

assessment report has been prepared in conformance with these guidelines and the 

Data Quality Act, the Committee will submit it to NSTC for final review and 

approval. Approval will require the concurrence of all members of the Committee on 

Environment and Natural Resources. Comments generated during the NSTC review 

will be addressed by the CCSP Interagency Committee. 

17. Once NSTC approval has been obtained and the product is finalized, the lead 

agency(ies) will produce and release the completed product using a standard format 

for all CCSP synthesis and assessment products. The final product and the comments 

received during the expert review and the public comment period will be posted, 

without attribution (unless specific reviewers agree to attribution), on the CCSP web 

site. 

18. The product will be widely disseminated through the CCSP web site and other 

mechanisms. 

Contents of the Prospectus 

The proposed process for preparing each CCSP synthesis and assessment product will be 

summarized in a prospectus that will be publicly available. The prospectus for each 

product will typically be 5-10 pages in length (plus appendices with references and 

biographical information for proposed lead authors) and will address the following 

points: 

• Overview: description of topic, audience, intended use, questions to be addressed, 

etc. 

• Contact information: email and telephone for responsible individuals at the lead 

and supporting agencies 

• Lead authors: required expertise of lead authors and biographical information for 

proposed lead authors 

• Stakeholder interactions: process already used to solicit input from users and 

other stakeholders, or proposed plans for doing so, including information for 

those interested in participating in this process 

• Drafting: materials to be used in preparing the product 

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• Review: the processes through which the product will receive expert peer review 

and public comment, including the process for selecting expert reviewers and the 

scheduled dates for the expert peer review and public comment periods 

• Related activities: description of how preparation of the product will be 

coordinated with related activities, including other national or international 

assessment processes (e.g., the Intergovernmental Panel on Climate Change) 

• Communications: proposed method of publication and dissemination of the 

product 

• Proposed timeline. 

Materials to be Used

Authors will use the published, peer-reviewed scientific literature in drafting the 

products. In the rare case that any materials used in preparing a product are not already 

published in the peer-reviewed literature, the lead agency(ies) must get approval from the 

CCSP Interagency Committee and these materials must be made available by the lead 

agency(ies) and/or CCSP Office. The use of any such non-peer-reviewed materials may 

be questioned by reviewers during the expert review or public comment period. Authors 

should seek to publish any materials used in preparing drafts of the products. 

Characteristics of the Products 

The products will identify disparate views that have significant scientific or technical 

support. They will also provide confidence levels for key findings, if this is appropriate to 

the product. 

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MEMORANDUM 

TO: CENR and CCSP Principals 

 (see Appendix, which lists these individuals) 

FROM: William Brennan, Acting Director, U.S. Climate Change Science Program 

RE: Clarification of review and clearance process for CCSP Synthesis and 

Assessment Products 

Based on “lessons learned” from moving the first few CCSP synthesis and assessment 

products through the final review and clearance stages, this memorandum provides 

clarifications to the CCSP “Guidelines for Producing Synthesis and Assessment 

Products” (<http://www.climatescience.gov/Library/sap/sap-guidelines.htm>). 

ROLE OF THE PRODUCT AUTHORS 

The lead and contributing authors are responsible for drafting the product. The 

Guidelines make a clear distinction among the respective roles of authors, expert 

reviewers, and stakeholders. Contributors may not serve as expert reviewers. All 

comments pertaining to the content of the product that arise at any stage will be referred 

to the lead author(s). These stages include the expert review, public comment period, as 

well as the final clearance stages by the lead agency, CCSP, and NSTC. Any changes that 

are proposed for the product’s contents will be reviewed by the lead author(s) to ensure 

that the scientific and technical intent is maintained. Therefore, the authors must remain 

available to address comments that arise throughout the process, including the final 

CCSP and CENR clearance stage. 

It is important that the authors adhere closely to the terms of the product described in the 

prospectus. Consistent with the principles underpinning National Research Council 

studies: “The rationale for any findings, conclusions, and recommendations should be 

fully explained in the report. This explanation might include references to the literature, 

analysis of data, or a description of the pros and cons of the range of alternatives and the 

reasons for preferring a particular option. Failure to document conclusions and 

recommendations adequately is the most common shortcoming of draft reports. 

Recommendations calling for organizational changes, adoption of new policies or 

positions, or budgetary increases within government agencies should be avoided...”1

ROLE OF THE LEAD AGENCY 

Product Review and Clearance

The CCSP “Guidelines for Producing Synthesis and Assessment Products” indicate that 

following the expert review and public comment stages, the “lead agency(ies) submit the 

 

1

 From Guidelines for the Review of National Research Council Reports, 2003.

96
third draft of the product and a compilation of comments received to the CCSP 

Interagency Committee.” Three clarifications are made below with respect to this 

statement. 

First, although there may be multiple contributing agencies to a given synthesis and 

assessment product, a single lead agency must take responsibility for ensuring 

compliance with the Information Quality Act (IQA), and if applicable, the Federal 

Advisory Committee Act (FACA). 

Second, when the lead agency transmits the product for final clearance, they should 

include a memorandum briefly indicating that “the product was prepared in compliance 

with CCSP’s Guidelines for Producing Synthesis and Assessment Products, the 

Information Quality Act (Section 515) and [LEAD AGENCY’S] corresponding IQA 

guidelines; and the Federal Advisory Committee Act [when applicable].” This 

transmittal should include the authors’ responses to the peer reviewer comments, as 

required by OMB’s Information Quality Bulletin for Peer Review, as well as descriptions 

of how the authors addressed the public comments and lead agency’s review comments. 

Third, to help expedite the clearance process, CCSP and NSTC clearance steps are 

conducted simultaneously. The lead agency will therefore simultaneously transmit the 

necessary materials to both. These materials include: the third draft of the product; the 

expert review comments and the author’s responses to them; the public comments and the 

author’s responses to them; and the aforementioned transmittal memorandum. 

To further expedite the process, the lead agency is encouraged to submit comments it has 

concerning the report’s contents during the public comment stage. The lead agency 

should not convene an expert review in addition to the one conducted as part of the report 

production process. 

The lead agency is responsible for informing the authors what their role is in each stage 

of the product development, review, public comment, and clearance process, and helping 

to ensure that the authors remain engaged through the final clearance process. 

The lead agency will inform the authors of the steps that are required to comply with the 

lead agency’s Information Quality Act guidelines as well as the Information Quality 

Bulletin for Peer Review, and ensure that the authors follow those steps. 

Use of FACA (The Federal Advisory Committee Act)

The determination of whether a FACA Committee is needed rests with the lead agency. 

When a FACA Committee is required, the lead agency is responsible for establishing the 

FACA charter and the process for appointing FACA Committee members. Note that 

there are other statutory requirements applicable to FACA Committees, such as those 

governing Federal Register announcements when a FACA Committee meets, and each 

lead agency is expected to comply with any relevant FACA guidelines. It is also 

important to note that the role of a FACA Committee is to provide advice to the lead 

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agency on the SAP; the SAP is not a product of the FACA Committee, nor is the SAP 

that is released by the Lead Agency subject to approval by a FACA Committee. 

However, any requests for changes to the product’s contents that arise in the clearance 

stage will be referred back to the lead author(s). Any changes that are proposed for the 

product’s contents will be reviewed by the lead author(s) to ensure that the scientific and 

technical intent is maintained. 

The report is prepared by the lead agency and is ultimately a product of CCSP, a 

component of the federal government. Therefore, it is essential that agencies authoring 

SAPs who choose to invoke a FACA process carefully review the FACA Committee 

advice and take whatever steps are necessary to stand behind the process used to prepare 

the report and the conclusions therein. In other words, the lead agency must "own" the 

report. 

Communications

The lead agency is responsible for developing and executing a communications plan for 

each product. Particular attention should be given to the rollout plan, which will describe 

communication plan be developed early in the product production cycle. When 

applicable, it should describe the approaches for obtaining stakeholder input during the 

production of the product, including during the public comment period. It should also 

describe how and to whom the product will be communicated following its completion. 

The plan should allow for flexibility in planning communications-related activities given 

the possibility of changing timetables. The plan should be developed in consultation with 

the lead agency’s public affairs and communications offices, and should draw from the 

“best practices” document maintained by CCSP’s Communications Interagency Working 

Group. The plan should be communicated to the Executive Office of the President (EOP) 

and the CCSP Office. 

 

ROLE OF CCSP AND NSTC 

The Global Change Research Act of 1990 requires "the Council [NSTC], through the 

Committee [CENR]" to deliver scientific assessment products to the President and 

Congress. Accordingly, the NSTC and CENR must review the assessment products prior 

to their release. Pursuant to the Act, the CCSP clearance process will occur via the 

NSTC, and will be conducted through the CENR. 

Because CCSP and NSTC clearance will be conducted simultaneously, and because some 

agencies have members on both the CCSP Principals Interagency Committee and the 

CENR, those agencies should coordinate their clearances so that each agency provides 

only one clearance. 

The CCSP/CENR clearance will rely on the lead agency's certification regarding 

compliance with CCSP's "Guidelines for Producing Synthesis and Assessment Products," 

FACA, and IQA (including the Bulletin for Peer Review). As such, an additional expert 

review is not expected. The focus of the CCSP/CENR clearance is to ensure that the 

the strategy used for the release of the report to the public. It is recommended that the 

98
policy officials with legal responsibility for the documents have reviewed and approved 

them, with particular consideration of issues such as: 

 The product does not misstate any policies or positions of the United States or any of 

its federal agencies. (The synthesis and assessment products are intended to be 

policy-relevant, not policy-prescriptive.) 

 The product clearly communicates its main message to its intended audiences and 

includes sufficient context for members of the lay public who are interested in the 

science to understand the product’s relevance. 

 The expert review and public comments were adequately addressed by the authors. 

Any requests for changes to the product’s contents that arise in the clearance stage will be 

referred back to the lead author(s). Any changes that are proposed for the product’s 

contents will be reviewed by the lead author(s) to ensure that the scientific and technical 

intent is maintained. 

PUBLIC ACCESS TO DOCUMENTS 

The following is the minimum set of documents that are posted on the web page for each 

of the synthesis and assessment products 

(http://www.climatescience.gov/Library/sap/sap-summary.php) 

• invitation for public comment on draft prospectus 

• draft prospectus 

• public comments on draft prospectus 

• final prospectus 

• peer review plan (if not part of the prospectus) 

• expert review comments on first draft report and authors’ responses to them 

• invitation for public comment on second draft report 

• second draft report 

• public comments on second draft report and authors’ responses to them 

• third draft report 

• final report 

Additional information is often posted for each product. 

EXECUTIVE SUMMARY FOR THE PRODUCTS 

Each product should include an executive summary. An effective executive summary 

contains enough information for the reader to become acquainted with the full document 

without actually reading it. It should briefly summarize: the key issue(s) being addressed 

by the product; the background and context of the issue(s); and the major conclusions. 

Recognizing that the 21 synthesis and assessment products are scientific in nature, the 

executive summary should be written for a non-expert (e.g., to the level of an informed 

99
high school graduate) and minimize the use of technical terminology and graphs and 

figures. It is recommended that the executive summary be no more than eight pages in 

length. 

It is up to the discretion of the author teams whether or not to also produce an abstract 

that succinctly distills the essence and key take-home messages of the report. 

Both the executive summary and the abstract (if included) are independent elements and 

should undergo the same review and clearance as required for the full report. 

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APPENDIX 

CENR ROSTER

George Gray 

U.S. Environmental Protection Agency Headquarters 

Conrad Lautenbacher 

National Oceanic and Atmospheric Administration 

Sharon Hays 

Office of Science and Technology Policy 

Executive Office of the President 

Michael Freilich 

National Aeronautics and Space Administration 

Jonathan Perlin 

U.S. Department of Veterans Affairs 

James Connaughton 

Council on Environmental Quality 

Vacant 

U.S. Department of Energy 

Robert Foster 

Office of the Secretary of Defense 

Mark Myers 

U.S. Geological Survey 

Department of the Interior 

Leonard Hirsch 

Smithsonian Institution 

Kathryn Jackson 

River System Operations & Environment 

Tennessee Valley Authority 

Gale Buchanan 

Research, Education, and Economics 

U.S. Department of Agriculture 

Linda Lawson 

Safety, Energy and Environment 

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Department of Transportation 

Kathie Olsen 

National Science Foundation 

Vacant 

U.S. Department of Housing & Urban Development 

David Schwartz 

U.S. Department of Health & Human Services 

David Anderson 

The Office of Management and Budget 

Executive Office of the President 

Bruce Davis 

U.S. Department of Homeland Security 

Vacant 

U.S. Department of Labor 

Claudia McMurray 

Bureau of Oceans and Int’l Environmental & Scientific Affairs 

U.S. Department of State 

Samuel Williamson 

Federal Coordinator for Meteorology 

EOP CC list

Chase Hutto 

Office of the Vice President 

Ted Wackler 

Office of Science and Technology Policy 

Executive Office of the President 

Marty Hall 

Council on Environmental Quality 

Executive Office of the President 

Other CC list

Marta Cehelsky 

Executive Secretary 

NSTC Committee on Science and 

Senior Adviser, Office of the Director 

National Science Foundation 

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CCSP roster 

William Brennan, Acting Director 

National Oceanic and Atmospheric Administration 

Department of Commerce 

Jack Kaye, Vice Chair 

HQ/Earth Sun System Division 

National Aeronautics and Space Administration 

Allen Dearry 

National Toxicology Program 

National Institute of Environmental Health Sciences 

National Institutes of Health 

Jerry Elwood 

Climate Change Research Division 

Department of Energy 

Mary Glackin 

National Oceanic and Atmospheric Administration 

Department of Commerce 

Patricia Gruber 

Office of Naval Research 

Department of Defense 

William Hohenstein 

Global Change Program Office 

U.S. Department of Agriculture 

Linda Lawson 

Safety, Energy and Environment 

Department of Transportation 

Jarvis Moyers 

Geosciences Directorate 

National Science Foundation 

Mark Myers 

U.S. Geological Survey 

Department of the Interior 

Patrick Neale 

Smithsonian Environmental Research Center. 

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Smithsonian Institution 

Jacqueline Schafer 

Bureau for Economic Growth, Agriculture, and Trade 

U.S. Agency for International Development 

Joel Scheraga 

National Center for Environmental Assessment 

U.S. Environmental Protection Agency 

Harlan Watson 

Department of State 

Executive Office and other Liaisons to the CCSP Principals Committee 

Melissa Brandt 

Office of Management and Budget 

Executive Office of the President 

Stephen Eule 

Climate Change Technology Program 

U.S. Department of Energy 

Katharine Gebbie 

National Institute of Standards & Technology 

Margaret McCalla 

Office of the Federal Coordinator for Meteorology 

George David Banks 

Council on Environmental Quality 

Executive Office of the President 

Gene Whitney 

Office of Science and Technology Policy 

Executive Office of the President 

Staff 

Peter Schultz 

Climate Change Science Program Office 

Fabien Laurier 

Climate Change Science Program Office 

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Guidance to Agency Leads Regarding the Preparation

of CCSP Synthesis and Assessment Products

1. General guidance

General guidance on preparing a Synthesis and Assessment Product (SAP) is posted on the

CCSP website. A PDF version is available by clicking on the following link:

http://www.climatescience.gov/Library/sap/sap-guidelines.pdf. CCSP has formed a work group

to assist in the preparation of the SAP’s. This work group, known as the Synthesis and

Assessment Product Advisory Group (SAPAG), has representatives from every agency that is

leading in the development of an SAP 1. The purpose of this communication is to provide

additional information and clarification on the production of the SAP’s.

2. Instructions on the length of an executive summary

Each SAP is to include an abstract and an executive summary. An effective executive

summary contains enough information for the readers to become acquainted with the full

document without actually reading it. Usually, it contains a statement of the problem, some

background information, the context of the study and the major conclusions. Recognizing that

the 21 SAP’s are scientific in nature, the executive summary should be written to the level of a

high school graduate and minimize the use of technical jargon and complicated graphs and

figures. We are recommending that the executive summary be no more than eight pages in

length. Both the executive summary and the abstract are independent elements.

With the possible exception of the conclusion and recommendation, the executive summary is

the most important part of a report. As such, it should be the best-written and most polished piece

of the document. This is because many readers may only look at the executive summary when

deciding whether or not to read the entire document. Since the executive summary is a

condensation, when creating it, you should omit any preliminaries, details, and illustrative

examples. You would include the main ideas, the facts, the necessary background to understand

the problem, and the major conclusions. Brevity and conciseness are the keys to a well-written

summary.

Do not take a few sentences from key sections of the document and string them together.

Rather, go over the entire document and make notes of the elements you consider important.

From your notes, create a rough draft of the summary. Then, polish what you have written until it

is smooth and seamless without unnecessary wordiness. Finally, ensure that your executive

summary is accurate and representative of your full document. It should not be misleading, but it

should give readers the same impression as if they had read the entire report. The Executive

Summary is to be produced by the author team and would undergo the same review and clearance

procedures required of the overall body of the SAP.

The Communications IWG has volunteered to help you with this process. Please contact the

CIWG if you would like their assistance in producing the Executive Summary or providing an

independent check on its readability. The Co-Chairs are Kent Laborde, NOAA

(kent.laborde@noaa.gov) and Jason Samenow, EPA (samenow.jason@epa.gov), and the CIWG

coordinator is Nick Sundt, CCSPO (nsundt@usgcrp.gov).

3. Peer Review

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As the agency lead for a Synthesis and Assessment Product you are responsible for

conducting a formal peer review of the report. You must follow your agency’s guidelines for

peer review that are consistent with OMB’s Final Information Quality Bulletin for Peer Review

(http://www.whitehouse.gov/omb/inforeg/peer2004/peer_bulletin.pdf). This Bulletin establishes

minimum standards for peer review and was issued under the Information Quality Act and the

OMB’s general authorities to oversee the quality of agency information, analyses, and regulatory

actions. All of the 21 SAP’s are determined to be “Highly Influential Scientific Assessments”

and the OMB Bulletin details specific procedures and requirements for conducting peer review

including the desire to conduct the peer review as a panel rather than a letter review, the timing of

the review, the scope, the selection of reviewers (expertise and balance, conflicts, independence),

public participation and disposition of comments. Note that this OMB bulletin calls for a peer

review plan for your assigned SAP. These peer review plans may be included in your prospectus,

but it must also be posted on your agency’s website, pursuant to the Information Quality Peer

Review Bulletin. Although the CCSP will be posting the prospectuses and final reports, the

posting of peer review plans is left up to each agency.

If you choose to post an intermediate draft of the SAP on your own agency’s website, please be

sure and include the following disclaimer as required by the OMB bulletin:

THIS INFORMATION IS DISTRIBUTED SOLELY FOR THE PURPOSE OF PREDISSEMINATION PEER REVIEW UNDER APPLICABLE INFORMATION QUALITY

GUIDELINES. IT HAS NOT BEEN FORMALLY DISSEMINATED BY [List your agency here].

IT DOES NOT REPRESENT AND SHOULD NOT BE CONSTRUED TO REPRESENT ANY

AGENCY DETERMINATION OR POLICY

In these instances, CCSP will not be posting a pre-dissemination draft of the SAP on the

CCSP website. Additional information is attached (see May 19, 2005 memo from Jim Mahoney

and Richard Moss).

4. Information Quality Procedures

As a lead agency for an SAP, you will be responsible for complying with the Information

Quality Act. Section 515 of Public Law 106-554, known as the Data Quality Act, required the

Office of Management and Budget to promulgate guidance to agencies ensuring the quality,

objectivity, utility, and integrity of information (including statistical information) disseminated by

Federal agencies. OMB's government-wide guidelines, published as interim final on September

28, 2002 (66 F.R. 49718) and finalized on February 22, 2002 (67 F.R. 8452), can be found on

OMB’s OIRA's website

http://www.whitehouse.gov/omb/inforeg/agency_info_quality_links.html.

To facilitate any requests that might ensue pursuant to this statute, it is a good idea that you

advise each of your authors to:

a. Retain a copy of any document they cite;

b. Identify specific pages in the literature they cite, where appropriate; and

c. Use explanatory footnotes when the text extends beyond a fact cited in the literature.

Each product team should also be prepared to make available any data it uses in the report’s

charts or figures. These data should be publicly available as early as the expert review and public

comment phases and should remain available thereafter.

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5. FACA (The Federal Advisory Committee Act)

The determination of whether a FACA committee is needed rests with the lead agency for the

SAP. When a FACA Committee is required, the lead agency is responsible for establishing the

FACA charter and the process for appointing FACA Committee members. Note that there are

specific requirements for Federal Register announcements when a FACA Committee meets and

each SAP lead agency is to comply with its own agency FACA rules. Originally, CCSP was

going to provide guidance on the FACA process, but we realized that such guidance would

possibly subordinate agency procedures that have already been adopted. Thus, it is up the

assigned agency to comply with FACA accordingly.

6. Progress Reporting

6.1. Introduction

In an effort to streamline the communications process among the U.S. Climate Change Science

Program (CCSP) Synthesis and Assessment Products (SAP) lead authors, the CCSP Office

(CCSPO) has developed a Web-based system for entering and tracking the status of the various

SAP products.

The SAP status tracking system was designed using a commercial Web-publishing software

package called ExpressionEngine. The two main components through which users will use this

system are the Control Panel page and the end-user Status page, both of which are passwordprotected. The Control Panel page is the administrative interface where you will enter SAP status

information. Once entered, the information will be available on the SAP Status page:

http://www.usgcrp.gov/sap/status/

Note that the software was upgraded in February 2006. These instructions are revised to reflect

changes in the program’s Administration Panel.

6.2. Logging on

To access the Control Panel page, go to:

http://blogs.usgcrp.gov/system-20050124-admindir/index.php

and enter the username and password you were provided.

There is also a link to the Control Panel page from the main SAP site:

http://www.usgcrp.gov/sap/

6.3. Editing SAP Status Entries

The Control Panel page will have a menu bar on the top with the following tabs:

PUBLISH | EDIT | MY ACCOUNT

To edit the information for a particular SAP, click on the EDIT tab. On the EDIT page, select

“Synthesis and Assessment Products (SAP) Status” from the dropdown menu at the upper left.

Beneath that dropdown box, select “Alphabetical” from the “Order” dropdown menu. Then click

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on the Search button. This will produce a complete list of the SAPs. Find the product you wish

to edit and click on the product name.

That will take you to a 3-tab editing page. The three tabs are:

PUBLISH FORM | DATE | CATEGORIES

Start with the “Publish Form” tab

A. “PUBLISH FORM” TAB

a) Entering and Selecting Information

“Title”

This will already be entered and should NOT be changed in any way, as this will change the

hyperlink to the product.

“Full Product Name”

“Status Summary”

“Immediate Concerns”

“Action Required (what and by whom)”

“Communications Activities, Stakeholder Interaction”

“Product's Public Home Page”

These fields are each set up as text boxes. Simply enter the appropriate information in the fields.

The remaining fields are set-up in the form of a dropdown menu followed by a text field and

relate to the following items:

 FACA Process Initiated

 FACA Charter completed

 Draft Prospectus Completed

 Draft Prospectus Approved by CCSP

 Draft Prospectus Publicly Reviewed

 Prospectus cleared for publication

 Prospectus published

 First draft completed

 Expert review completed

 Second draft completed

 Second draft publicly reviewed

 Third Draft Completed

 CCSP Review Completed

 Approved by NSTC

 Published on the Web

 Hardcopy published

For each item, the dropdown menu indicates whether or not the item has been completed (the

options are “Yes” and “No”) and the date on which it was completed. Where noted on the form,

please enter the date in the yyyy-mm-dd format:

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2005-12-31 (not 31 December 2005; 10 December, 2005; Dec. 31, 2005 or 12/31/05)

Click the blue and white “Quick Save” button in the green box near the upper right portion

of the PUBLISH page to save your changes.

b) HTML Formatting and Adding Links

In any of the text fields, you can apply standard HTML formatting to any text you wish, including

bold, underline, etc. You can also add hyperlinks to Web sites or e-mail addresses and even

images, should you so desire.

All of these formatting options are controlled via the html toolbar:

To embed Web link in part of the text, select the text and click the Link button on the html

toolbar and enter the corresponding URL. You will automatically be prompted to enter the title

for the hyperlink. This is the text in which the link will be embedded. By default, this will be the

text you selected. You will also be prompted to enter a “title attribute,” which is the text that will

appear when users hold their mouse pointers over the link. Again, by default, this will be text that

you selected. You can also add a Web link without first selecting text in which to embed it.

You can also add or embed e-mail addresses anywhere in text field. The process is similar to that

of adding or embedding a Web link. You can either select text (typically a person’s name or email address) in which to embed the link or simply add it from scratch. In either case, start by

clicking the Email button. You will be prompted to enter an e-mail address and a link title. If you

select text before clicking the Email button that text will be entered as the default link title. You

can also leave the link title field empty if you would like the e-mail address to be displayed at the

link title (note: if you select text but leave the link title field blank, the selected text will be

replaced with the e-mail address).

You can add an image (such as a logo) to an event entry by clicking the Image button. The image

must already reside somewhere on the Web and you will be prompted to enter the URL for the

image. It is possible to change the size at which an image is displayed, but to do so requires

manually entering the appropriate html code after the image source tag.

You can apply various html tags to text anywhere in the entry. These include bold (<b>), italics

(<i>), underline (<u>), (<bq>) and strikethrough (<strike>). To apply any of these tags, first

select the text to which you want the tag applied and click the appropriate button on the html

toolbar. The html tags will automatically be inserted around the selected text.

Don’t forget to click the blue and white “Quick Save” button in the green box near the

upper right portion of the PUBLISH page to save your changes.

B. “DATE” TAB

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Go to this tab to enter the date on which this SAP was last updated. As this date is not

automatically entered, it is important that you enter the date on which you make any changes to

an SAP product’s status information.

You can either enter the date in the text box or click on the “Date Calendar” icon to select the

date.

 If you are not planning any further changes, click on the “Update” button on the right side

of the screen. If you wish to make additional change under one of the other tabs

(CATEGORIES or PUBLISH FORM), click “Quick Save” to save your changes before

going to the another tab.

“Expiration Date”

Please ignore this field, as it does not apply to the SAP status information.

C. “CATEGORIES” TAB

As various steps of a product’s review, submission, and release are completed, progress should be

indicated by selecting all completed steps listed in the “Categories” tab. The various steps

available are:

Draft Prospectus Publicly Available

Final Prospectus Publicly Available

Peer review of First Draft Product Completed

Public review of Second Draft Product Completed

Third Draft Product Submitted to CCSP

Product Submitted to NSTC

Final Product Released

If only the first step (Draft Prospectus Publicly Available) has been completed, select only that

step. If multiple steps have been completed, hold down the Shift key and select the most recent

step. This should ensure that all completed steps are selected.

If you are not planning any further changes, click on the “Update” button on the right side

of the screen. If you wish to make additional change under one of the other tabs (DATE or

PUBLISH FORM), click “Quick Save” to save your changes before going to the another

tab.

6.4. Questions/Help

For general questions relating to the ExpressionEngine blog software, you can try searching the

online user guide. Simply click the User Guide link on the top-right corner of the window to

access the guide, which will open in a new window.

If you cannot find the answer to your question in the User Guide or if you have a specific

question relating to an event you entered, please contact Nick Sundt at nsundt@usgcrp.gov and

he will be happy to assist you.

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7. Communications

Communications is one the four overarching pillars of the Climate Change Science Program.

Developing a sound, comprehensive communications strategy for the release of each Synthesis

and Assessment Product (SAP) should be a priority for the responsible lead agencies in order to

broadly share and promote the findings of these considerable efforts.

This document offers recommendations for developing communications plans for the SAPs

as well as lessons learned from communications activities that were conducted for SAP 1.1. It is

intended for SAP lead authors and their associates.

This is a living document. As more SAPs are publicly released and new knowledge is gained

on successful communications strategies, this document will evolve. The CIWG and SAPAG

encourage individuals involved in SAP communications activities to provide feedback based on

their experiences.

7.1. Communications Plan Guiding Principles

 Communications are responsibility of Lead Agency for each product, and a critical

component of each SAP.

 Early on: Determine what needs to be done, by whom and when

o Develop calendar/timeline with specific events and dates

 Identify in prospectus detailed communications strategies including the identification of

key stakeholders

 Engage stakeholders throughout the process by developing contact lists, soliciting

feedback on drafts and convening workshops and briefings

 Consult with CIWG and SAPAG, and request guidance/assistance as necessary

 Consider embedding a communications expert in the report writing process and/or an

editor

 Keep lead agency public affairs and communications offices informed of product process

and progress from the beginning; keep Executive Office of President (EOP) informed

through CCSP

 Allow for flexibility in planning communications-related activities given the possibility

of changing timetables

7.2. Elements of Communications Plan and Recommendations

 Dissemination Materials – produce consistently presented materials in both hard copy

and electronic form (for dissemination via web and email); all dissemination materials,

other than the press release, should be approved by the author team and peer-reviewed

along with the entire report.

o Executive Summary* (see Appendix 1)

 Ideally 2-4 page summary (no longer than 8 pages) written at high school

reading level, including easy to understand figures and background,

explaining the relevance of the report.

 A communication professional and/or CIWG representative could help

produce this overview.

 Available within the SAP or as a stand-alone product

o Full report

 Develop list of stakeholders for electronic and hard copy distribution

111
o Press release

 Talking points and questions and answers

o Prepare iteratively with lead agency’s Office of Public Affairs and in

coordination with CCSPO prior to final product release

 Legislative briefing(s)

o Following the expert review and revision stage (optional)

 Work with CCSP/Lead Agency Congressional offices to prepare list of

legislative contacts

 Notify EOP via CCSP and appropriate officials at Lead Agency about

the Product and intent to notify Capitol Hill

 Offer optional briefing to Hill and schedule upon request

o Release of final report

 Notify EOP via CCSP and Lead Agency of intent to schedule Hill

briefings

 Schedule Hill briefings

 Reporters briefing

o Plan ahead—give reporters sufficient notice of briefing (about 1 week)

o Provide reporters with pre-reading: embargoed press release, executive summary

and abstract 1 day in advance of public release

 Constituent briefing

o Plan ahead of time:

 identify speakers

 determine who to invite and how to publicize

 assess venue options and location

o Convene shortly after product release date (within two weeks after release for

maximum effectiveness.)

o Keep it short and simple (should not have more than three speakers, and should

not last more than 90 minutes, dividing the time between presentations and open

Q&A). Discussion should focus on implications / relevance, rather than detailed

technical discussions.

 Evaluation Metrics

o Track and report:

 Who signed up to receive the report and who the report was distributed

to (in hard copy and electronically)

 Website downloads and related analytics

 Media coverage

7.3. Role of CIWG

 May serve as an informal consultant for any aspect of the development of S&A Product

communications plans

 Lead agencies’ CIWG members may provide useful assistance in writing/reviewing

communications products (press releases, executive summary, etc.), planning/convening

briefings and workshops, and disseminating products

 Contact CIWG Co-Chairs Kent Laborde <kent.laborde@noaa.gov> and Jason Samenow

<samenow.jason@epa.gov> for guidance/assistance

*Appendix 1: Executive Summary Guidance (from CIWG Implementation Plan through

2007)

112
Since many of the constituencies that are within the intended audience for the SAPs are not

specifically scientific, it is essential to provide a plain-language overview to accompany the

technical body of the SAP, or possibly stand alone in certain circumstances. There is great utility

in providing a non-technical explanation of findings contained within the SAP, as described in the

CCSP Strategic Plan Communications Section. The Executive Summary would be produced by

the author team and would expect the same expert review and clearance procedures required of

the overall body of the SAP. It should be no longer than eight pages, and should be written with a

non-technical reader in mind.

SAP lead author teams will prepare the Executive Summary with assistance from the CIWG,

as requested.

_________________________________________

1

 SAPAG Membership

Michael Slimak, EPA and Chair

Fabien Laurier, CCSPO

Clare Sierawski, DOT

Jerry Elwood, DOE

L. Dewayne Cecil, NASA

Tom Armstrong, USGS

Rick Rosen, NOAA

Margaret Walsh, USDA

113
8. Guidance to SAP Agency Leads on Handling Uncertainty

Synthesis and assessment of scientific findings exists at the interface of discovery and

societal need – it is an interdisciplinary, collaborative production and communication of

knowledge, not just information. A healthy synthesis and assessment process must explicitly

address uncertainty. This is necessary to solidify the credibility of the research effort underlying

the assessment, to build trust from stakeholders, clients, and users, and ultimately to produce

something relevant.

The 21 U.S. Climate Change Science Program (CCSP) Synthesis and Assessment Products

(SAPs) cover observations of past and present climate change, climate drivers, model-based

projections of future climate change, vulnerability and impacts, and decision support.

Characterizing, quantifying, and communicating uncertainty in climate change assessments

presents challenges for a variety of reasons, including multiple spatial scales from global to local;

long timescales (compared to instrumental records) and long time lags between forcings and

responses; reliance on linked systems of complex models; nonlinear interactions between

systems; lack of near-term verification of future predictions; and participation of subject experts

from multiple disciplines, each with different norms for treating uncertainty.

Recently, the Intergovernmental Panel on Climate Change (IPCC) and the CCSP have

produced a small number of guidance documents on handling uncertainty in climate change

assessments. Notably:

Moss, R. and S.H. Schneider, 2000: Uncertainties in the IPCC TAR: Recommendations to

lead authors for more consistent assessment and reporting. In: Guidance Papers on the Cross

Cutting Issues of the Third Assessment Report of the IPCC [Pachauri, R., T. Taniguchi, K.

Tanaka (eds.)], World Meteorological Organisation, Geneva, Switzerland, 33-51.

IPCC, 2004: Workshop on Describing Scientific Uncertainties in Climate Change to Support

Analysis of Risk and of Options. Working Group I Technical Support Unit, Boulder, Colorado

[Manning, M., M. Petit, D. Easterling, J. Murphy, A. Patwardhan, H.-H. Rogner, R. Swart and G.

Yohe (eds.)], May 11-13, 2004, National University of Ireland, Maynooth, Co. Kildare, Ireland,

146 pp. Available at:

http://ipcc-wg1.ucar.edu/meeting/URW/product/URW_Report_v2.pdf.

Morgan, M.G., H. Dowlatabadi, M. Henrion, D. Keith, R. Lempert, and T. Wilbanks, 2006:

Best practice approaches for characterizing, communicating and incorporating scientific

uncertainty in climate decision making. SAP 5.2 [report in draft form].

This memo distills certain key themes, lessons, and recommendations from these reports,

drawing most heavily from SAP 5.2, to provide guidance for SAP Agency Leads.

8.1. Types of Uncertainty:

Qualitatively different types of uncertainty need to be considered and addressed when

presenting scientific findings. Most literature makes a distinction between “statistical” uncertainty

and “structural” uncertainty: a number of related terms are also employed, often interchangeably.

Statistical uncertainty refers to parameters or observed values that are not known precisely.

Structural uncertainty refers to a basic lack of knowledge about processes and relationships that

114
we wish to capture: i.e., whether or not our conceptual model of the world accurately reflects

reality and the extent to which our physical/analytical/numerical models encapsulate this

understanding. The difference between the two is sometimes summarized as uncertainty resulting

from lack of information versus that resulting from ambiguity or disagreement over what is

known (or even knowable). Quantifying structural uncertainty is generally much less

straightforward and consequently generally receives less attention in the scientific literature, even

though it is arguably more important when dealing with climate change.

Sources of statistical uncertainty relevant to climate change include lack of data; inadequate

or incomplete measurement; variation arising in measurement instruments and methods;

systematic error and the subjective judgments needed to estimate its nature and magnitude; and

inherent randomness and variability of natural systems.

Sources of structural uncertainty relevant to climate change include inadequate or incomplete

measurements and data which prevent the elimination of plausible alternative hypotheses;

systematic errors which drive misleading interpretations of underlying mechanisms; inadequate

imagination and inventiveness in suggesting model structures; disagreement among different

experts about interpreting available evidence; incomplete or competing conceptual frameworks;

and ambiguous system boundaries or definitions.

8.2. Communicating Uncertainty in SAPs:

Critical information about the nature and sources of uncertainty are easily buried in imprecise

and opaque language.

It is important to recognize the basic differences between descriptions of uncertainty in terms

of “likelihood” or in terms of “level of confidence” of the science. Likelihood is the chance of a

defined occurrence or outcome, expressed in a probabilistic way. Level of confidence refers to the

degree of belief in the scientific community that available understanding, models, and analyses

are accurate, expressed by the degree of consensus in the available evidence and its interpretation.

Both are important when dealing with climate change and both must be communicated.

When expressing likelihood, there are many words used to describe different degrees of

uncertainty: “probable,” “possible,” “almost impossible,” “likely,” “unlikely,” etc. Such

qualitative language is inadequate because the same words can mean very different things to

different people, and the same words can mean very different things to the same person in

different contexts. The above-cited guidance documents strongly urge assigning subjective

numerical probabilities to such qualifiers and applying them consistently.

When dealing with the level of confidence in our scientific judgments about climate change

and its impacts, it is important to consider two attributes: the amount of evidence available to

support the judgment being made and the degree of consensus within the scientific community

about that judgment. The state of knowledge underlying any judgment can then be sorted into, for

example, four categories (as in Fig. 1.1 in SAP 5.2): well established; established but incomplete;

competing explanations; and speculative.

8.3. Key Issues Related to Scenarios and Modeling

Most of the SAPs, particularly those falling under Goals 2, 3, and 4, draw in some way from

future scenarios of socioeconomic changes, and the model projections of climate changes and

impacts driven by this forcing. In this context, a few additional reminders:

115
 Models contain a huge variety of explicit and implicit expert judgments, each to some

degree subjective.

 Uncertainty tends to increase going from global to regional to local scales. This is

because of increased inherent climate system variability at smaller scales and resolution

limitations of our observational data and modeling tools.

 “Downscaling” of coarse-resolution climate information to finer scales, for example

using statistical methods or high-resolution regional climate models, introduces

additional uncertainties.

 Uncertainty tends to increase going from a climate system change to an ecosystem or

human impact. This is because of the resolution issues mentioned above, the nonlinear

dependence of many impacts on changes in climate system variables, and the relatively

less well developed models of these impacts.

 Techniques such as ensemble prediction, Monte Carlo analysis, etc. can add probabilities

to model-based findings. These formal probabilities will only capture a portion of the

total uncertainty of the overall problem.

 Increased “convergence” (across simulations from different models) and reduced “bias”

(in the ability of models to reproduce observed past and present conditions), along with

similar metrics, are not guarantors of improved simulations of future conditions.

 Unpredictable behaviors emerge when system complexity increases and multiple

feedbacks interact (for example, when linking together multiple models or going to

higher resolution). It is particularly important not to underestimate uncertainty when

assessing the possibility of threshold effects and low-probability but high-consequence

events from current scientific understanding and modeling tools.

 It is much more difficult to handle socioeconomic and technological factors underlying

emissions scenarios, or, similarly, mitigative or adaptive capacity, deterministically, as

compared to predictions about the future physical state of the climate system. Therefore,

quantifying uncertainty associated with any particular socioeconomic scenario or

assumption about future human responses is less meaningful than defining how a set of

scenarios bounds the ranges of a few key variables and being explicit about which factors

are and are not considered, and/or only considered exogenously.

Bear in mind that our understanding of complex problems such as climate change may grow

richer without any reduction in perceived levels of uncertainty. Reduced uncertainty in some

areas may be offset by newly-revealed processes or unanticipated complications. Therefore,

efforts to identify and understand the full range of uncertainties is a role for the assessment

process that is just as critical as identifying where research has narrowed the ranges of specific

uncertainties.

8.4. Bottom Line Guidance:

CCSP is not providing prescriptive guidance for handling uncertainty in the production of the

21 SAPs. Rather, in the context of the topic of their SAP, each lead Agency is expected to address

uncertainty explicitly by drawing on the guidance summarized here and the above-cited

references. Agency leads are advised to

(1) Instruct authors to incorporate explicit discussions of uncertainty throughout their report.

There should be a clear assignment of responsibility for this within the author team.

(2) Instruct authors to familiarize themselves with the material contained in the above-cited

guidance documents.

116
(3) Instruct authors to create a checklist of sources of uncertainty, organized under the two

fundamental types, statistical and structural, and to apply this checklist when developing

the findings of their report. For each major finding, identify the most important sources

that are likely to affect the conclusions.

(4) Instruct authors to use uncertainty qualifiers precisely and consistently, with associated

subjective probabilities, when expressing likelihood.

(5) Instruct authors to express the level of confidence in the current scientific understanding

of an issue by being transparent about the amount of evidence available and the degree of

consensus in the scientific community surrounding that issue. In the face of wide

disagreement in the literature, presenting the range of views represented is often more

meaningful than attempting to enforce an artificial consensus.

Prepared by Chris Weaver, EPA’s Global Change Research Program

Washington, DC

Oct 2, 2006

117
Appendix C

NRC Report Development Procedures

1) The National Academies: Our Study Process – Ensuring Independent, Objective

Advice

2) The National Academies: Getting to Know the Committee Process

3) Report Review Committee Guidelines for Review: Consensus Reports

118

119

121

141
submission of information by outside parties; 3) reviews of

the scientific literature, and 4) the investigations of the

committee members and staff. In all cases, efforts are

made to solicit input from individuals who have been

directly involved in, or who have special knowledge of, the

problem under consideration. 

In accordance with federal law and with few exceptions,

information-gathering meetings of the committee are open

to the public, and any written materials provided to the committee by individuals who are not officials, agents, or

employees of the National Academies are maintained in a

public access file that is available for examination. 

The committee deliberates in meetings closed to the public in order to develop draft findings and recommendations

free from outside influences. The public is provided with

brief summaries of these meetings that include the list of

committee members present. All analyses and drafts of the

report remain confidential.

STAGE 4. Report Review

As a final check on the quality and objectivity of the study, 

all National Academies reports—whether products of 

studies, summaries of workshop proceedings, or other 

documents—must undergo a rigorous, independent external review by experts whose comments are provided 

anonymously to the committee members. The National

Academies recruit independent experts with a range of

views and perspectives to review and comment on the draft

report prepared by the committee. 

The review process is structured to ensure that each report

addresses its approved study charge and does not go beyond

it, that the findings are supported by the scientific evidence

and arguments presented, that the exposition and organization are effective, and that the report is impartial and objective. 

Each committee must respond to, but need not agree

with, reviewer comments in a detailed “response to review”

that is examined by one or two independent report review

“monitors” responsible for ensuring that the report review

criteria have been satisfied. After all committee members

and appropriate National Academies officials have signed

off on the final report, it is transmitted to the sponsor of the

study and is released to the public. Sponsors are not given

an opportunity to suggest changes in reports. The names

and affiliations of the report reviewers are made public

when the report is released.

STAGE 3. Committee Meetings,

Information Gathering, Deliberations,

and Drafting the Report

Study committees typically gather information through: 1)

meetings that are open to the public and that are announced

in advance through the National Academies Web site; 2) the

HOW THE PUBLIC CAN FOLLOW 

AND PROVIDE INPUT TO STUDIES

The Current Projects System was established

with a link from the National Academies homepage, www.national-academies.org, to

make it easy for members of the general 

public with interest in the subject to follow the

progress of a study and submit comments.

The system offers separate views by subject

and by project title. 

Reports of the National Academies are

available from the National Academies Press,

500 Fifth Street, NW, Washington, DC 20001 

1-800-624-6242 • www.nap.edu.

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. For

more information, see the National Academies’ Web site at

www.national-academies.org.

Other considerations. Membership in the three Academies

(NAS, NAE, IOM) and previous involvement in National

Academies studies are taken into account in committee 

selection. The inclusion of women, minorities, and young professionals are additional considerations.

Specific steps in the committee selection and approval

process are as follows:

 Staff solicit an extensive number of suggestions for

potential committee members from a wide range of

sources, then recommend a slate of nominees. 

 Nominees are reviewed and approved at several levels within the National Academies; a provisional slate is then

approved by the President of the National Academy of

Sciences, who is also the Chair of the National Research

Council. 

 The provisional committee list is posted for public 

comment in the Current Projects System on the Web 

(http://www4.national-academies.org/cp.nsf). 

 The provisional committee members complete background information and conflict of interest disclosure

forms. 

 The committee balance and conflict of interest discussion

is held at the first committee meeting. 

 Any conflicts of interest or issues of committee balance

and expertise are investigated; changes to the committee

are proposed and finalized. 

 Committee is formally approved. 

 Committee members continue to be screened for conflict

of interest throughout the life of the committee.

Ensuring Independent,

Objective Advice

OUR STUDY

PROCESS

NATIONALACADEMIES

THE

National Academy of Sciences

National Academy of Engineering

Institute of Medicine

National Research Council

119
Project

starts

when

funding is

received

Provisional

slate

approved by

NAS

President

Provisional

committee

posted 

for public

comment

via Current

Projects

System

Committee 

balance and 

expertise 

evaluated; 

any conflicts 

of interest are 

investigated

Final 

committee 

formally 

approved

Monitoring for 

potential conflicts 

of interest 

continues

STEPS TAKEN TO ENSURE

INDEPENDENCE AND OBJECTIVITY

The reports of the National Academies are viewed as being

valuable and credible because of the institution’s reputation for providing independent, objective, and non-partisan

advice with high standards of scientific and technical quality. Checks and balances are applied at every step in the

study process to protect the integrity of the reports and to

maintain public confidence in them. The study process can

be broken down into four major stages: 1) defining the

study; 2) committee selection and approval; 3) committee

meetings, information gathering, deliberations, and drafting

of the report; and 4) report review.

STAGE 1. Defining the Study

Before the committee selection process begins, National

Academies’ staff and members of their boards work with

sponsors to determine the specific set of questions to be

addressed by the study in a formal “statement of task,” as

well as the duration and cost of the study. The statement of

task defines and bounds the scope of the study, and it

serves as the basis for determining the expertise and the

balance of perspectives needed on the committee. 

The statement of task, work plan, and budget must be

approved by the Executive Committee of the National

Research Council Governing Board. This review often results

in changes to the proposed task and work plan. On occasion,

it results in turning down studies that the institution believes are

inappropriately framed or not within its purview. 

STAGE 2. Committee Selection and

Approval

Selection of appropriate committee members, individually

and collectively, is essential for the success of a study. All

committee members serve as individual experts, not as

representatives of organizations or interest groups. Each

member is expected to contribute to the project on the

basis of his or her own expertise and good judgment. A

committee is not finally approved until a thorough balance

and conflict of interest discussion is held at the first meeting, and any issues raised in that discussion or by the public are investigated and addressed. 

Careful steps are taken to convene 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. 

POINT OF VIEW IS DIFFERENT

FROM CONFLICT OF INTEREST

A point of view or bias is not necessarily a conflict

of interest. Committee members are expected to

have points of view, and the National Academies

attempt to balance these points of view in a way

deemed appropriate for the task. Committee

members are asked to consider respectfully the

viewpoints of other members, to reflect their own

views rather than be a representative of any

organization, and to base their scientific findings

and conclusions on the evidence. Each committee member has the right to issue a dissenting

opinion to the report if he or she disagrees with the

consensus of the other members.

NRC Governing

Board reviews and

approves study

scope and plan 

Committee’s

first meeting

Report is

released to

the sponsor

and the public

Committee and National

Academies sign off on

report

Full committee signs off on

draft report

Reviewers

comment 

on report 

DEFINING THE STUDY COMMITTEE SELECTION AND APPROVAL

COMMITTEE MEETINGS, INFORMATION GATHERING, DELIBERATIONS, AND DRAFTING REPORT

REPORT REVIEW→

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

STAGE 1 STAGE 2 STAGE 3 STAGE 4

F

or more than 140 years, the National Academies

have been advising the nation on issues of science,

technology, and medicine. The 1863 Congressional

charter signed by President Lincoln authorized this

non-governmental institution to honor top scientists

with membership and to serve the nation whenever called

upon. Today the National Academies—National Academy

of Sciences, National Academy of Engineering,

Institute of Medicine, and National Research Council—

continue that dual mission.

Like no other organization, the National Academies can

enlist the nation’s foremost scientists, engineers, health professionals, and other experts to address the scientific and

technical aspects of society’s most pressing problems. Each

year, more than 6,000 of these experts are selected to serve

on hundreds of study committees that are convened to

answer specific sets of questions. All serve without pay.

Federal agencies are the primary financial sponsors of the

Academies’ work. Additional studies are funded by state

agencies, foundations, other private sponsors, and the

National Academies endowment. The Academies provide

independent advice; the external sponsors have no control

over the conduct of a study once the statement of task and

budget are finalized. Study committees gather information

from many sources in public meetings but they carry out

their deliberations in private in order to avoid political, special

interest, and sponsor influence. 

Through this careful study process, the National Academies

produce 200–300 authoritative reports each year. Recent

reports cover such topics as the obesity epidemic, the use

of forensics in the courtroom, invasive plants, underage

drinking, the Hubble Telescope, vaccine safety, the hydrogen

economy, transportation safety, climate change, and homeland security. Many reports influence policy decisions; some

are instrumental in enabling new research programs; others

provide program reviews.

120

The National Academy

of Sciences was established

by Congress more than a 

century ago to provide scientific and technological

advice to the nation. Over

the years, the Academy

has evolved to incorporate

four distinguished organizations the National

Academy of Sciences, the

National Academy of

Engineering, the Institute

ABOUT THIS UNIQUE INSTITUTION 2

THE STUDY PROCESS 5

Committee Selection 6

Bias and Conflict of Interest 6

Committee Deliberations 7

Studies of Risk Assessment 8

Institutional Oversight 8

Writing the Report 9

Role of Staff 9

Report Review 10

Confidentiality 10

Public Access 12

DISSEMINATION 14

Congressional Outreach 14

Academies’ News Office 15

National Academies Press 15

Communications Initiative 16

Academies’ Web Site 16

CONTENTS

USEFUL REFERENCES 1 7

122
ACADEMIES

ASKED TO SERVE . . .

THE NATIONAL

Y

SO YOU'VE BEEN 

ou have been invited to

work on a project at the National

Academies and may be wondering

exactly what your role is as a committee member. This document is a brief

introduction to the institution and is

designed to give you a sense of the

committee process. No two projects

are alike, of course, and people’s

experiences vary. But general policies

and procedures have been developed

to ensure that the time you spend as a

volunteer in service to the nation is

productive and rewarding.

123
ACADEMIES

THE NATIONAL

2

The National Academy of Sciences was established by Congress more than a 

century ago to provide scientific and technological advice to the nation. Over the

years, the Academy has evolved to incorporate four distinguished organizations

— the National Academy of Sciences, the National Academy of Engineering, the

Institute of Medicine, and the National Research Council. Known collectively as

the National Academies, they perform an unparalleled public service by bringing

together experts in all areas of scientific and technological endeavor. These

experts serve as volunteers to address critical national issues and give unbiased

advice to the federal government and the public. Most of this advice is provided

either by the National Research Council — the chief operating arm of the

Academy of Sciences and the Academy of Engineering — or by the Institute of

Medicine, which operates under the charter of the National Academy of Sciences

and according to Research Council rules.

ABOUT THIS UNIQUE INSTITUTION

JD TALASEK

124
The National Academies provide science and technology advice in several different forms: 

written reports reflecting the consensus reached by an expert study committee; symposia and

convocations engaging large audiences in discussion of national issues; proceedings from conferences and workshops; or “white papers” on policy issues of special interest. Each project is

conducted or overseen by a committee serving pro bono, whose members are selected for

their expertise on the subject.

This booklet focuses primarily on the study committee process, in which a committee of

approximately 10 to 20 members with a diverse range of expertise and perspectives is 

convened to address a particular question or set of questions. Study committees have been

assembled, for example, to address various aspects of the AIDS crisis, to consider the use of

forensics techniques in the courts, and to offer policy advice on setting priorities for federal

funding of research and development. Before a committee meets, one of the volunteer experts

is appointed to serve as the committee chair, and a member of the Academies’ staff is

assigned as the study director.

Each committee investigates the many facets of the problem described in its statement of task

and develops a report of its findings, conclusions, and recommendations, based on the 

available scientific evidence. This report is subjected to rigorous review by a second group 

of independent experts anonymous to the committee. After revisions are made by the committee to satisfy the institution’s review process, the report is transmitted to the agency or 

organization that sponsored the study, and then released to the public. Names and affiliations

of principal reviewers are made public when the report is released.

The National Academies and their operations are distinctive in several ways:

• Committee members serve without compensation, except for reimbursement of expenses. 

• Most projects originate from requests made by outside sponsors such as Congress, 

federal agencies, and foundations. However, volunteer members of the institution’s 

boards also develop ideas for studies that subsequently are funded by external sources. 

In addition, the Academies have been building their own endowments through private 

contributions so that they can address important issues of science and policy without 

government or foundation support. 

3

125
ACADEMIES

THE NATIONAL

4

• The institution has no research laboratories. In reaching conclusions and recommendations, study committees hear invited testimony and evaluate published research from the 

relevant scientific literature, as part of an educational process designed to enable the 

committee to reach consensus. The resulting reports often present a novel synthesis of 

ideas unique to the committee; these reports are highly regarded by the sponsoring 

agencies and the public for their thorough analysis and carefully supported recommendations. The reputation of the institution for objectivity, integrity, independence, and 

competence is one of its most valuable assets. For this reason, procedures designed to 

ensure excellence apply to each study undertaken.

• The National Academies do not compete in response to federal requests for proposals. 

Their one-of-a-kind service, not duplicated by other organizations, was reaffirmed in a 

January 1993 executive order from President Bush.

• The Academies are not subject to the Federal Advisory Committee Act in the way 

government agencies are; neither are they subject to the Freedom of Information Act. 

However, the Federal Advisory Committee Act Amendments of 1997 (Public Law 

105-153) require the Academies to provide opportunities for public access and 

involvement in the study process. Those requirements are discussed in the Public Access

section of this booklet.

126
5

The core of the institution’s work consists of studies usually of six months to two

years in duration and performed under contract to a sponsor or set of sponsors.

Each study is conducted by a committee selected expressly for that purpose. The

committee meets at intervals to consider its scope of work, to review the relevant

scientific evidence, and to develop its findings, conclusions, and recommendations. Once the report has been outlined by the committee, various sections often

are written by individual members. The writing process is guided by the committee

chair and aided by the committee staff, in particular by the study director.

The charge to the committee — developed before committee members are

selected — is the formal statement of the questions to be addressed by the

study. This statement defines the study’s scope and issues to be examined. If a

committee finds in the course of its work that this description is inadequate, the

charge can be formally modified through petition to the Executive Committee of

the National Research Council’s Governing Board. Such petitions are carefully

examined; a committee that is well-balanced for one purpose may not be 

appropriately constructed for a modified task.

THE STUDY PROCESS

JD TALASEK

127
ACADEMIES

COMMITTEE SELECTION

The search for candidates for committee membership is initiated by staff with input and oversight from the relevant boards. In defining the areas of expertise that should be represented 

on a committee and identifying individuals qualified to serve, the staff reviews scholarly 

literature and consults widely with the institution’s members and volunteers, knowledgeable

authorities, and professional associations. Sponsors may offer suggestions but do not select

committee members.

Committee members are chosen on the basis of their knowledge and experience in the various

aspects of the topic to be investigated, and after careful review are appointed by the chair of

the National Research Council, who also is the president of the National Academy of 

Sciences. The names, affiliations, and short biographies of committee members are posted 

for public comment in the “Current Projects” area of the institution’s Web site at 

<national-academies.org>.

BIAS AND CONFLICT OF INTEREST 

Committee members serve as individuals, not as representatives of organizations or interest

groups. Each person is selected on the basis of his or her expertise and good judgment, and

is expected to contribute accordingly to the study.

The credibility of a report can be called into question if the committee that produced it is perceived to be biased. Potential sources of bias and conflict of interest are significant issues that

are taken into consideration in the selection of committee members and are re-examined periodically throughout the study process.

Recognizing that each individual who is knowledgeable about a subject brings his or her own

biases and experiences to any study effort, the institution has adopted specific procedures to

achieve appropriate balance in the committee membership and to avoid conflicts of interest. At

the time of appointment, each committee member is required to list all professional, consulting,

and financial connections, as well as to describe pertinent intellectual positions and public

statements by filling out a confidential form, “Background Information and Confidential Conflict

of Interest Disclosure.” The committee appointment is not finalized until the institution completes a review of information regarding potential conflicts of interest and bias.

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As part of the process of becoming acquainted with each other and with the task before them,

committee members discuss this information in closed session at the beginning of their first

meeting and annually thereafter. The information also is reviewed by officials of the institution,

and if a potential conflict becomes apparent, the committee member may be asked to resign.

In exceptional circumstances, an individual may continue to serve on the committee if the 

conflict of interest is promptly and publicly disclosed, and the National Academies have determined that the conflict is unavoidable. To fulfill its legal requirement for such public disclosure,

the institution posts on its Web site a brief statement describing the unavoidable conflict. When

a question of balance arises, the usual procedure is to add members to the committee to

achieve the appropriate balance.

COMMITTEE DELIBERATIONS

A successful report is the result of a dynamic group process, requiring that committee members be open to new ideas and innovative solutions, and be willing to learn from one another.

Committees are expected to be evenhanded and to examine all evidence dispassionately.

Although all interested parties should be heard and their views given serious and respectful

consideration, one of the committee’s primary roles is to separate fact from opinion, analysis

from advocacy. Scientific standards are essential in evaluating all arguments and alternatives.

Most committees eventually issue a unanimous report of their conclusions. Members of committees should strive for consensus, but not at the cost of substantially weakening their analyses and conclusions. It may be more valuable in the long run to explain the rationale behind

areas of disagreement than to issue unanimous conclusions that are so limited that they fail to

contribute to a better understanding of the issue.

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STUDIES OF RISK ASSESSMENT

Studies involving the assessment of risk are among the most difficult and potentially 

controversial. Government agencies and others engaged in the management of hazardous 

conditions and substances often are faced with making policy decisions in the absence 

of conclusive scientific evidence. Many Research Council and Institute of Medicine studies

dealing with risk are requested by federal agencies seeking specific answers on which to 

base important policy decisions. In studies involving incomplete or inconclusive data, the 

collective experience and reasoned judgment of committee members become crucial factors 

in developing conclusions and recommendations.

It is critical for each committee working on a study of risk assessment to distinguish clearly

between conclusions based on scientific evidence and those based on informed judgment. 

In cases in which scientific proof is incomplete, special care is needed to explain how the 

committee arrived at its conclusions. Moreover, the assumptions used should be explicitly 

identified and justified. A conscientious effort to be clear in writing the report will help to avoid

the potential for misinterpretation when the report is published.

The institution has developed guidelines for committees charged with conducting 

risk-related projects (available on the Academies’ intranet site, the AcademyNet). These guidelines emphasize the special care that must be taken in assembling the committee, orienting

new committee members, conducting bias discussions, managing the consensus process,

handling any minority opinions, and writing the report.

INSTITUTIONAL OVERSIGHT

Every study is subject to oversight, from initial approval to public release of a final report.

Whether a study is requested by a government agency or a private organization, or is initiated within the institution itself, the study proposal first must be approved by the Executive

Committee of the Research Council’s Governing Board. This group carefully examines the

proposal and considers such factors as the importance and timeliness of the question,

whether there is an adequate base of scientific knowledge to support the study, the intended audience, the likely impact of the report, and the competence of the institution to

take on the task.

Oversight is provided throughout the duration of a study by the various supervisory entities

within the Research Council and the Institute of Medicine, as well as by the committee chair

and the staff member serving as study director. Their responsibilities are to ensure that the

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committee focuses on its stated tasks, that measures of quality control are enforced, and that

the study proceeds on schedule and within budget. Sponsors do not engage in oversight of

the studies.

WRITING THE REPORT

Completing the consensus-building process and writing a report that clearly presents the committee’s findings, conclusions, and recommendations may be the most challenging, yet rewarding aspects of serving on a study committee. The report may well become an important reference for those who formulate public policy. For this reason, the value of a carefully prepared

report cannot be overstated.

Although each committee may go about the drafting of its report differently, every report is the

collective product of a group process. A committee member often will draft a chapter or portion of the report, but the “author of record” is the entire committee, and the responsibility for

authorship lies with the committee as well. Individual authorship generally is not credited; the

report and all copyrights become the property of the National Academy of Sciences.

ROLE OF STAFF

Each committee is assisted in its work by highly qualified staff members who facilitate the work of

the committee during the conduct of the study. When committee and staff form a close professional partnership, the experience can be exhilarating for everyone involved.

Staff help to create the objective atmosphere in which the committee’s deliberations take

place. In addition, staff are responsible for ensuring that institutional procedures and practices

are followed throughout the study, and that the study stays on schedule and within budget.

Staff members assist with many aspects of assembling the report, including researching, writing, integrating portions written by others, and ensuring consistent style and format. However,

the conclusions and recommendations are those of the committee. Staff do not insert their

personal conclusions or recommendations into the report.

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REPORT REVIEW 

Like all good science, reports should be based on fact and rigorous analysis. All of the institution’s reports — whether products of studies, summaries of workshop proceedings, or abbreviated documents — must undergo an independent review by anonymous experts who were not

involved in the report’s preparation. 

Report review is an integral and constructive part of the study process. It is the final opportunity

for committees to test their reasoning, conclusions, and recommendations before release of the

report to the public.

The Report Review Committee (RRC) ensures that an independent review has been 

conducted, and that:

• the report addresses the approved study charge and does not go beyond it; 

• the findings are supported by the evidence and arguments presented; 

• the exposition and organization are effective; and 

• the tone of the report is impartial, and sensitive policy issues are treated with 

appropriate care. 

The report may not be transmitted to the sponsor or released to the public until review has

been completed to the satisfaction of the Report Review Committee. Details of the quality

standards followed by reviewers can be found in the RRC document Guidelines for Review:

Consensus Reports. Once the report is released, names and affiliations of principal reviewers

are made public.

CONFIDENTIALITY

During more than a century of service, the institution has earned a reputation for providing

independent, expert advice. Procedures and practices have evolved that protect committees

from outside pressures and thereby safeguard the credibility and integrity of their work. 

Committee meetings, particularly as the committee gathers information, are usually open to

interested individuals and the news media. However, meetings are closed when the committee

is deliberating to develop its findings and during discussion of financial and personnel matters.

Closed meetings are not open to the public or to any person who is not a committee 

member or an official, agent, or employee of the Academies.

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Reports are the product of the institution, not of the committee alone. Committee deliberations,

drafts of the report in progress, and tentative conclusions all are confidential until a completed

report passes through review and receives sign-off by the Report Review Committee and by

the major unit responsible for the study. Committee members are expected to reject any

requests for early briefings or media interviews on the committee’s findings, and to treat 

committee deliberations and draft products as confidential.

A cardinal rule to keep in mind: Until the review process has been satisfactorily completed,

the document is not an official report of the National Academies. Conclusions and recommendations can change up to the final sign-off; premature briefings for sponsors or others outside

the institution may lock committees into a position not fully supported by the evidence. Early

briefings also damage the final report by subjecting the committee to the accusation that it

permitted the sponsor to preview and approve the conclusions and recommendations — a

serious charge that undermines the independence and integrity of both the committee and

the institution. In such cases, the hard work of the committee can be discredited, diminishing

the report’s value to the sponsor and to the nation.

Until the report is publicly released, committee members should limit public comment to 

the following:

• the scope of the project and what the committee has been asked to do; 

• the name of the sponsor and estimated cost of the study, if known; and 

• the makeup of the committee, including names and affiliations of 

committee members.

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ACADEMIES

This and other relevant information can be found on

the institution’s Web site at <national-academies.org>

and in its public access files. These files, which

include items such as materials presented to the

committee in data-gathering meetings open to the

public, are available for public review.

PUBLIC ACCESS

Legislation passed in late 1997 protects the

Academies from government control under the

Federal Advisory Committee Act. But in doing so, it

explicitly requires the Academies to ensure public

access to committee activities.

For example, any meeting of a committee at which

anyone other than committee members or officials,

agents, or employees of the institution is present —

whether in person, by telephone, or teleconference

— is considered a “data-gathering committee meeting.” Except as determined and approved in advance

by the Academies’ leadership, all data-gathering

committee meetings are open to the public. Datagathering meetings that involve committee consideration of classified, proprietary, or personal-privacy

information, however, exemplify situations in which

meetings are not open to the public.

To facilitate the process of informing the public about

a committee’s work and enabling interested individuals to attend open data-gathering sessions, an

advance announcement must be posted — preferably 14 days before the meeting — on the institution’s Web site.

Data-gathering committee meetings should be

regarded as on the record. Therefore, whether or not

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representatives of the news media are in attendance, the chair of the meeting should advise

everyone present of the nature and purpose of the

meeting. Statements of this type are necessary to

help ensure that participants and observers do not

misinterpret the purpose of the meeting, or prematurely interpret the discussion to be the positions of

individual participants, the committee, or the institution. For guidance on assembling introductory

remarks for the chair, see “Setting the Ground Rules

at an Open Meeting to Which the Public and Press

Have Been Invited as Observers,” available on the

AcademyNet.

To acquaint the public with the background of committee members, the chair should ask each member to state briefly, in open session at the first 

data-gathering committee meeting, those aspects

of his or her background, experience, expertise,

and previously stated positions that appear relevant

to the functions to be performed by the committee.

Committees also should create opportunities that

facilitate the gathering of as wide a range of views

as possible, such as having a session for public

comments at a data-gathering committee meeting

or soliciting comments in writing or via e-mail from

interested members of the public.

Within 10 days following a closed committee meeting, the Academies will post a brief summary of the

meeting on the Web, listing the committee members

present, the topics discussed, and materials made

available to the committee. This summary will not

disclose the substantive content, conclusions, 

recommendations, discussion of draft reports, or

any report review comments.

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Once a report has successfully completed review and been thoroughly edited, Academies

staff working with the Office of Congressional and Government Affairs and the Office of

News and Public Information develop a release timeline. At this stage it is critical to 

observe carefully the institution’s rules of confidentiality until the report is ready for release 

to the public.

CONGRESSIONAL OUTREACH

The Office of Congressional and Government Affairs (OCGA) is responsible for dissemination

and outreach to the congressional and executive branches of government. One component

of this is congressional and sponsor briefings. These briefings take place up to 24 hours

before the public release of a report. Dissemination of reports that are congressionally mandated involves specific guidelines for briefing members of Congress. For other reports, OCGA

informs concerned members of Congress and the appropriate congressional committees. 

OCGA also monitors congressional activities on issues that affect the National Academies and

helps committee members or staff prepare and submit testimony for Congress.

DISSEMINATION

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ACADEMIES’ NEWS OFFICE

The Office of News and Public Information (ONPI) is the liaison between the Academies and

the news media and general public. Many reports of the National Academies are newsworthy,

and the media serve as an important channel for disseminating the content of reports.

For each report, ONPI works closely with study staff to develop a release plan that may include

a news release; public briefing; embargo arrangement; outreach to targeted media; and media

preparation for committee members to help them speak comfortably with journalists and handle potentially difficult inquiries.

Committee members or staff who receive a call from a reporter concerning a pending report

generally should feel free to respond, but in a limited way. Journalists may be provided with a

project’s statement of task, the committee roster, the identity of the sponsor(s), and the cost of

the study, as well as general information about the background and scope of the project.

Findings and recommendations, however, must be kept confidential until the report is released. 

ONPI should be informed of substantive conversations with the news media, especially if there

is any problem. Staff or committee members seeking guidance about media relations may 

consult with ONPI at any time. If a reporter is asking leading questions or inquiring about 

controversial issues, it often is best to delay answering until after conferring with ONPI.

ONPI also publicizes Academies reports through weekly and monthly electronic newsletters

and the institution’s magazine, The National Academies In Focus.

NATIONAL ACADEMIES PRESS

The National Academies Press (NAP) is the publisher

for the institution. NAP offers a wide range of services,

including publication planning, editing, printing, marketing, and distribution. It publishes nearly 200 committee

reports each year, ranging from pre-publication photocopies to full-color, high-quality trade books that are

marketed and sold around the world. The NAP Web

site at <www.nap.edu> makes all of these publications

available online — more than 3,000 books and 500,000

book pages in 2005. Most books published by NAP are

also offered as PDF files, many of which are free 

to the public. 

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Current committee members are permitted free access to all available PDF files and should

contact study staff to make the necessary arrangements; they also receive a 25 percent 

discount on all books purchased from NAP for personal use.

COMMUNICATIONS INITIATIVE

The National Academies strive to disseminate the results of their work to a wide range of audiences. The Office of Communications was formed in 2001 to help the institution accomplish

this. Specifically, this office works in partnership with Academies program units to engage the

public with the institution’s work, create new products and services for different audiences, build

stronger relationships with existing and potential sponsors, and harness the Web as an effective

communication vehicle. Committees are encouraged to identify potential audiences for their

studies early in the process, discuss how to reach those audiences, and consider ways of

expanding public interest throughout the study process.

ACADEMIES’ WEB SITE

Information about the institution’s work is available on the Web at <national-academies.org>. 

A broad range of material can be found online, including current project information, news

releases, and full-text reports.

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The National Academy

of Sciences was established

by Congress more than a 

century ago to provide scientific and technological

advice to the nation. Over

the years, the Academy

has evolved to incorporate

four distinguished organizations the National

Academy of Sciences, the

National Academy of

Engineering, the Institute

ABOUT THIS UNIQUE INSTITUTION 2

THE STUDY PROCESS 5

Committee Selection 6

Bias and Conflict of Interest 6

Committee Deliberations 7

Studies of Risk Assessment 8

Institutional Oversight 8

Writing the Report 9

Role of Staff 9

Report Review 10

Confidentiality 10

Public Access 12

DISSEMINATION 14

Congressional Outreach 14

Academies’ News Office 15

National Academies Press 15

Communications Initiative 16

Academies’ Web Site 16

CONTENTS

USEFUL REFERENCES 1 7
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CONSENSUS 

REPORTS

RepoRt Review Committee

GUIDELINES FOR REVIEW THE

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may not be released to the sponsors or the public, nor 

may its findings be disclosed, until after the review process has been satisfactorily completed and all authors 

have approved the revised draft.

CONfIDENTIALITy AND ANONyMITy

To encourage reviewers to express their views freely, the 

review comments are treated as confidential documents 

and are given to the authors of the report with identifiers 

removed. After submitting their comments, reviewers are 

asked to return or destroy the draft manuscript and to 

refrain from disclosing their comments or the contents of 

the draft. The names and affiliations of participants in 

the review will be made public when the report is released (usually by acknowledgment in the printed report), but their comments remain confidential. Even after 

release of the report, reviewers should not divulge their 

comments or any changes made to the draft manuscript. 

These restrictions are imperative in safeguarding the integrity of the institutional review process.

SUPPORTINg EvIDENCE

The rationale for any findings, conclusions, and recommendations should be fully explained in the report. This 

explanation might include references to the literature, 

analysis of data, or a description of the pros and cons 

of the range of alternatives and the reasons for preferring a particular option. Failure to document conclusions 

and recommendations adequately is the most common 

shortcoming of draft reports. Of particular concern are 

recommendations calling for organizational changes or 

budgetary increases within government agencies or for 

additional work for the National Academies. In general, 

such recommendations should be avoided unless specifically called for in the study charge.

SUMMARIES AND ExECUTIvE SUMMARIES

Every study report must contain a Summary or an Executive Summary that clearly and concisely communicates 

the main message of the report to its intended audiences, 

including non-experts and readers who do not read the rest 

of the report. The Summary or Executive Summary may not 

distort or go beyond the content of the report. It must clearly 

identify the study charge, but need not include all conclusions and recommendations. An Executive Summary should 

typically be less than 800 words and not exceed 1,000 

words. It may appear alone or be followed by a Summary. A 

Summary should typically be less than 3,000 words and not 

exceed 5,000 words unless preceded by an Executive Summary (which may be called an “abstract” or “synopsis” when 

it precedes a Summary). 

CONSENSUS AND DISSENT

National Academies committees strive for consensus, but on 

rare occasion--despite extensive deliberations--one or more 

committee members may not concur with the views of the 

majority. Matters of disagreement should be addressed 

forthrightly in the report. As a final recourse, a committee 

member may choose to prepare a brief dissent (no more 

than 5,000 words) succinctly describing the issues of contention and the arguments in support of the minority view. This 

statement should be included as an appendix to the draft 

report, with reference to it in the introductory text and Table 

of Contents. A dissent may not address issues outside the 

study charge, misrepresent the majority’s views, or contain 

other inaccuracies. Any questions regarding the appropriateness of material included in a dissent shall be referred to 

the RRC chair. Although reviewers’ comments on the statement are given to its author for consideration, no formal 

written response is required.

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REvIEw CRITERIA

National Academies reports cover a broad range of topics 

and appear in a variety of different forms. Although no 

rigid set of criteria is likely to be applicable to all reports, 

reviewers may find the following questions useful in formulating their comments. (A separate set of criteria is used for 

“letter reports” and other abbreviated documents.)

1. Is the charge clearly described in the report? 

 Are all aspects of the charge fully ad- 

 dressed? Do the authors go beyond their 

 charge or their expertise?

2. Are the conclusions and recommendations 

 adequately supported by evidence,analysis, 

 and argument? Are uncertainties or 

 incompleteness in the evidence explicitly 

 recognized? If any recommendations are 

 based on value judgments or the collective 

 opinions of the authors, is this acknowledged and 

 are adequate reasons given for reaching those 

 judgments? If the report is based on a sworkshop, 

 are findings and conclusions attributed to either an 

 individual or an NRC committee?

3. Are the data and analyses handled competently? 

 Are statistical methods applied appropriately?

4. Are sensitive policy issues treated with proper 

 care? For example, if the report contains 

 recommendations pertaining to the reorganization 

 of an agency or the creation of a new institutional 

 entity, are the advantages and disadvantages 

 of alternative options, including the status quo, 

 considered? consistent with other sections of 

 the report?

5. Are the report’s exposition and organization 

 effective? Is the title appropriate?

6. Is the report fair? Is its tone impartial and 

 devoid of special pleading?

7. Does the executive summary concisely and 

 accurately describe the key findings and 

 recommendations? Is it consistent with other 

 sections of the report?

8. Are signed papers or appendices, if any, 

 relevant to the charge? If the report relies on 

 signed papers to support consensus findings 

 or recommendations, do the papers meet 

 criterion 3 above?

9. What other significant improvements, if any, 

 might be made in the report?

In providing comments, reviewers are encouraged to distinguish issues they consider to be of general/major concern 

from other, less significant points.

PURPOSE

The purpose of review is to assist the authors in making 

their report as accurate and effective as possible and to 

ensure that they and the National Academies are creditably represented by the report published in both their 

names. Review not only fulfills the institutional obligation to 

exercise oversight, but also provides the authors with preliminary reactions from a diverse group of experts and, as 

a result, enhances the clarity, cogency, and credibility of 

the final document. Reviewers are asked to consider 

whether in their judgment the evidence and arguments 

presented are sound and the report is fully responsive to 

the study charge, not whether they concur with the findings.

PROCESS

The report review process is overseen by the Report 

Review Committee (RRC), made up of approximately 

30 members of the National Academy of Sciences, National Academy of Engineering, and Institute of Medicine. The process is managed by the commission, 

board, or office responsible for institutional oversight of 

the project. This administrative unit, in consultation with 

the RRC, appoints a group of independent reviewers 

with diverse perspectives on key issues considered in 

the report. A draft report is sent to reviewers only after 

all authors have indicated that they are satisfied with its 

form and content. Reviewers receive the complete report (including front matter, preface, executive summary, and all appendices), along with the statement of 

task and this brochure. Reviewers are asked to provide 

written comments on any and all aspects of the draft 

report, but to pay particular attention to the review criteria set forth in the final section of this brochure. The authors are expected to consider all review comments and 

to provide written responses, which are evaluated by 

the monitor (appointed by the RRC) and/or review coordinator (appointed by the administrative unit). A report 

GUiDeLiNeS FoR tHe Review oF

NATIONAL ACADEMIES REPORTS

Any National Academies report (including meeting summaries, signed papers, letter reports, or other study products) 

must be reviewed by a diverse group of experts other than its 

authors before it may be released outside the institution. 

This independent, rigorous review is a hallmark that distinguishes the National Academies from many other organizations offering scientific and technical advice on issues of 

national importance.

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