Intergovernmental Panel
on Climate Change (IPCC)

The AR4 Synthesis Report	The Physical Science Basis	Impacts, Adaptation and Vulnerability	Mitigation of Climate Change

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The AR4 Synthesis Report
	Full Report Summary for Policymakers Order at GCRIO
Working Group I Report "The Physical Science Basis"
Working Group I Contribution to the Fourth Assessment Report of the IPCC Intergovernmental Panel on Climate Change. IPCC Fourth Assessment Report on scientific aspects of climate change for researchers, students, and policymakers. Published October 2007.
	Full Report Summary for Policymakers Order at GCRIO
Working Group II Report "Impacts, Adaptation and Vulnerability"
Working Group II contribution to the Fourth Assessment Report of the IPCC Intergovernmental Panel on Climate Change. IPCC Fourth Assessment Report on climate change impacts, adaptation and vulnerability for researchers, students, policymakers. Published March 2008
	Full Report Summary for Policymakers Order at GCRIO
Working Group III Report "Mitigation of Climate Change"
Working Group III contribution to the Fourth Assessment Report of the IPCC Intergovernmental Panel on Climate Change. IPCC Fourth Assessment Report on the mitigation of climate change for researchers, students, and policymakers. Published January 2008.
	Full Report Summary for Policymakers Order at GCRIO

Announcements

U.S. Department of State Seeks Public Comment on Future Work of the Intergovernmental Panel on Climate Change. Federal Register Notice published, with comments due via IPCC-future@climatescience.gov by COB Friday, 29 February 2008. [comment period now closed] (link posted 08 February 2008)

Towards New Scenarios for Analysis of Emissions, Climate Change, Impacts, and Response Strategies. Report of the Intergovernmental Panel on Climate Change (IPCC) Expert Meeting, held on 19-21 September, 2007, in Noordwijkerhout, the Netherlands. Available for expert review until 23 January 2008.  [comment period now closed] (posted 3 January 2008)

Summary for Policymakers of the IPCC Fourth Assessment Synthesis Report [PDF]. Released 17 November 2007. See also: Press Briefing Via Conference Call by Senior Administration Officials on IPCC Report, transcript issued by the White House Office of the Press Secretary on 16 November 2007. (link posted 19 Nov 2007)

Frequently Asked Questions from the IPCC's "Climate Change 2007: The Physical Science Basis." Nineteen FAQs (each as a separate PDF file) from the Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, first published in 2007 (link posted 29 Aug 2007)

Climate Change 2007: Impacts, Adaptation and Vulnerability. The Working Group II contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. The report includes Chapter 14 on North America. (link posted 6 August 2007)

Available upon request: U.S. Government comments on the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Synthesis Report.  To obtain a copy, please submit a request to .  (this notice was posted 24 July 2007).  The comments are derived from an expert review process announced in a Federal Register notice published on 21 May 2007.

Now available from Working Group I (links posted 5 July 2007):

• Powerpoint files containing the figures from the Summary for Policymakers (SPM), Technical Summary (TS), and individual chapters of Working Group I's contribution to the Fourth Assessment Report (Climate Change 2007: The Physical Science Basis)
• Files containing reviewers' comments and the authors' responses to those comments

Request for expert review of Climate Change 2007: Synthesis Report.  The U.S. Climate Change Science Program requests expert review of this fourth and final volume of the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report.  Comments were due 27 June 2007 [comment period now closed].  See also the Federal Register notice (dtd 21 May 2007)

United States Joins In Approving Summary Report on Climate Change Mitigation.  Media note (4 May 2007) from the U.S. Department of State.See also:  Climate Change 2007: Mitigation of Climate Change,  links to information related to the Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. (posted 9 May 2007)

International Scientific Panel Approves Report on Climate Change Impacts, Adaptation and Vulnerability.  Panel indicates high confidence that “anthropogenic warming over the last three decades has had a discernible influence on many physical and biological systems” Press release (dated 6 April 2007) from the U.S. Climate Change Science Program.  See also: Climate Change 2007: Impacts, Adaptation, and Vulnerability.  Summary for Policymakers, links to information related to the Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. (posted 6 April 2007)

U.S. Climate Change Science Program Provides Key Contributions to IPCC Fourth Assessment, press release (dtd 16 February 2007) from the U.S. CCSP.(posted 16 February 2007)

Climate Change 2007. The Physical Science Basis.  Links to information related to the Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change.  (link added 2 Feb 2007)

Available upon request: U.S. Government collation in support of the Expert and Government Review of the Intergovernmental Panel on Climate Change (IPCC) Working Group III Fourth Assessment Report.  To obtain a copy, please submit a request to . (posted 18 September 2006).

Intergovernmental Panel on Climate Change (IPCC) Working Group III Contribution to the Fourth Assessment Report of the IPCC:  Government and Expert Review.  The second-order draft of Climate Change 2007: Mitigation of Climate Change is available for expert and government review.   Comments were due 23 August 2006 [comment period now closed].  The draft report is available along with instructions and related materials.  See also Federal Register notice (dtd 24 July 2006).  (links posted 1 August 2006).

Available upon request: U.S. Government collation in support of the Expert and Government Review of the Intergovernmental Panel on Climate Change (IPCC) Working Group II Fourth Assessment Report.  To obtain a copy, please submit a request to . (posted 25 July 2006).

Available upon request: U.S. Government collation in support of the Expert and Government Review of the Intergovernmental Panel on Climate Change (IPCC) Working Group I Fourth Assessment Report.  To obtain a copy, please submit a request to . (posted 13 June 2006).

Intergovernmental Panel on Climate Change (IPCC) Working Group II Contribution to the Fourth Assessment Report of the IPCC:  Government and Expert Review.  The second-order draft of Climate Change 2007: Impacts, Adaptation, and Vulnerability is available for expert and government review.   Comments are due 28 June 2006.  The draft report is available along with instructions and related materials.  See also Federal Register notice (dtd 26 May 2006).  (links posted 26 May 2006).[Note: The comment period is closed and the draft report no longer is available.]

Intergovernmental Panel on Climate Change (IPCC) Working Group I Contribution to the Fourth Assessment Report of the IPCC:  Government and Expert Review.  The second-order draft of Climate Change 2007: The Physical Science Basis is available for expert and government review.  The draft report is available along with instructions and related materials.  Comments were due 9 May 2006 [comment period now is closed] . See also Federal Register notice (dtd 7 April 2006).  (posted 7 April 2006).

Invitation for Expert Review of First Order Draft, IPCC Working Group III Fourth Assessment Report.  [PDF] Invitation from Working Group co-chairs, Bert Metz and Ogunlade Davidson.  The draft report is available for review by experts from 28 November 2005 until 20 January 2006. If you wish to review the report, please notify the IPCC via email at ipcc3tsu@mnp.nl, noting your contact details and your area of expertise. (posted 12 January 2006)

Intergovernemental Panel on Climate Change (IPCC) Working Group (WG) I First Order Draft Review.  The First Order Draft of the WG I report is available for expert review from 12 September to 4 November 2005. If you would like to review this draft and have not already provided IPCC Working Group I with your contact details please register. [Update: Registration CLOSED on 21 Oct. 2005.  Reviews are due Friday, 4 Nov. 2005.]

Intergovernemental Panel on Climate Change (IPCC) Working Group II First Order Draft Review.  The First Order draft of the WG II report is available for expert review from 12 September to 4 November 2005. If you would like to review this draft and have not already provided your contact details to IPCC Working Group II, please inform the Technical Support Unit at ipcc-wg2@metoffice.gov.uk.

Start of Government/Expert Review of 2006 IPCC Guidelines for National Greenhouse Gas Inventories.  Letter (dtd 12 September 2005) to expert reviewers from Thelma Krug and Taka Hiraishi (Co-Chairs, Task Force Bureau, National Greenhouse Gas Inventories Programme, Intergovernmental Panel on Climate Change [IPCC]).  The letter invites reviewers to contribute to the Expert Review of the Second Order Draft of the 2006 IPCC Guidelines for National Greenhouse Gas Inventories (2006 Guidelines). The review started on 12
September 2005 and lasts for eight weeks until 7 November. (posted 4 October 2005)

IPCC Special Report on Carbon Dioxide Storage and Capture, U.S. Government Review. Invitation to comment on the draft special report from the Intergovernmental Panel on Climate Change (IPCC), Working Group III.  Page includes links to instructions and to drafts.  To have comments considered as part of the official U.S. position, all U.S. expert comments must be sent to CCSPO at srccs-USGreview@climatescience.gov by COB 23 February 2005. See also Federal Register Notice, 25 January 2005. [comment period closed on 23 Feb 2005] (links posted 13 January 2005)

IPCC/TEAP Special Report on Safeguarding the Ozone Layer and the Global Climate System: Issues Related to Hydrofluorocarbons and Perfluorocarbons.  U.S. Government Review.   Draft special report from the Intergovernmental Panel on Climate Change (IPCC) and the Technology and Economic Assessment Panel (TEAP).  The report, posted for review, assesses scientific and technical information related to alternatives to ozone-depleting substances.  The draft was open for comments until 2 November 2004.   [review period now closed]  See also Federal Register Notice, dated 29 September 2004. (links updated 29 September 2004)

21-23 September 2004.  Tokyo, Japan.  IPCC Expert Meeting on Industrial Technology Development, Transfer and Diffusion.  Sponsor: Intergovernmental Panel on Climate Change, Working Group III.  Contact: John Kessels, Technical Support Unit Working Group III, p/o ECN, Badhuisweg 3 / P.O. Box 37154, 1030 AD Amsterdam, THE NETHERLANDS.  Tel: +31-224-564882.  Fax +31-20-4922812.  Email: Kessels@ecn.nl

Scientific Workshop on Climate Sensitivity (Paris, France, on 26-29 July 2004).  Announcement (dtd 6 October 2003) from the IPCC, sent to Foreign Affairs ministries. Governments had until 24 November 2003 to nominate experts to participate in the workshop. Though the deadline has passed, this announcement is posted here as part of an overall effort to inform the public about U.S. participation in the IPCC. In the future, we will seek to promptly post such announcements on this page.

Other Documents:

Principles Governing IPCC Work.[PDF]   Approved at the Fourteenth Session (Vienna, 1-3 October 1998) on 1 October 1998

Appendix A.  Procedures for the Preparation, Review, Acceptance, Adoption, Approval and Publication of IPCC Reports.  [PDF] Adopted at the Fifteenth Session of the IPCC (San Jose, 15-18 April 1999) and revised, on a provisional basis, at the Twentieth Session of the IPCC (Paris, 19-21 February 2003).

Appendix B.  Financial Procedures for the Intergovernmental Panel on Climate Change (IPCC).  [PDF] Originally adopted at the Twelfth Session of the IPCC (Mexico City, 11-13 September 1996)