Expert Review of the IPCC Special Report on 1.5°C Global Warming

Review starts from 31st July 2017 - Experts can register until September 17th.



The Expert Review is an integral part of the preparation of IPCC reports and contributors are acknowledged in the report once it is published.


The IPCC Procedures require the expert review process to be objective, open and transparent, with wide participation involving as many independent experts as possible. The revised wording of the Procedures approved at the 33rd Session of the IPCC in Abu Dhabi, 10-13 May 2011 stressed the need to seek a wide participation in the process. The purpose of the Expert Reviews is to ensure that the report is comprehensive, objective and balanced.

The First Order Draft (FOD) of the SR15 will be available for expert review for aneight week period from 31 July to 24 September 2017. The Second Order Draft (SOD) will be reviewed from 9 Januaryto 25 February 2018 by Experts and Government representatives.

Review Process

The IPCC Procedures require that the review be carried out by experts. This is not a public review and prospective Expert Reviewers are requested to provide information on their relevant scientific and technical expertise when they register.

The IPCC Procedures state that the review shall be undertaken by experts nominated by governments and participating organizations. In addition, the Working Group Bureaus shall seek the participation of the range of scientific, technical and socio-economic views, expertise, and geographical representation. The IPCC Secretariat will notify member governments and observer organisations of the call for registration and start of the review, inviting them to solicit the participation of their experts. All those previously nominated for a role in the SR15 but not selected will be invited to participate. Those individuals who have contacted the WGI TSU about the possibility of being an Expert Reviewer will also be contacted.

There will be an announcement on the IPCC website and on social media that the review registration site is open. All experts who submitted comments on the FOD will be invited to review the SOD and to submit further comments. The process includes an online registration system for Expert Reviewers that requests: contact details, a description of expertise related to the Chapters that will be reviewed, a list of up to five most relevant publications, and highest academic degree. A personal and non-transferable user name and password is generated for each Expert Reviewer upon successful completion of the registration.

To access the draft, Expert Reviewers must agree to the terms of the review, that all drafts and any supporting material such as unpublished literature are provided strictly for the purpose of the review and must not be cited, quoted, or distributed. Expert Reviewers are requested not to discuss the contents of the FOD in public fora such as blogs and other media. The final version of the SR15 will become public following its acceptance by the IPCC in September 2018.

Review comments should focus on substantive issues and must be provided in English, using the Excel comments sheet provided by the review system.

Constructive contributions are sought:

  • Considering the structure, comprehensiveness and balance in Chapters, including appropriate use of peer-reviewed literature;
  • Wherever possible, providing suggestions for revisions in terms of specific text and provide supporting evidence from the literature as appropriate;
  • Giving full citations for any suggested relevant papers
  • Considering ways of shortening the text without loss of relevant information;
  • Considering ways of improving the presentation of material graphically or through tables;
  • Avoiding suggesting revisions that would go beyond the Panel-approved outline for the Chapters of the Report
  • Recognizing that authors are required to work within page length constraints and must present a concise assessment of current knowledge, not a scientific review of how that knowledge was derived.

In accordance with the IPCC Procedures, copies of any non-published or not publicly available literature that is cited in the draft report can be provided by the WGI TSU to Expert Reviewers upon request during the review period. An online form is availablefor this purpose inthe review website.All Expert Review comments on the FOD and the SOD, together with the author responses to those comments, will be made available on an IPCC website after acceptance of the report by the Panel and its publication. Review comments will not be anonymous and Expert Reviewers will be identified as part of the public record of the AR6, with their name, affiliation, and country of residence being published in the Annex of Reviewers in the final SR15 report.

Expert Registration

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