Appendix A to the Principles Governing IPCC Work 

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), Twenty-First Session (Vienna, 3 and 6-7 November 2003), TwentyNinth Session (Geneva, 31 August-4 September 2008), Thirty-Third Session (Abu Dhabi, 10-13 May 

2011), Thirty-Fourth Session (Kampala, 18-19 November 2011),Thirty-Fifth Session (Geneva, 6-9 

June 2012) and the Thirty-Seventh Session (Batumi, 14-18 October 2013) 

CONTENTS 

1. INTRODUCTION 

2. DEFINITIONS 

3. IPCC MATERIAL 

4. ASSESSMENT REPORTS, SYNTHESIS REPORTS, SPECIAL REPORTS AND 

METHODOLOGY REPORTS 

4.1 Convening a Scoping Meeting to Prepare Report Outline 

4.2 General Procedures for Preparing IPCC Reports 

4.3 Preparation of Reports by the Working Groups and the Task Force on National Greenhouse 

Gas Inventories 

4.3.1 Compilation of Lists of Potential Coordinating Lead Authors, Lead Authors, 

Contributing Authors, Review Editors and of Government Focal Points 

4.3.2 Selection of Lead Authors 

4.3.3 Preparation of Draft Report 

4.3.4 Review 

4.3.4.1 First Review (by Experts) 

4.3.4.2 Second Review (by Governments and Experts) 

4.3.5 Preparation of Final Draft Report 

4.4 Preparation, Approval and Acceptance of Summaries for Policymakers and Adoption of 

Overview Chapters of Methodology Reports 

4.5 Acceptance of Reports 

4.6 Reports Approved and/or Adopted by the Panel 

4.6.1 The Synthesis Report 

4.7 Addressing Possible Errors in Assessment Reports, Synthesis Reports, Special Reports and 

 Methodology Reports 

5. TECHNICAL PAPERS 

6. IPCC SUPPORTING MATERIAL 

7. WORKSHOPS AND EXPERT MEETINGS 

7.1 IPCC Workshops and Expert Meetings 

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7.2 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 PROCEDURE ON THE USE OF LITERATURE IN IPCC REPORTS 

ANNEX 3 IPCC PROTOCOL FOR ADDRESSING POSSIBLE ERRORS IN IPCC ASSESSMENT 

REPORTS, SYNTHESIS REPORTS, SPECIAL REPORTS AND METHODOLOGY REPORTS 

1. INTRODUCTION 

This 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. These Procedures for the Preparation, Review, 

Acceptance, Adoption, Approval and Publication of IPCC Reports were adopted at the Fifteenth 

Session of the IPCC (San Jose, 15-18 April 1999) and amended at the Twentieth Session 

(Paris, 19-21 February 2003), Twenty-First Session (Vienna, 3 and 6-7 November 2003), 

Twenty-Ninth Session (Geneva, 31 August-4 September 2008), Thirty-Third Session (Abu 

Dhabi, 10-13 May 2011), Thirty-Fourth Session (Kampala, 18-19 November 2011) and ThirtyFifth Session (Geneva, 6-9 June 2012). 

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 4.4 and for Overview 

Chapters of Methodology Reports. 

“Approval” of IPCC Summaries for Policymakers signifies that the material has been subject 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 the United Nations. 

“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. 

“Observer Organisation” refers to a body or an agency, whether national or international, 

governmental, intergovernmental or non-governmental which is qualified in matters covered by the 

IPCC and which has been admitted by the Panel in accordance with the IPCC Policy and Process 

for Admitting Observer Organisations to be represented at Sessions of the Panel and any of its 

Working Groups.1

 

																																																							

1

 The IPCC has a "Policy and Process for Admitting Observer Organizations". See: http://www.ipcc.ch/pdf/ipccprinciples/ipcc-principles-observer-org.pdf 
 “Reports” refer to the main IPCC materials (including Assessment, Synthesis, Methodology and 

Special Reports and their Summaries for Policymakers 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. 

“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” (“SPM”) 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 three categories: (1) Workshop proceedings and material from 

Expert Meetings which are either commissioned or supported by the IPCC, (2) software or 

databases to facilitate the use of the IPCC Methodology Reports, and (3) guidance material 

(guidance notes and guidance documents) to guide and assist in the preparation of comprehensive 

and scientifically sound IPCC Reports and Technical Papers. 

“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 policy-relevant but policy-neutral questions. They are composed of two sections as 

follows: (a) a Summary for Policymakers and (b) a longer report. 

“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. 

“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. 

“Working Group Bureau” refers to the elected members of the Bureau of a Working Group. It is 

chaired by Co-chairs, referred to as “Working Group Co-chairs”. 

3. IPCC MATERIAL 

There are three main classes of IPCC material, each of which is defined in Section 2. 

A. IPCC Reports (which include Assessment, Synthesis and Special Reports and their 

Summaries for Policymakers and Methodology Reports) 

B. Technical Papers 

C. Supporting Material 

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 4.4). 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 

(Section 4.4). 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 4.6). 

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during the review process. 

																																																							

B. Technical Papers are not accepted, approved or adopted by the Working Groups or the 

Panel but are finalised in consultation with the Bureau, which will function in the role of an 

Editorial Board (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 Convening a Scoping Meeting to Prepare Report Outline 

Each IPCC Assessment Report, Special Report, Methodology Report and Synthesis Report, as 

defined in Section 2 of Appendix A to the Principles Governing IPCC work, should be preceded by a 

scoping meeting that develops its draft outline (and explanatory notes as appropriate). Nominations 

for participation will be solicited from Government Focal Points, observer organisations, and Bureau 

members. Participants should be selected by the relevant respective Working Group Bureau/Task 

Force Bureau and, in case of the Synthesis Report, by the IPCC Chair in consultation with the 

Working Group Co-Chairs. In selecting scoping meeting participants, consideration should be given 

to the following criteria: scientific, technical and socio-economic expertise, including the range of 

views; geographical representation; a mixture of experts with and without previous experience in 

IPCC; gender balance; experts with a background from relevant stakeholder and user groups, 

including governments. The Working Group/Task Force Bureau and, in the case of the Synthesis 

Report, the IPCC Chair will report to the Panel on the selection process including a description of 

how the selection criteria for participation and any other considerations have been applied, and 

including a list of participants. 

Based on the report of the scoping meeting the Panel will decide whether to prepare a report and 

agree on its scope, outline, and the work plan including schedule and budget. 

4.2 General Procedures for Preparing IPCC Reports 

In Assessment Reports, Synthesis Reports, and Special Reports, Coordinating Lead Authors 

(CLAs), Lead Authors (LAs), and Review Editors (REs) of chapter teams are required to consider 

the range of scientific, technical and socio-economic views, expressed in balanced assessments. 

Authors should use calibrated uncertainty language that expresses the diversity of the scientifically 

and technically valid evidence, based mainly on the strength of the evidence and the level of 

agreement in the scientific, technical, and socio-economic literature. The IPCC guidance notes on 

addressing uncertainties are available on the IPCC website2

. 

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

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

Policymakers and 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 the 

Parties to the United Nations Framework Convention on Climate Change (UNFCCC) 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 

2

 See: http://www.ipcc.ch/pdf/supporting-material/uncertainty-guidance-note.pdf 
The drafts of IPCC Reports and Technical Papers which have been submitted for formal expert 

and/or government review, the expert and government review comments, and the author responses 

to those comments will be made available on the IPCC website as soon as possible after the 

acceptance by the Panel and the finalisation of the Report or Technical Paper. The IPCC considers 

its draft reports, prior to acceptance, to be pre-decisional, provided in confidence to reviewers, and 

not for public distribution, quotation or citation. 

4.3 Preparation of Reports by the Working Groups and the Task Force on National 

Greenhouse Gas Inventories 

It is essential that the 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 potential Coordinating Lead Authors, Lead Authors, Contributing Authors, 

Review Editors and of Government Focal Points. 

2. Selection of Coordinating Lead Authors, Lead Authors and Review Editors. 

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. 

4.3.1 Compilation of Lists of Potential Coordinating Lead Authors, Lead Authors, 

Contributing Authors, Review Editors and of 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, observer 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 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, 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 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, Review Editors and Government Focal Points are outlined in Annex 1. 

4.3.2 Selection of Coordinating Lead Authors, Lead Authors and Review Editors 

Coordinating Lead Authors, Lead Authors and Review Editors 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 observer 

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 chapter, a report or 

its summary shall aim to reflect: 

 the range of scientific, technical and socio-economic views and expertise; 

 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; 

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 a mixture of experts with and without previous experience in IPCC; 

 gender balance. 

The Working Group/Task Force Bureau will report to the Panel on the selection process and the 

extent to which the aims were achieved. The IPCC should make every effort to engage experts from 

the region on the author teams of chapters addressing specific regions, but should also engage 

experts from countries outside of the region when they can provide an essential contribution to the 

assessment. 

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 observer 

organisations who the Coordinating Lead Authors, Lead Authors and Review Editors are for 

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

chapter. 

4.3.3 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 internationallyavailable 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. 

4.3.4 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. 

Working Group/TFI Co-chairs should arrange a comprehensive review of reports in each review 

phase, seeking to ensure complete coverage of all content. Those parts of a Working Group report 

that are cross-cutting with other Working Group reports should be cross-checked through the 

relevant Authors and Co-chairs of that other Working Group. 

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

each Working Group/Task Force Bureau should normally select two to four 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 observer organisations. 

Review Editors should not be involved as authors or reviewers for material for which they are a 

Review 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. 

4.3.4.1 First Review (by Experts) 

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

review. The Working Group/Task Force Bureaux shall seek the participation of reviewers 

encompassing the range of scientific, technical and socio-economic views, expertise, and 

geographical representation and shall actively undertake to promote and invite as wide a group of 

experts as possible. This includes experts nominated as Coordinating Lead Authors, Lead Authors, 

Review Editors or Contributing Authors as included in lists maintained by the IPCC. Government 

Focal Points should be notified of the commencement of this process. 

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. 

4.3.4.2 Second Review (by Governments and Experts) 

A revised draft should be distributed by the appropriate Working Group/Task Force Bureau Cochairs 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. The Working Group/Task Force Bureaux shall seek the participation of reviewers 

encompassing the range of scientific, technical and socio-economic views, expertise, and 

geographical representation and shall actively undertake to promote and invite as wide a group of 

experts as possible. This includes experts nominated as Coordinating Lead Authors, Lead Authors, 

Review Editors or Contributing Authors as included in lists maintained by the IPCC. Government 

Focal Points should be notified of the commencement of this process. 

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. 

4.3.5 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, to the Panel for acceptance should be undertaken by 

Coordinating Lead Authors and Lead Authors in consultation with the Review Editors. If necessary, 

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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). 

4.4 Preparation, 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 Policymakers should be 

subject to simultaneous review by both experts and governments, a government round of written 

comments of the revised draft before the approval Session 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. 

The first review of the Summaries for Policymakers will take place during the same time period as 

the Expert Government Review of the Second Order Draft of the full report. The final draft of the 

Summaries for Policymakers prepared by the respective Working Groups and Overview Chapters of 

Methodology Report related to National Greenhouse Gas Inventories will be circulated for a final 

government round of written comments in preparation of the Session of the Working Group(s) that 

approves it or Session of the Panel that adopts it. 

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 socio-economic 

Assessment or Special Report accepted by the Working Group. Coordinating Lead Authors should 

be consulted in order to ensure that the Summary for Policymakers is fully consistent with the 

findings in the main report. 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. 

4.5 Acceptance of Reports 

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 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." 

4.6 Reports Approved and Adopted by the Panel 

Reports approved and adopted by the Panel will be the Synthesis Report of the Assessment 

Reports and other Reports as decided by the Panel whereby Section 4.4 applies mutatis mutandis. 

4.6.1 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 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 after nominations by the IPCC Chair in consultation with the Working Group 

Co-Chairs. In selecting the writing team for the Synthesis report, consideration should be given to 

the following criteria: scientific, technical and socio-economic expertise, including the range of 

views; geographical representation; a mixture of experts with and without previous experience in 

IPCC; gender balance. The IPCC Chair will report to the Panel on the selection process including a 

description of how the selection criteria for participation and any other considerations have been 

applied. 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. 

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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 observer 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." 

4.7 Addressing Possible Errors in Assessments Reports, Synthesis Reports, Special 

Reports and Methodology Reports 

The procedures to be followed for investigating possible errors in an Assessment Report, Synthesis 

Report, Special Report or Methodology Report and, if appropriate, implementing its correction are 

defined in the IPCC Protocol for Addressing Possible Errors in IPCC Assessment Reports, 

Synthesis Reports, Special Reports or Methodology Reports (see Annex 3). 

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 (UNFCCC) 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 4.3.1 and 

4.3.2 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 4.3.4.1 at least four 

weeks before the comments are due; 

e. are revised by the Lead Authors based upon the comments received in the paragraph above, 

and with assistance from at least two Review Editors per entire Technical Paper who are 

selected as per the procedures for selecting Review Editors for Assessment Reports, Synthesis 

Reports, Special Reports and Methodology Reports in Section 4.3.2 of this Appendix and carry 

out the roles as listed in Section 5 of Annex 1; 

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 UNFCCC 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." 

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12 

6. IPCC SUPPORTING MATERIAL 

Supporting material consists of three categories: 

(i) published reports and proceedings from Workshops and Expert Meetings within the scope 

of the IPCC work programme that have IPCC recognition, 

(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 have wide 

dissemination, and 

(iii) guidance material (guidance notes and guidance documents) that guides and assists in 

the preparation of comprehensive and scientifically sound IPCC Reports and Technical 

Papers. 

Procedures for the recognition of Workshops and Expert Meetings are given in Sections 7.1 and 

7.2. Arrangements for publication of supporting material should be agreed as part of the process of 

IPCC recognition or commissioned by Working Groups/the Task Force Bureau to prepare specific 

supporting material. All supporting material of categories (i) and (ii) should be formally and 

prominently described on the front and other introductory covers as: 

"Supporting material prepared for consideration by the Intergovernmental Panel on Climate 

Change. This supporting material has not been subject to formal IPCC review processes." 

Guidance material (guidance notes and guidance documents) is material to guide and assist 

authors in the preparation of comprehensive and scientifically sound IPCC Reports and Technical 

Papers. Guidance notes and documents are usually the responsibility of Working Group Bureaux, 

the Task Force Bureau or IPCC Chair as appropriate, but may also be commissioned by the Panel, 

the IPCC Executive Committee or the IPCC Bureau. Guidance notes and documents are developed 

and finalised by the relevant Working Group Bureaux, the Task Force Bureau or the IPCC Chair. 

The Executive Committee will oversee the consistency of these materials. Guidance notes and 

documents should be accessible together with the IPCC Principles and Procedures and published. 

7. WORKSHOPS AND EXPERT MEETINGS 

7. 1 IPCC Workshops and Expert Meetings 

IPCC Workshops and Expert Meetings are those that have been agreed upon in advance by an 

IPCC Working Group, or by the Panel as useful or necessary for the completion of the work plan of 

a Working Group, the Task Force on National Greenhouse Gas Inventories or a task of the IPCC. 

Only such activities may be designated as "IPCC" Workshops or Expert Meetings. Their funding 

should include full and complete provision for participation of experts from developing countries and 

countries with economies in transition. 

An IPCC Expert Meeting focuses on a specific topic bringing together a limited number of relevant 

experts. The relevant Working Group/Task Force Bureaux, or the IPCC Chair, will identify and 

select participants to Expert Meetings. 

An IPCC Workshop considers cross-cutting or complex topics requiring input from a broad 

community of experts. It requires nominations by Government Focal Points and, as appropriate, 

observer organisations. The relevant Working Group/Task Force Bureaux, or the IPCC Chair, may 

also nominate experts and will select the participants to the Workshop. 

Proposals for IPCC Workshops or Expert Meetings will be submitted to the Panel for its decision 

through the relevant Working Group/Task Force Bureaux, or the IPCC Chair. The proposals will 

include descriptions of the topic(s), and clarify the choice for an Expert Meeting or a Workshop. 
The composition of participants to Expert Meetings and Workshops shall aim to reflect: 

- The relevant range of scientific, technical and socio-economic views and expertise, 

- Geographical representation as appropriate, 

- A mixture of experts with and without previous experience in IPCC, 

- Gender balance. 

The relevant Working Group/Task Force Bureaux, or the IPCC Chair, may install a Scientific 

Steering Committee to assist in organizing these meetings, taking into account the criteria 

mentioned above. 

Government Focal Points should be notified of the list of invited participants to an Expert Meeting or 

Workshop at the earliest opportunity after the selection has taken place. 

The relevant Working Group/Task Force Bureaux, or the IPCC Chair, will convene the Expert 

Meeting or Workshop and report to the IPCC Bureau and Panel on the selection process, including 

a description of how the selection criteria and any other considerations for participation have been 

applied. 

The proceedings of IPCC Workshops and Expert Meetings should normally be published 

summarising the range of views presented at the meeting. Such proceedings should: 

- include a full list of participants; 

- indicate when and by whom they were prepared; 

- indicate whether and by whom they were reviewed prior to publication; 

- acknowledge all sources of funding and other support; 

- indicate prominently at the beginning of the document that the activity was held pursuant to a 

decision of the relevant Working Group or the Panel but that such decision does not imply 

Working Group or Panel endorsement or approval of the proceedings or any recommendations 

or conclusions contained therein. 

7.2 Co-sponsored Workshops and Expert Meetings 

IPCC co-sponsorship may be extended to other Workshops or Expert Meetings if the IPCC Chair, 

as well as the Co-Chairs of the relevant Working Group/Task Force Bureau determine in advance 

that the activity will be useful to the work of the IPCC. IPCC co-sponsorship of such an activity does 

not convey any obligation by the IPCC to provide financial or other support. In considering whether 

to extend IPCC co-sponsorship, the following factors should be taken into account: 

- whether full funding for the activity will be available from sources other than the IPCC; 

- whether the activity will be open to government experts as well as experts from nongovernmental organisations participating in the work of the IPCC; 

- whether provision will be made for participation of experts from developing countries and 

countries with economies in transition; 

- whether the proceedings will be published and made available to the IPCC in a time frame 

relevant to its work; 

- whether the proceedings will: 

- include a full list of participants; 

- indicate when and by whom they were prepared; 

- indicate whether and by whom they were reviewed prior to publication; 

- specify all sources of funding and other support; 

- prominently display the following disclaimer at the beginning of the document: 

"IPCC co-sponsorship does not imply IPCC endorsement or approval of these 

proceedings or any recommendations or conclusions contained herein. Neither the 

papers presented at the Workshop/Expert Meeting nor the report of its proceedings have 

been subjected to IPCC review." 

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14 

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 

1. LEAD AUTHORS 

Function: 

To be responsible for the production of designated sections addressing items of the work 

programme 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. 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 socio-economically sound 

and that faithfully represents, to the extent that this is possible, contributions by a wide 

variety of experts. The ability to work to deadlines is also a necessary practical requirement. 

Lead Authors are required to record in the Report views which cannot be reconciled with a 

consensus view but which are nonetheless scientifically or technically valid. 

Lead Authors may convene meetings with Contributing Authors, as appropriate, in the 

preparations of their sections or to discuss expert or government review comments and to 

suggest any Workshops or Expert Meetings in their relevant areas to the Working 

Group/Task Force Bureau Co-Chairs. The names of all Lead Authors will be acknowledged 

in the Reports. 

2. COORDINATING LEAD AUTHORS 

Function: 

To take overall responsibility for coordinating major sections of a Report. 

Comment: 

Coordinating Lead Authors will be Lead Authors with the added responsibility of ensuring 

that major sections of the Report are completed to a high standard, are collated and 

delivered to the Working Group/Task Force Bureau Co-Chairs in a timely manner and 

conform to any overall standards of style set for the document. 

Coordinating Lead Authors will play a leading role in ensuring that any crosscutting scientific 

or technical issues which may involve several sections of a Report are addressed in a 

complete and coherent manner and reflect the latest information available. 
The skills and resources required of Coordinating Lead Authors are those required of Lead 

Authors with the additional organisational 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. 

5. REVIEW EDITORS 

Function: 

Review Editors will assist the Working Group/Task Force Bureaux in identifying reviewers for 

the expert review process, ensure that all substantive expert and government review 

comments are afforded appropriate consideration, advise lead authors on how to handle 

contentious/controversial issues and ensure genuine controversies are reflected adequately 

in the text of the Report. 

Comment: 

There will be two to four 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 

15 
16 

to attend Sessions of the Working Group and of the IPCC to communicate their findings from 

the review process and to assist in finalising 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 programme, 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 observer organisation 

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). The full exchange of information is of particular importance. 
ANNEX 2 

PROCEDURE ON THE USE OF LITERATURE IN IPCC REPORTS 

This annex is provided to ensure that the IPCC process for the use of literature is open and 

transparent. In the assessment process, emphasis is to be placed on the assurance of the quality of 

all cited literature. Priority should be given to peer-reviewed scientific, technical and socio-economic 

literature if available. 

It is recognized that other sources provide crucial information for IPCC Reports. These sources may 

include reports from governments, industry, and research institutions, international and other 

organizations, or conference proceedings. Use of this literature brings with it an extra responsibility 

for the author teams to ensure the quality and validity of cited sources and information3

. In general, 

newspapers and magazines are not valid sources of scientific information. Blogs, social networking 

sites, and broadcast media are not acceptable sources of information for IPCC Reports. Personal 

communications of scientific results are also not acceptable sources. 

The following additional procedures are specified: 

1. Responsibilities of Coordinating, Lead and Contributing Authors 

The Coordinating Lead Authors will ensure that all sources are selected and used in accordance 

with the procedures in this Annex. 

The author team is required to critically assess information they would like to include from any 

source. Each chapter team should review the quality and validity of each source before 

incorporating information into an IPCC Report. Authors who wish to include information that is not 

publicly or commercially available are required to send the full reference and a copy, preferably 

electronically, to the relevant Technical Support Unit. For any source written in a language other 

than English, an executive summary or abstract in English is required. 

These procedures also apply to papers undergoing the publication process in peer-reviewed 

journals at the time of the government or expert review. 

All sources will be integrated into the reference section of the IPCC Report. 

2. Responsibilities of the Review Editors 

The Review Editors will support and provide guidance to the author team in ensuring the consistent 

application of the procedures in this Annex. 

3. Responsibilities of the Working Group /Task Force Bureau Co-Chairs 

For sources that are not publicly or commercially available, the Working Group/Task Force Bureau 

Co-Chairs coordinating the Report will make these sources available to reviewers who request them 

during the review process. 

4. Responsibilities of the IPCC Secretariat 

For sources that are not publicly or commercially available, the IPCC Secretariat will store these 

sources after publication of an IPCC report, in order to support the “IPCC Protocol for Addressing 

Possible Errors in IPCC Assessment Reports, Synthesis Reports, Special Reports or Methodology 

Reports”. 

																																																							

3

 see IPCC-XXXII/INF.4, Notes on the Informal Task Group on Procedures, containing general guidance on the use of 

literature in IPCC, page 7, section 2. 

http://www.ipcc.ch/meetings/session32/inf04_p32_review_ipcc_proc_proced_notes_informal_task_group.pdf 

17 
18 

ANNEX 3 

IPCC PROTOCOL FOR ADDRESSING POSSIBLE ERRORS IN IPCC ASSESSMENT REPORTS, 

SYNTHESIS REPORTS, SPECIAL REPORTS AND METHODOLOGY REPORTS 

Adopted by the Panel at the Thirty-Third Session (Abu Dhabi, 10-13 May 2011) and amended at 

the Thirty-Seventh Session (Batumi 14-18 October 2013) 

Preamble 

At its 32nd Session (October 2010), the IPCC Panel noted the proposed protocol for addressing 

errors in previous assessment reports (IPCC-XXXII/INF.8). The Panel tasked the IPCC Chairman, 

the IPCC Vice-Chairs, the Co-Chairs of Working Groups I, II and III and the Task Force on 

Inventories to take any necessary steps to ensure that this protocol is finalised and then used for 

evaluation of potential errors and developing errata as appropriate. The protocol is presented 

below. 

This protocol is intended to be used only to correct errors that could have been avoided in the 

context of the information available at the time the report was written. Its use should be reserved for 

errors of fact or accuracy. The protocol cannot be used to make changes that reflect new 

knowledge or scientific information that became available only after the literature cut-off date for the 

report in question. It cannot be used to propose the consideration of additional sources not cited in 

the existing assessment, unless directly relevant to an error of fact or accuracy. It must also not be 

invoked to reflect a difference in opinion compared with an author team or a new interpretation of 

knowledge or scientific information. 

This protocol is intended to address the full range of possible errors from typographical errors 

through complicated issues of sourcing, interpretation, analysis, or assessment, arising from the 

previously mentioned errors of fact or accuracy. 

Responsibility for implementing the error correction protocol rests with the current Co-Chairs of the 

relevant Working Group or Task Force product containing the alleged error. If the error is in a 

Synthesis Report, responsibility rests with the current IPCC Chairman. In all cases, the relevant 

Coordinating Lead Authors and Co-Chairs of the report containing the alleged error or, in the case 

of the Synthesis Report, the IPCC Chairman and relevant Working Group Co-Chairs at the time of 

that assessment, will be kept informed of the evaluation and participate as appropriate. 

The protocol is presented as a decision tree, which is based on a set of underlying principles. The 

procedure to be followed for investigating the claimed error and, if appropriate, implementing its 

correction depends on the location of the claimed error, i.e., whether it resides in a Chapter or the 

Technical Summary of a Working Group Contribution to an Assessment Report or of a Special 

Report, or in a Methodology Report, in the Summary for Policymakers of a Working Group 

Contribution or of a Special Report, or in the Overview Chapter of a Methodology Report, or in a 

Synthesis Report. 
IPCC Protocol for Addressing Errors 

in IPCC Assessment Reports, Synthesis Reports, Special Reports or Methodology Reports 

Principles underlying this protocol for handling errors: 

1. This protocol is intended to be used only to correct errors that could have been avoided in 

the context of the information available at the time the report was written. 

2. The IPCC Secretariat is the entry point for all error reporting. 

3. The IPCC Secretariat maintains an internal error tracking system. Entries are made in 

consultation with the current Co-Chairs of the relevant Working Group (WG) or Task Force 

(TF) or in case of an error in a Synthesis Report in consultation with the current IPCC 

Chairman. This system informs the leadership of IPCC and the Technical Support Units 

(TSUs), via a protected website, about the current status of all active error handling 

processes. 

4. To the extent possible, corrections should be based on consensus, consistent with the IPCC 

principles that form the foundation for the underlying reports. 

5. Responsibility for decisions at steps during the process is with the current WG or TF Bureau 

of the WG or TF product in which the alleged error resides. If the error is in a Synthesis 

Report, responsibility rests with the current IPCC Bureau. 

6. Responsibility for implementation is with the current Co-Chairs of the WG or TF product in 

which the alleged error resides. If the error is in a Synthesis Report, responsibility rests with 

the current IPCC Chairman. 

7. Original authors (Coordinating Lead Authors (CLAs), and Lead Authors (LAs) if necessary) 

must be involved as appropriate. Communication with them is via the current Co-Chairs of 

the relevant WG or TF (the IPCC Chairman in the case of the Synthesis Report). If any of 

the individuals identified as playing leading roles on behalf of author teams of previous 

reports are not available, then the current Co-Chairs of the WG or TF (the IPCC Chairman in 

the case of the Synthesis Report) will identify an individual or individuals best qualified to 

take over those roles. 

8. For alleged errors regarding the previous assessment cycles, the previous Co-Chairs of the 

relevant WG or TF and the previous IPCC Chairman need to be kept informed and may be 

consulted as appropriate. 

9. Handling of alleged errors must be coordinated across Chapters, Executive Summaries of 

Chapters, Technical Summaries of WG Contributions, Summaries for Policymakers for 

Working Groups, Synthesis Reports, Summaries for Policymakers for Synthesis Reports, 

and Overview Chapters of Methodology Reports. 

10. At the start of the process, the claimant is informed by the IPCC Secretariat about the next 

steps in a general way, and referred to this “IPCC Protocol for Addressing Possible Errors in 

IPCC Assessment Reports, Synthesis Reports, Special Reports or Methodology Reports”. 

The claimant will again be informed at the conclusion of the process. 

11. Errata are posted on the IPCC and WG or TF websites after the conclusion of the process. A 

short explanatory statement about the error may also be posted. 

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20 

Section 1: If the alleged error is in a Working Group Contribution or Special Report (Chapter 

or Technical Summary) or in a Methodology Report, start here. Otherwise, go to Section 2. 

For all alleged errors, it is essential to evaluate the possibility of consequences for the Summary for 

Policymakers of a WG Contribution to an Assessment Report, for the Summary for Policymakers of 

a Special Report, for the Overview Chapter of a Methodology Report, or for a Synthesis Report. 

Note: This section describes the procedure that is followed to address errors in a Working Group 

Contribution or a Special Report (Chapter or Technical Summary) or in a Methodology Report. 

Figure 1 provides an overview of the protocol for section 1. 

Step 1: 

An alleged error is reported to the IPCC Secretariat. If received elsewhere, it is passed to the IPCC 

Secretariat. A new entry is made in the internal error tracking system. 

Step 2: 

The IPCC Secretariat forwards the claim to the current Co-Chairs of the relevant WG (or TF). The 

IPCC Secretariat acknowledges receipt to the claimant, providing information about the next steps 

in a general way, and refers the claimant to the “IPCC Protocol for Addressing Possible Errors in 

IPCC Assessment Reports, Synthesis Reports, Special Reports or Methodology Reports”. 

Step 3:

The current WG or TF Co-Chairs and relevant Bureau decide whether action on the claim is 

warranted. They may consult previous Co-Chairs or CLAs of the relevant chapter. The condition for 

further processing is that one or more of the relevant current WG or TF Co-Chairs and relevant 

Bureau find that action is warranted. 

If consensus is reached that action is not warranted, the IPCC Secretariat informs the claimant and 

closes the case. 

If no consensus is reached or if the consensus is reached that action is warranted, the current WG 

or TF Co-Chairs consult the CLAs (or LAs if necessary) of the chapter. 

If the CLAs of the chapter with the alleged error agree that there is an error, continue with step 4A. 

If the CLAs of the chapter with the alleged error do not agree that there is an error, continue with 

step 4B. 

Step 4A: (for cases where the authors agree that there is an error)

For typographical errors, decisions on and posting of errata are handled by the current Technical 

Support Unit of the relevant WG or TF under the supervision of its Co-Chairs. The CLAs of the 

relevant chapters and WG or TF Bureau are informed. The IPCC Secretariat is informed, posts the 

errata, and closes the case. 

Otherwise, go to step 5A. 

Step 5A: (for cases where the authors agree that there is an error)

The current WG or TF Co-chairs and CLAs (and LAs if necessary) of the chapter with the alleged 

error evaluate the error and decide whether the correction requires expertise beyond the author 

team. 

If the author team has the appropriate expertise to construct an erratum, then one is constructed by 

the CLAs and submitted to the current WG or TF Bureau for approval. Following approval, the 

Secretariat informs the claimant and the erratum is posted on the IPCC and WG or TF websites. 

The case is then closed. 
If further expertise is required, then the relevant Co-Chairs and WG or TF Bureau appoint a Review 

Team containing, as a minimum, two experts who were not involved in drafting the chapter, plus at 

least one CLA or LA from the chapter with the error, and charges that Review Team with proposing, 

within two months’ time, an erratum statement. The Co-Chairs then submit this to the relevant WG 

or TF Bureau for approval. Following approval, the Secretariat informs the claimant and the erratum 

is posted on the IPCC and WG or TF websites. The case is then closed. 

If the authors, Review Team, and WG or TF Bureau fail to reach consensus on an erratum 

statement, then the WG or TF Co-Chairs inform the Executive Committee of the disagreement, and 

they ask the IPCC Chairman to appoint, within two months, an Independent Review Committee. 

This committee should consist of at least three experts not involved in drafting the chapter with the 

alleged error and not involved as a Bureau Member, CLA, or LA on the assessment with the alleged 

error or the current assessment. The Independent Review Committee, after consultation with the 

authors, the Review Team, the Co-Chairs, and the WG or TF Bureau, is tasked to propose a revised 

erratum. If consensus is now reached with the authors, the Co-Chairs then submit this to the 

relevant WG or TF Bureau for approval. Following approval, the Secretariat informs the claimant, 

and the erratum is posted on the IPCC and WG or TF websites. The case is then closed. 

If the current WG or TF Co-Chairs, the WG or TF Bureau and the relevant CLAs still cannot come to 

consensus, the current WG or TF Co-Chairs and the IPCC Chairman draft a “Contested Erratum” 

statement, signed by the IPCC Chairman. This is posted on the IPCC and WG or TF erratum 

websites. This statement reports the claimed error, and explains that issues have been raised but 

these cannot be resolved before this matter is reassessed in the present or next cycle. The IPCC 

Chairman and relevant WG or TF Co-Chairs decide on a communications strategy if needed. The 

case is then closed. 

Step 4B: (for cases where the authors do not agree that there is an error)

The WG or TF Co-Chairs inform the Executive Committee of the disagreement. The CLAs of the 

chapter with the alleged error provide the WG or TF Co-Chairs with a brief document explaining why 

the text in question does not contain an error. The WG or TF Co-Chairs then appoint, within two 

months, an Initial Review Group of two Bureau members and at least one CLA or LA from the 

current assessment if available, otherwise at least one expert who was not involved in drafting the 

chapter. The Initial Review Group is tasked to analyze the text in question and decide if they agree 

with the CLAs of the chapter with the alleged error. The response from the Initial Review Group is 

due in two months. 

If the Initial Review Group agrees that there was no error, then the WG or TF Co-Chairs inform the 

relevant CLAs and task them with preparing, within two months, a brief document explaining why 

the text in question was in fact not an error. The current WG or TF Co-Chairs submit the document 

to the current WG or TF Bureau for approval. After approval by the WG or TF Bureau, the IPCC 

Secretariat informs the claimant, and the case is closed. 

If the Initial Review Group finds there is an error, the WG or TF Bureau considers the report from 

the Initial Review Group, as well as from the authors, and aims to find consensus with the authors 

and the Initial Review Group on the development of an erratum. 

If consensus is reached, the CLAs, in consultation with the Initial Review Group, develop an erratum 

statement, which is submitted to the WG or TF Bureau for approval. Following approval, the IPCC 

Secretariat informs the Executive Committee and the claimant, and the erratum is posted on the 

IPCC and WG or TF websites. The case is then closed. 

If consensus is not reached continue with step 5B. 

Step 5B: (for cases where the authors do not agree that there is an error)

The WG or TF Co-Chairs inform the Executive Committee of the disagreement, and they ask the 

current IPCC Chairman to appoint, within two months, an Independent Review Committee. This 

committee should consist of at least three experts not involved in drafting the chapter with the 

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22 

alleged error and not involved as a Bureau Member, CLA, or LA on the assessment with the alleged 

error or the current assessment. The Independent Review Committee is tasked to evaluate the 

alleged error. 

If the Independent Review Committee agrees there is no error, they prepare, within two months, a 

brief document explaining why the text in question was in fact not an error. The current WG or TF 

Co-Chairs submit the document to the current WG or TF Bureau for approval. After approval by the 

current WG or TF Bureau, the IPCC Secretariat informs the claimant, and the case is closed. 

If the Independent Review Committee finds there is an error, they are tasked with providing, within 

two months, a proposed course of action. The WG or TF Bureau informs the relevant CLAs about 

the proposed action and, if agreement is found with them that there is an error and how to handle it, 

the authors develop an erratum statement, which is submitted to the WG or TF Bureau for approval. 

Following approval, the IPCC Secretariat informs the Executive Committee and the claimant, and 

the erratum is posted on the IPCC and WG or TF websites. The case is then closed. 

If the current WG or TF Co-Chairs, the WG or TF Bureau and the relevant CLAs still cannot come to 

consensus, the current WG or TF Co-Chairs and the IPCC Chairman draft a “Contested Erratum” 

statement, signed by the IPCC Chairman. This is posted on the IPCC and WG or TF erratum 

websites. This statement reports the claimed error, and explains that issues have been raised but 

these cannot be resolved before this matter is reassessed in the present or next cycle. The IPCC 

Chairman and relevant WG or TF Co-Chairs decide on a communications strategy if needed. The 

case is then closed. 

Note: before posting any erratum, the WG or TF Co-Chairs should evaluate possible consequences 

of the erratum for the Summary for Policymakers, Overview Chapter or Synthesis Report. If there 

are consequences, the relevant process in Sections 2 and/or 3 of this protocol needs to occur after 

the process in Section 1. 
Section 2: 

If the alleged error is in the Summary for Policymakers of a Working Group Contribution or 

of a Special Report, or in the Overview Chapter of a Methodology Report, start here. If it is 

in a Synthesis Report, go to Section 3.

Note: For errors in the Summary for Policymakers or Overview Chapter that arise from an 

underlying Chapter or the Technical Summary of a WG Contribution or of a Special Report or in a

Methodology Report, the error evaluation and correction process described in Section 1 of this 

protocol must be completed first to address the error in the underlying Chapter and/or Technical 

Summary or in a Methodology Report. 

Step 1: 

An alleged error is reported to the IPCC Secretariat. If received elsewhere, it is passed to the IPCC 

Secretariat. A new entry is made in the internal error tracking system. 

Step 2: 

The IPCC Secretariat forwards the claim to the current Co-Chairs of the relevant WG or TF. The 

IPCC Secretariat acknowledges receipt to the claimant, providing information about the next steps 

in a general way, and refers the claimant to the “IPCC Protocol for Addressing Possible Errors in 

IPCC Assessment Reports, Synthesis Reports, Special Reports or Methodology Reports”. 

Step 3:

The current WG or TF Co-Chairs and relevant Bureau decide whether action on the claim is 

warranted. They may consult previous Co-Chairs or CLAs of the relevant chapter. The condition for 

further processing is that one or more of the relevant current WG or TF Co-Chairs and relevant 

Bureau find that action is warranted. 

If consensus is reached that action is not warranted, the IPCC Secretariat informs the claimant and 

closes the case. 

If no consensus is reached or if the consensus is reached that action is warranted, the current WG 

or TF Co-Chairs consult the past WG or TF Co-Chairs who were authors of the Summary for 

Policymakers or Overview Chapter, as well as the CLAs of the relevant chapter of the underlying 

report. 

If the past WG or TF Co-Chairs and relevant CLAs agree that there is an error, continue with step 

4A. 

If the past WG or TF Co-Chairs and relevant CLAs do not agree that there is an error, continue with 

step 4B. 

Step 4A: (for cases where the past WG or TF Co-Chairs and relevant CLAs agree that there is an 

error)

For typographical errors, decisions on and posting of errata are handled by the current Technical 

Support Unit of the relevant WG or TF under the supervision of its Co-Chairs. The WG or TF Bureau 

and the past WG or TF Co-Chairs who were authors of the Summary for Policymakers or Overview 

Chapter are informed. The IPCC Secretariat is informed. It then informs the Executive Committee, 

posts the errata, and closes the case. 

Otherwise, go to step 5A. 

Step 5A: (for cases where the past WG or TF Co-Chairs and relevant CLAs agree that there is an 

error)

The current WG or TF Co-chairs and the past WG or TF Co-Chairs who were authors of the 

Summary for Policymakers or Overview Chapter with the alleged error, as well as the CLAs of the 

relevant chapter of the underlying report, evaluate the error. 

23 
24 

The past WG or TF Co-Chairs and relevant CLAs construct an erratum statement for the Summary 

for Policymakers or Overview Chapter and submit it to the current WG or TF Bureau for approval. 

Following WG or TF Bureau approval, the proposed erratum is submitted to the Panel for approval. 

To allow for rapid response, the Panel may delegate this approval step to the Executive Committee, 

which can decide that the erratum be posted on the IPCC and WG or TF websites and that the 

claimant be informed, or can decide to defer to the next session of the IPCC Bureau or of the Panel. 

Following approval, the Secretariat informs the claimant and the erratum is posted on the IPCC and 

WG or TF websites. The case is then closed. 

If the past WG or TF Co-Chairs and relevant CLAs fail to reach consensus on an erratum statement 

with the WG or TF Bureau, the Panel, or the Executive Committee, then the WG or TF Co-Chairs 

inform the Executive Committee of the disagreement, and they ask the IPCC Chairman to appoint, 

within two months, an Independent Review Committee. This committee should consist of at least 

three experts not involved in drafting the Summary for Policymakers or Overview Chapter with the 

alleged error and not involved as a Bureau Member, CLA, or LA on the assessment with the alleged 

error or the current assessment. The Independent Review Committee, after consultation with the 

past WG or TF Co-Chairs and relevant CLAs, the current WG or TF Co-Chairs, and the WG or TF 

Bureau, is tasked to propose a revised erratum. The current WG or TF Co-Chairs then submit this to 

the relevant WG or TF Bureau for approval. Following WG or TF Bureau approval, the proposed 

erratum statement is submitted to the Panel for approval. To allow for rapid response, the Panel 

may delegate this approval step to the Executive Committee, which can decide that the erratum be 

posted on the IPCC and WG or TF websites and that the claimant be informed, or can decide to 

defer to the next session of the IPCC Bureau or of the Panel. Following approval, the Secretariat 

informs the claimant, and the erratum is posted on the IPCC and WG or TF websites. The case is 

then closed. 

If the past WG or TF Co-Chairs and relevant CLAs, the current WG or TF Co-Chairs, the WG or TF 

Bureau, and the Panel or the Executive Committee still cannot come to consensus, the current WG 

or TF Co-Chairs and the IPCC Chairman draft a “Contested Erratum” statement, signed by the 

IPCC Chairman. This is posted on the IPCC and WG or TF erratum websites. This statement 

reports the claimed error, and explains that issues have been raised but these cannot be resolved 

before this matter is reassessed in the present or next cycle. The IPCC Chairman and relevant WG 

or TF Co-Chairs decide on a communications strategy if needed. The case is then closed. 

Step 4B: (for cases where the past WG or TF Co-Chairs and relevant CLAs do not agree that there 

is an error)

The current WG or TF Co-Chairs inform the Executive Committee of the disagreement. The past 

WG or TF Co-Chairs who were authors of the Summary for Policymakers or Overview Chapter with 

the alleged error, as well as the CLAs of the relevant chapter of the underlying report, provide the 

current WG or TF Co-Chairs with a brief document explaining why the text in question does not 

contain an error. The current WG or TF Co-Chairs then appoint, within two months, an Initial 

Review Group of two Bureau members and at least one CLA or LA from the current assessment if 

available, otherwise at least one expert who was not involved in drafting the Summary for 

Policymakers or Overview Chapter with the alleged error or relevant chapter of the underlying 

report. The Initial Review Group is tasked to analyze the text in question and decide if they agree 

with the past WG or TF Co-Chairs and relevant CLAs. The response from the Initial Review Group 

is due in two months. 

If the Initial Review Group agrees that there was no error, then the current WG or TF Co-Chairs 

inform the past WG or TF Co-Chairs and relevant CLAs and task them with preparing, within two 

months, a brief document explaining why the text in question was in fact not an error. The current 

WG or TF Co-Chairs submit the document to the current WG or TF Bureau for approval. After 

approval by the WG or TF Bureau, the IPCC Secretariat informs the claimant, and the case is 

closed. 
If the Initial Review Group finds there is an error, the WG or TF Bureau considers the report from 

the Initial Review Group, as well as from the authors, and aims to find consensus with the past WG 

or TF Co-Chairs and relevant CLAs and the Initial Review Group on the development of an erratum. 

If consensus is reached, the current WG or TF Co-Chairs, in consultation with the Initial Review 

Group, develop an erratum statement, which is submitted to the WG or TF Bureau for approval. 

Following WG or TF Bureau approval, the proposed erratum statement is submitted to the Panel for 

approval. To allow for rapid response, the Panel may delegate this approval step to the Executive 

Committee, which can decide that the erratum be posted on the IPCC and WG or TF websites and 

that the claimant be informed, or can decide to defer to the next session of the IPCC Bureau or of 

the Panel. Following approval, the IPCC Secretariat informs the claimant and the erratum is posted 

on the IPCC and WG or TF websites. The case is then closed. 

If consensus is not reached continue with step 5B. 

Step 5B: (for cases where the past WG or TF Co-Chairs and relevant CLAs do not agree that there 

is an error)

The current WG or TF Co-Chairs inform the Executive Committee of the disagreement, and they 

ask the current IPCC Chairman to appoint, within two months, an Independent Review Committee. 

This committee should consist of at least three experts not involved in drafting the Summary for 

Policymakers or Overview Chapter with the alleged error and not involved as a Bureau Member, 

CLA, or LA on the assessment with the alleged error or the current assessment. The Independent 

Review Committee is tasked to evaluate the alleged error. 

If the Independent Review Committee agrees there is no error, they prepare, within two months, a 

brief document explaining why the text in question was in fact not an error. The current WG or TF 

Co-Chairs submit the document to the current WG or TF Bureau for approval. After approval by the 

current WG or TF Bureau, the IPCC Secretariat informs the claimant, and the case is closed. 

If the Independent Review Committee finds there is an error, they are tasked with providing, within 

two months, a proposed course of action. The WG or TF Bureau informs the past WG or TF CoChairs and relevant CLAs about the proposed action and, if agreement is found with them that there 

is an error and how to handle it, the past WG or TF Co-Chairs and relevant CLAs develop an 

erratum statement, which is submitted to the WG or TF Bureau for approval. Following WG or TF 

Bureau approval, the proposed erratum statement is submitted to the Panel for approval. To allow 

for rapid response, the Panel may delegate this approval step to the Executive Committee, which 

can decide that the erratum be posted on the IPCC and WG or TF websites and that the claimant 

be informed, or can decide to defer to the next session of the IPCC Bureau or of the Panel. 

Following approval, the IPCC Secretariat informs the claimant and the erratum is posted on the 

IPCC and WG or TF websites. The case is then closed. 

If the current WG or TF Co-Chairs, the WG or TF Bureau and the past WG or TF Co-Chairs and 

relevant CLAs still cannot come to consensus, the current WG or TF Co-Chairs and the IPCC 

Chairman draft a “Contested Erratum” statement, signed by the IPCC Chairman. This is posted on 

the IPCC and WG or TF erratum websites. This statement reports the claimed error, and explains 

that issues have been raised but these cannot be resolved before this matter is reassessed in the 

present or next cycle. The IPCC Chairman and relevant WG or TF Co-Chairs decide on a 

communications strategy if needed. The case is then closed. 

25 
26 

Section 3: 

If the alleged error is in a Synthesis Report.

Note: For errors in the Synthesis Report that arise from an underlying Chapter or the Technical 

Summary or the Summary for Policymakers of a WG Contribution, the error evaluation and 

correction process described in Sections 1 and/or 2 of this protocol must be completed first to 

address the error in the underlying Chapter, Technical Summary and/or Summary for Policymakers. 

Step 1: 

An alleged error is reported to the IPCC Secretariat. If received elsewhere, it is passed to the IPCC 

Secretariat. A new entry is made in the internal error tracking system. 

Step 2: 

The IPCC Secretariat forwards the claim to the current IPCC Chairman, all WG Co-Chairs, and the 

Executive Committee. The IPCC Secretariat acknowledges receipt to the claimant, providing 

information about the next steps in a general way, and refers the claimant to the “IPCC Protocol for 

Addressing Possible Errors in IPCC Assessment Reports, Synthesis Reports, Special Reports or 

Methodology Reports”. 

Step 3:

The current IPCC Chairman, WG Co-Chairs, and IPCC Bureau decide whether action on the claim 

is warranted. They may consult previous Chairs, relevant WG Co-Chairs, or CLAs of the relevant 

chapter. The condition for further processing is that the current IPCC Chairman or one or more of 

the relevant current WG Co-Chairs and Bureau find that action is warranted. 

If consensus is reached that action is not warranted, the IPCC Secretariat informs the claimant and 

closes the case. 

If no consensus is reached or if the consensus is reached that action is warranted, the current IPCC 

Chairman consults the Chairman and the relevant WG Co-Chairs of the assessment with the 

alleged error. 

If the Chairman and the relevant WG Co-Chairs of the assessment with the alleged error agree that 

there is an error, continue with step 4A. 

If the Chairman and the relevant WG Co-Chairs of the assessment with the alleged error do not 

agree that there is an error, continue with step 4B. 

Step 4A: (for cases where the Chairman and the relevant WG Co-Chairs of the assessment with 

the alleged error agree that there is an error)

For typographical errors, decisions on and posting of errata are handled by the current Technical 

Support Unit of the Synthesis Report or of the relevant WG under the supervision of the IPCC 

Chairman and WG Co-Chairs as appropriate. The past Chairman as leader of the writing team for 

the Synthesis Report is informed. The IPCC Secretariat is informed, posts the errata, and closes 

the case. 

Otherwise, go to step 5A. 

Step 5A: (for cases where the Chairman and the relevant WG Co-Chairs of the assessment with 

the alleged error agree that there is an error)

The current IPCC Chairman and WG Co-chairs, in collaboration with the Chairman and the relevant 

WG Co-Chairs of the assessment with the alleged error, evaluate the error. 

The past Chairman and relevant WG Co-Chairs of the assessment with the alleged error (with 

relevant CLAs if appropriate) construct an erratum statement for the Synthesis Report and submit it 

to the current IPCC Bureau for approval. Following IPCC Bureau approval, the proposed erratum is 
submitted to the Panel for approval. To allow for rapid response, the Panel may delegate this 

approval step to the Executive Committee, which can decide that the erratum be posted on the 

IPCC and WG or TF websites and that the claimant be informed, or can decide to defer to the next 

session of the IPCC Bureau or of the Panel. Following approval, the Secretariat informs the 

claimant and the erratum is posted on the IPCC website. The case is then closed. 

If the past Chairman and relevant WG Co-Chairs of the assessment with the alleged error (with 

relevant CLAs if appropriate) fail to reach consensus on an erratum statement with the IPCC 

Bureau, the Panel, or the Executive Committee, then the current IPCC Chairman informs the 

Executive Committee of the disagreement, and appoints, within two months, an Independent 

Review Committee. This committee should consist of at least three experts not involved in drafting 

the Synthesis Report with the alleged error and not involved as a Bureau Member, CLA, or LA on 

the assessment with the alleged error or the current assessment. The Independent Review 

Committee, after consultation with the past Chairman and relevant WG Co-Chairs of the 

assessment with the alleged error (with relevant CLAs if appropriate), the current IPCC Chairman 

and WG Co-Chairs, and the IPCC Bureau, is tasked to propose a revised erratum. The current 

IPCC Chairman then submits this to the IPCC Bureau for approval. Following IPCC Bureau 

approval, the proposed erratum statement is submitted to the Panel for approval. To allow for rapid 

response, the Panel may delegate this approval step to the Executive Committee, which can decide 

that the erratum be posted on the IPCC and WG or TF websites and that the claimant be informed, 

or can decide to defer to the next session of the IPCC Bureau or of the Panel. Following approval, 

the Secretariat informs the claimant, and the erratum is posted on the IPCC website. The case is 

then closed. 

If the past Chairman and relevant WG Co-Chairs of the assessment with the alleged error (with 

relevant CLAs if appropriate), the current WG Co-Chairs, the IPCC Bureau, and the Panel or the 

Executive Committee still cannot come to consensus, the IPCC Chairman and the relevant WG CoChairs draft a “Contested Erratum” statement, signed by the IPCC Chairman. This is posted on the 

IPCC and WG erratum websites. This statement reports the claimed error, and explains that issues 

have been raised but these cannot be resolved before this matter is reassessed in the present or 

next cycle. The current IPCC Chairman and WG Co-Chairs decide on a communications strategy if 

needed. The case is then closed. 

Step 4B: (for cases where the Chairman and the relevant WG Co-Chairs of the assessment with 

the alleged error do not agree that there is an error)

The current IPCC Chairman informs the Executive Committee of the disagreement. The past 

Chairman and relevant WG Co-Chairs of the assessment with the alleged error (with relevant CLAs 

if appropriate) provide the current IPCC Chairman with a brief document explaining why the text in 

question does not contain an error. The current IPCC Chairman then appoints, within two months, 

an Initial Review Group of two Bureau members and at least one CLA or LA from the current 

assessment if available, otherwise at least one expert who was not involved in drafting the 

Synthesis Report with the alleged error or relevant chapter of an underlying WG report. The Initial 

Review Group is tasked to analyze the text in question and decide if they agree with the past 

Chairman, relevant WG Co-Chairs, and relevant CLAs. The response from the Initial Review Group 

is due in two months. 

If the Initial Review Group agrees that there was no error, then the current IPCC Chairman informs 

the past Chairman and relevant WG Co-Chairs of the assessment with the alleged error (with 

relevant CLAs if appropriate) and tasks them with preparing, within two months, a brief document 

explaining why the text in question was in fact not an error. The current IPCC Chairman submits the 

document to the current IPCC Bureau for approval. After approval by the IPCC Bureau, the IPCC 

Secretariat informs the claimant, and the case is closed. 

If the Initial Review Group finds there is an error, the IPCC Bureau considers the report from the 

Initial Review Group, as well as from the past Chairman, relevant WG Co-Chairs, and relevant 

CLAs, and aims to find consensus with the past Chairman, relevant WG Co-Chairs, relevant CLAs, 

and the Initial Review Group on the development of an erratum. 

27 
28 

If consensus is reached, the current IPCC Chairman, in consultation with the Initial Review Group, 

develops an erratum statement, which is submitted to the IPCC Bureau for approval. Following 

IPCC Bureau approval, the proposed erratum statement is submitted to the Panel for approval. To 

allow for rapid response, the Panel may delegate this approval step to the Executive Committee, 

which can decide that the erratum be posted on the IPCC and WG or TF websites and that the 

claimant be informed, or can decide to defer to the next session of the IPCC Bureau or of the Panel. 

Following approval, the IPCC Secretariat informs the claimant and the erratum is posted on the 

IPCC website. The case is then closed. 

If consensus is not reached continue with step 5B. 

Step 5B: (for cases where the Chairman and the relevant WG Co-Chairs of the assessment with 

the alleged error do not agree that there is an error)

The current IPCC Chairman informs the Executive Committee of the disagreement, and appoints, 

within two months, an Independent Review Committee. This committee should consist of at least 

three experts not involved in drafting the Synthesis Report with the alleged error and not involved as 

a Bureau Member, CLA, or LA on the assessment with the alleged error or the current assessment. 

The Independent Review Committee is tasked to evaluate the alleged error. 

If the Independent Review Committee agrees there is no error, they prepare, within two months, a 

brief document explaining why the text in question was in fact not an error. The current IPCC 

Chairman submits the document to the current IPCC Bureau for approval. After approval by the 

IPCC Bureau, the IPCC Secretariat informs the claimant, and the case is closed. 

If the Independent Review Committee finds there is an error, they are tasked with providing, within 

two months, a proposed course of action. The IPCC Bureau informs the past Chairman and relevant 

WG Co-Chairs of the assessment with the alleged error (and relevant CLAs if appropriate) about the 

proposed action and, if agreement is found with them that there is an error and how to handle it, the 

past Chairman, relevant WG Co-Chairs, and relevant CLAs develop an erratum statement, which is 

submitted to the IPCC Bureau for approval. Following IPCC Bureau approval, the proposed 

erratum statement is submitted to the Panel for approval. To allow for rapid response, the Panel 

may delegate this approval step to the Executive Committee, which can decide that the erratum be 

posted on the IPCC and WG or TF websites and that the claimant be informed, or can decide to 

defer to the next session of the IPCC Bureau or of the Panel. Following approval, the IPCC 

Secretariat informs the claimant and the erratum is posted on the IPCC website. The case is then 

closed. 

If the current IPCC Chairman, the IPCC Bureau, and the past Chairman, relevant WG Co-Chairs, 

and relevant CLAs still cannot come to consensus, the IPCC Chairman and the relevant Co-Chairs 

draft a “Contested Erratum” statement, signed by the IPCC Chairman. This is posted on the IPCC 

erratum website. This statement reports the claimed error, and explains that issues have been 

raised but these cannot be resolved before this matter is reassessed in the present or next cycle. 

The IPCC Chairman and WG Co-Chairs decide on a communications strategy if needed. The case 

is then closed. 
No Y es 

No Y es 

S t ep 4A: T ypo g r aphical 

e r r or? 

No Y es 

WG or TF T SU d r a f ts & 

posts e r r a tum and 

S t ep 5A: D oes author 

team have sucient 

expertise? 

No Y es 

WG or TF Co-Chair s 

appoint R eview T eam 

Propose e r r a tum 

Submit t o 

WG or TF Bu r eau 

C onsensus approval? 

No 

Y es 

No 

Y es 

CL A s d r a f t 

e r r a tum 

Submit t o 

WG or TF Bu r eau 

C onsensus 

app r o v al? 

No 

Y es 

R evise 

No Y es 

No Y es 

Y es 

P ost e r r a tum and 

notify claima n t 

No Y es 

C onsensus 

on e r r or? 

No 

Y es 

S t ep 2: IP C C S ec r eta r i a t 

ac k n o wledges and sends 

t o r ele v a n t WG C o - chairs 

CL A s a g r ee th a t 

the r e is an e r r or? 

S t ep 3: C o - chairs & WG 

Bu r eau - a c tion w a r r a n t ed? 

S ec r eta r i a t in f o r ms 

claima n t 

 S t ep 5B: WG or TF Co-Chairs inform 

IPCC ExCom; IPCC Chairman appoints 

 Independent Review Committee 

Is the r e an e r r or? 

Notify claimant 

S t ep 4B: WG or TF C o - Chairs 

in f o r m IP C C ExCom & appoint 

 I nitial R eview G r oup 

Is the r e an e r r or? 

Propose revised erratum 

Consensus app r o v al? 

CL A s d r a f t e r r a tum 

Consensus 

approval? 

The blue blue box represents the domain where authors agree that there 

is something to address. The red box is the domain where the authors, 

at least initially, do not agree that an error is present. The gure is designed

for a alleged error in the Chapters or Technical Summary of a WG contribution

(Section 1 in the protocol) . The process for a Summary for Policymakers or 

the Synthesis report parallels that for a potential error in a WG report, but 

with the responsible parties adjusted to reect responsibility and expertise.

Submit t o 

WG or TF Bu r eau 

No 

R evise 

 WG or TF Co-Chairs an d 

Chairman draft “Contested 

Erratum”; post and 

 notify claimant 

Post erratu m 

and notify claima n t 

 WG or TF Co-Chairs an d 

Chairman draft “Contested 

Erratum”; post and 

notify claimant 

WG or TF Co-Chairs inform IPCC 

ExCom; IPCC Chairman appoints 

Independent Review Committee 

Submit t o WG or TF Bureau 

D r a f t explanation 

Submit t o 

WG or TF Bu r eau 

Consensu s 

 approval ? 

Y es 

R evise 

No 

I ndepende n t R eview Committee 

 to propose course of action 

Consensus on e r r or? 

Consensus on e r r or? 

I ndepende n t R eview Committee 

 to propose revised erratum 

Submit t o WG or TF Bureau 

Y es 

No 

Step 1: Alleged error 

reported to IPCC 

Secretariat 

Figure 1: Schematic representation of IPCC Protocol for Addressing

Possible Errors in IPCC Assessment, Synthesis, Special, & Methodology Reports