How are IPCC reports prepared?
The preparation and approval process is the same for all three volumes of the IPCC (Fig. 1).
In a first step, the scientific community, political decision-makers and others define concrete topics and the structure of the report. For each chapter, a team of authors is assembled, selected on the basis of their expertise. The composition of the author teams also aims to reflect a range of disciplines and backgrounds.
In the actual writing process, the authors use already published findings, if possible from scientific journals, compile them and evaluate them. The drafts then go through a multi-stage review process. The first draft of the report is reviewed by scientific experts; the second draft is additionally reviewed by government representatives of the member states. The respective authors must give due consideration to any comment or criticism and justify changes in writing.
The final draft is turned into a Summary for Policymakers (SPM), which is discussed sentence by sentence by the scientific community and IPCC member states during a multi-day plenary session. The aim of the summary is to express the complicated interrelations in a clear and understandable way. However, wording may only be changed by the governments if the statement is covered by the report, so that scientific correctness remains ensured. With the formal approval of the Assessment Report and the Summary for Policymakers, the member states officially recognize the scientific statements of the IPCC.