Experts and author teams of the Intergovernmental Panel on Climate Change (IPCC) are meeting this week at the Universidad Católica in Santiago, Chile, to advance the first draft of the Working Group I contribution to the Seventh Assessment Report (AR7). The Working Group I report covers the physical science related to climate change.
The meeting, scheduled from April 21 to 24, 2026, is the second time the authors will be meeting in person following the first meeting held jointly with Working Group II and III in Paris in December 2025, where they began their work. The authors will meet two more times during the report preparation process to develop and refine the draft in line with IPCC’s principles and procedures.
“This is an important milestone in the preparation of the Working Group I contribution to the Seventh Assessment Report,” said IPCC Working Group I Co‑Chair, Robert Vautard.
“Building on their initial discussions in Paris, authors are now advancing the detailed scientific assessment needed to develop a robust First Order Draft of our report. These scientific exchanges are at the heart of the IPCC assessment process,” he added.
The Expert Review of the First Order Draft of the Working Group I report is scheduled from 10 August to 2 October 2026. In addition, as with all other IPCC reports, the Working Group I report will undergo two further formal review stages, including a joint review by governments and experts, before the final government review and approval by IPCC member governments at the Panel’s plenary session prior to public release.
“The multi‑stage review process ensures that the report is comprehensive, balanced and policy‑relevant without being policy‑prescriptive. This is how the IPCC builds trust in its assessments,” said IPCC Working Group I Co‑Chair Xiaoye Zhang.
The author teams of the Working Group I contribution to AR7 include 193 Coordinating Lead Authors, Lead Authors and Review Editors from 62 countries – 40% new to the IPCC process. 43% of these experts are women, and 46% come from developing countries and economies in transition including three from Chile.