In cooperation with the U.S. Department of State, the U.S. Global Change Research Program (USGCRP) seeks expert comment on the fourth and final volume of the Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report (AR6) — the Synthesis Report. A Federal Register Notice has been published to promote the activity.

The Government and Expert Review runs 10 January - 20 March 2022. USGCRP will accept comments until 11:59 p.m. ET, Tuesday, 1 March 2022, via its Review and Comment (R&C) System. All comments must be input via the R&C System if they are to inform the U.S. Government submission; additional information — including context, instructions, the draft report itself, and the comments collection vehicle — can be found on the landing page, accessible after registering and agreeing to terms of the review.

Experts are advised that they have the option to submit comments direct to IPCC. To participate in the concurrent Expert Review of the draft Synthesis Report, managed by IPCC, click here. The IPCC Secretariat will accept registrations until 13 March 2022. To avoid duplication, U.S. experts are requested not to submit via both the USGCRP and IPCC mechanisms. Pick a single conduit.

The draft Synthesis Report — which includes a Summary for Policymakers and a longer underlying report — can only be based on the three Working Group contributions to the AR6 and the three Special Reports undertaken during the AR6 cycle. As yet, the Synthesis Report does not represent an approved product of the IPCC. According to the IPCC rules and procedures, draft IPCC reports should not be cited, quoted, or distributed other than for the purpose of review. In enabling the U.S. scientific expert community to review and provide comments on the report, participants are expected to abide by IPCC policy.