The IPCC Sixth Assessment Report (AR6)

The Intergovernmental Panel on Climate Change (IPCC) will publish their Sixth Assessment Report (AR6) in stages, between August 2021 and September 2022.

AR6 is the latest set of reports to assess scientific knowledge on climate change. The report will look at:

  • past, present and future climate
  • the impact of climate change and future risks
  • options for adaptation and mitigation.

What is an IPCC Assessment Report?

Assessment Reports provide scientific evidence for policymakers all over the world to use in decisions about how to tackle climate change. The reports are a resource for global climate negotiations, such as the 26th Conference of the Parties (COP26), hosted in Glasgow in November 2021.

Leading scientists from around the world compile IPCC reports, volunteering their time to assess evidence from scientific, technical and socio-economic publications. Many Met Office scientists have played a leading role in writing the reports, which also widely use Met Office science.

As part of the process, the reports go through several rounds of review from many experts, providing transparency and ensuring the reports are as objective as possible.

IPCC Working Groups

Three Working Groups prepare the report for the IPCC. Each looks at a difference aspect of the science related to climate change.

  • Working Group 1 focus on the physical science that underpins past, present and future climate change.
  • Working Group 2 assess climate impacts, the vulnerability of socio-economic and natural systems to climate change, and options for adaptation.
  • Working Group 3 focus on climate change mitigation, assessing methods for reducing emissions and removing greenhouse gases from the atmosphere.

IPCC Working Group 1

The first part of the AR6 report to be published is from Working Group 1. It includes a Summary for Policymakers (SPM) and a much longer technical report, which provides detail on all the evidence considered.

Over 200 scientists prepared this part of the report, which is based on more than 14,000 citations to other documents, papers or reports. The authors have also dealt with over 75,000 comments during the extensive review process.

IPCC Working Group 2

The AR6 Working Group 2 report was published in February 2022. This second part of the AR6 report covers the impacts of climate change and efforts to adapt to them, as well as the vulnerability of natural and man-made systems.

This part of the report included 270 authors who considered over 34,000 citations and over 62,000 review comments.

IPCC Working Group 3

The AR6 Working Group 3 report was published in April 2022. This third and final part of the AR6 report focuses on climate change mitigation, including past and future efforts at reducing greenhouse gas emissions across a variety of economic sectors.

More than 18,000​ citations of papers and other resources contributed to this report, collated by 278 authors and covered by over 59,000 comments from reviewers.

What is the IPCC?

The World Meteorological Organisation (WMO) and the United Nations Environment Programme (UNEP) created the IPCC. It is the United Nations’ body for assessing climate change science, including 195 member countries.

Scientists from all over the world contribute to the IPCC, providing neutral, policy-relevant (but not policy-prescriptive) assessments of the state of knowledge on climate change. The IPCC present this in Assessment Reports or Special Reports.

The IPCC produces Assessment Reports approximately every 6 years, with the first released in 1990. Since this first report, the evidence of human influence on the climate has continued to strengthen.

IPCC reports

The IPCC has published three other Special Reports over the last few years: