Review and Scoping process of the Working group I contribution to the Sixth Assessment Report


All IPCC reports undergo two stages of review. A First-Order Draft is reviewed by experts. Following the expert review, authors develop a Second-Order Draft based on the comments received. This draft then undergoes a second review by both governments and experts. Authors will prepare a Final Draft based on the comments received during the second review. The Final Draft is distributed to governments at the time of the final government review of the Summary for Policymakers.

The First-Order Draft of the Working Group I contribution to AR6 has undergone an expert review ( 29 April – 23 June 2019). The Second-Order Draft  was reviewed by  governments and experts from  2 March 2020. It was initially scheduled to end on 26 April,  but closed on 5 June 2020 due to changes to the schedule resulting from the COVID-19 pandemic.




The scoping meeting for the Sixth Assessment Report (AR6) took place in Addis Ababa (Ethiopia) from 1 to 5 May 2017. The draft outlines were approved by the Panel when it met in September 2017

The approved outline of the Working Group I contribution to the Sixth Assessment Report is available  here .

The scoping process was guided by the IPCC Chair’s Vision Paper

call for nomination of experts  to attend the scoping meeting was issued to governmentsobserver organizations and IPCC bureau members. They were requested to submit their nominations via their focal points before midnight (CET) on 31 October 2016. The deadline was later extended to Monday 14 November 2016

In order to determine robust areas of consideration, participants in the Scoping Meeting had a broad understanding of climate change and related issues, and collectively had expertise in the following areas:

Working Group I

  • Climate system (atmosphere, ocean, land surface, cryosphere): observations (past and present), processes, and interactions.
  • Natural and anthropogenic drivers of climate change (land use, well-mixed greenhouse gases, short-lived forcers including aerosols), carbon and other biogeochemical cycles.
  • Climate modelling, model evaluation, predictions, scenarios and projections, detection and attribution, on global and regional scales.
  • Earth system feedbacks and dynamical responses, including abrupt change.
  • Climate variability, climate phenomena and teleconnections, extremes and implications for regional climate.

Cross-cutting areas of expertise

  • Co-benefits, risks and co-costs of mitigation and adaptation, including interactions and trade-offs, technological and financial challenges and options.
  • Ethics and equity: climate change, sustainable development, gender, poverty eradication, livelihoods, and food security.
  • Perception of risks and benefits of climate change, adaptation and mitigation options, and societal responses, including psychological and sociological aspects.
  • Climate engineering, greenhouse gas removal, and associated feedbacks and impacts.
  • Regional and sectorial climate information.
  • Epistemology and different forms of climate related knowledge and data, including indigenous and practice-based knowledge.

Regional expertise

  • Africa
  • Europe
  • Asia
  • Australasia
  • North America
  • Central and South America
  • Polar regions
  • Small islands
  • Ocean

Nominations page


On 21 September 2016, the IPCC Secretariat sent out a pre-scoping questionnaire to governments and observer organizations to identify policy relevant questions and scientific and technical topics to be addressed in the Sixth Assessment Report (deadline: 30 November 2016, extended to 12 December 2016). The responses received were synthesized and made available to the participants of the AR6 Scoping Meeting and the Panel.