ESMO Members Contribute to the IPCC’s Seventh Assessment Report

Several members of the Earth System Modelling and Observations (ESMO) project have been selected to serve as authors and reviewers for the Intergovernmental Panel on Climate Change (IPCC) Seventh Assessment Report (AR7). This recognition highlights both their scientific expertise and ESMO’s contribution to advancing global understanding of the climate system.

What is the IPCC Assessment Report?

The IPCC is the United Nations body for assessing the science related to climate change. Its comprehensive Assessment Reports, published approximately every six to seven years, provide authoritative evaluations of the current state of scientific, technological and socio-economic knowledge on climate change. They are widely regarded as the most influential scientific documents shaping international climate policy and negotiations, including the United Nations Framework Convention on Climate Change (UNFCCC) and the Paris Agreement.

Working Group I: The Physical Science Basis

The IPCC Assessment Report is prepared by three Working Groups, each focusing on different dimensions of climate change, including Impacts, Adaptation and Vulnerability (WG II) and Mitigation of Climate Change (WG III). Working Group I (WG I) assesses the physical science basis of climate change, including:

• Observations of the atmosphere, ocean, cryosphere, and land

• Reconstructions of past climate

• Processes that drive climate variability and change

• Future projections based on climate models

• Climate information and services

WG I provides the scientific foundation for understanding how and why the climate is changing, questions that are central to ESMO’s mission of integrating observations and Earth system models.

ESMO’s Contribution to AR7

All of the ESMO members selected will contribute within Working Group I, either as Coordinating Lead Authors, Lead Authors, or Review Editors. Their participation ensures that cutting-edge knowledge on Earth system modelling and observations will be represented in AR7, strengthening the scientific basis for global decision-making on climate action.

Below is a list of authors and reviewers who are part of ESMO:

Chapter 5: Scenarios and projected future global temperatures

• June-Yi Lee (WGSIP Emeritus Co-chair), Coordinating Lead Author

• Tilo Ziehn (WGCM Co-chair), Lead Author

Chapter 6: Global projections of Earth system responses across time scales

• Yixiong Lu (ESMO Scientific Steering Group member), Lead author

Chapter 7: Projections of regional climate and extremes

• Fatima Driouech (ESMO Scientific Steering Group member), Review Editor

Chapter 8: Abrupt changes, low-likelihood high impact events and critical thresholds, including tipping points, in the Earth system

• Anastasia Romanou (WGCM Member), Coordinating Lead Author

• Shuting Yang (WGCM Member), Lead Author

Chapter 9: Earth system responses under pathways towards temperature stabilization, including overshoot pathways

• Roland Séférian (ESMO Scientific Steering Group member), Coordinating Lead Author

• Michio Kawamiya (ESMO Scientific Steering Group member), Review Editor

Chapter 10: Climate information and services

• Masilin Gudoshava (WGSIP Member), Coordinating Lead Author

Looking Ahead

The preparation of the report follows a rigorous, multi-stage review process designed to ensure scientific accuracy and transparency as detailed here. Over the next several years, the selected authors will develop a First Order Draft, which will undergo expert review to assess its completeness and validity. Feedback from this stage will inform the Second Order Draft and the Summary for Policymakers, both of which are subject to further review and approval by governments and IPCC bodies. Throughout the process, every review comment and author response is made publicly available, and the degree of confidence in scientific findings is explicitly stated, underscoring the report’s commitment to openness and credibility.

The Seventh Assessment Report, expected later in 2029, will be a cornerstone in guiding international efforts to address climate change, and ESMO is honored to be part of this collective scientific endeavor.