The Fourth Climate Change Risk Assessment – Independent Assessment (CCRA4-IA) Technical Report

Acknowledgements

Science Lead: Jason A. Lowe

Project Delivery: Mark Harrison, Rachel J. Perks and Robert Ivory

Engagement Leads: Daniel Williams, Tyrone Dunbar

CCC Secretariat: Florence Bates, Elizabeth Fuller, Richard Millar, Olivia Shears

Science Assurance Group: Lee Chapman, Chris Dent, Hayley Fowler and Jason A. Lowe

The Met Office led a consortium of experts from across academia, the public, private and third Sector to develop the Technical Report. We would like to thank Lead Authors, who have supported the Met Office from the following institutions: University of Birmingham, University of Bristol, University of Exeter, University College London, University of Reading, Centre for Ecology & Hydrology, and Plymouth Marine Laboratory.

The Met Office Central Team would also like to thank the Fresh Eyes group, Independent Review Group and Met Office Editorial Team for their valuable contributions throughout the project.

We are grateful for the support and guidance provided by the CCC Secretariat and Adaptation Committee, as well as the engagement of Government stakeholders.

We also acknowledge the valuable contributions from those who provided information through two Calls for Evidence (392 submissions) and those who contributed to the Community Review (424 reviewers) who engaged with an initial draft of the report.

Finally, we would like to express our sincere appreciation to all individuals and partners who provided in-kind contributions. Their generous provision of expertise, services and resources has significantly enhanced the quality and impact of the work, reduced costs and strengthened the overall delivery of the project. Their commitment, collaboration, and support are deeply valued.

Statements

Each chapter is authored by academic experts, supported by quality assurance and peer review from the Met Office, Science Assurance Group, Independent Review Group, Climate Change Committee Secretariat and Adaptation Committee, and Community Review.

Throughout the report we have ensured robust Quality Assurance standards to articulate clear linkages between the evidence and the Urgency scoring. This has included careful review of the content and cross-checking of references. Formal processes have involved scrutiny from the Science Assurance Group, an Independent Review Group, and the CCC Secretariat and Adaptation Committee.

This content has been created by the authors. Whilst AI tools (such as M365 Copilot) may have been used to support the literature review process and to refine the document, all outputs have been reviewed and checked by the authors and reviewers.  

Throughout the report we refer to: 

• Lead Authors: experts in their respective field accountable for producing a section of the report, drawing upon additional experts as required. 
• Contributing Authors: experts in their respective field who have provided significant knowledge, expertise, data or text for integration within a section of the report. 
• Additional Contributors: those who have provided additional support in the creation of a section of the report. This could take many forms including adding small amounts of text, editing, proof reading, creating figures or coordination of its production.  

This publication is available in PDF format at the end of the page >

Citations

The whole report is citable as: Lowe, J. A., Harrison, M. and Perks, R. J. (2026). CCRA4-IA Technical Report.

The Executive Summary is citable as:
Lowe, J. A., Harrison, M. and Perks, R. J. (2026). Executive Summary. In: CCRA4-IA Technical Report [Lowe, J. A., Harrison, M. and Perks, R. J.].

Each chapter is citable as:
Lead Authors (2026). Chapter Title. In: CCRA4-IA Technical Report [Lowe, J. A., Harrison, M. and Perks, R. J.].