Earlier this week, the Climate Change Committee (CCC) published the Fourth Climate Change Risk Assessment - Independent Assessment (CCRA4-IA).
CCRA4-IA consists of a Met Office-led Technical Report and a CCC-led Well-Adapted UK Report. The CCRA4-IA combines up-to-date evidence on the risks of climate change with advice on the actions UK governments can take to improve climate resilience.
What is the CCRA4-IA Technical Report?
“The CCRA4-IA Technical Report brings together the latest scientific evidence on the range of climate risks facing the UK and the level of urgency required to address them,” explained Professor Jason Lowe OBE, Met Office Principal Fellow Applied & Climate Science. “Adaptation is critical to protecting the UK from the worst impacts of climate change, and an evidence-based approach to assessing the risks will help ensure the most effective action is taken.”
Underpinning the UK’s statutory Climate Change Risk Assessment required under the Climate Change Act (2008), the CCRA4‑IA Technical Report synthesises the most up‑to‑date evidence on 41 climate change risks and two opportunities, assessing their current and future magnitude and the urgency of further action across the UK. The report provides the analytical backbone that supports advice from the CCC to government and other decision‑makers.
The Technical Report plays a distinct and vital role within the CCRA4-IA: it sets out the detailed evidence, methods and justification that ensure the overall assessment is credible, transparent and scientifically robust.
Rachel Perks, Met Office Science Manager Climate Resilience, co-led the project delivery and said, “At its core, the CCRA4-IA Technical Report is about using evidence well. It provides a strong scientific foundation to support decisions government needs to make about risk and resilience. As co-lead for project delivery and a contributing author to the infrastructure chapter, I saw how combining the best available science helps clarify where the most serious risks lie, particularly across our interconnected infrastructure systems.”
A consortium of experts
One of the most significant pieces of climate risk evidence produced for the UK in recent years, one of the CCRA4-IA Technical Report’s defining strengths is the scale and diversity of collaboration behind it. The landmark report brings together expertise from across academia, the public sector, the private sector and the third sector, with lead authors from academic partners including the University of Birmingham, University of Leeds, University of Bristol, University of Exeter, University College London, University of Reading, the Centre for Ecology & Hydrology, and Plymouth Marine Laboratory, among many others.
Dr Daniel Donaldson, Deputy Head of Resilient Systems and Climate Action Research Group, University of Birmingham, was one of the lead authors. He said, “Working within the consortium as one of the lead authors for the infrastructure chapter of the CCRA4-IA Technical Report, I saw first-hand how essential cross-disciplinary collaboration is to build a clear, evidence-based understanding of climate risks for the UK.”
The partnership model ensured that each chapter was developed by subject‑matter experts with deep domain knowledge, while benefiting from cross‑cutting input through science assurance, independent review, and ‘fresh eyes’ review groups. “The combination of skills and expertise across the Met Office-led consortium has ensured that the CCRA4-IA Technical Report provides a robust evidence-base for informing adaptation policy advice,” explains Mark Harrison, Met Office Interim Associate Director Applied Science and Consultancy.
Why the Technical Report matters
The importance of the CCRA4-IA Technical Report extends well beyond publication. It provides an authoritative evidence base that will be used by policymakers, practitioners, researchers and industry to inform adaptation planning and investment decisions for years to come. The benefits of the report will continue to accrue as its evidence is applied and its methods inform future climate risk and adaptation work.
"Global warming has accelerated since the Third Climate Change Risk Assessment Technical Report, which was published in 2021, and we are on the brink of seeing a rise of 1.5°C above pre-industrial levels. We shall need to act now to adapt and build resilience to our current and future climate using the best available analysis and data," said Met Office Chief Scientist, Professor Stephen Belcher.
Crucially, the independent assessment report is designed to be evidence‑led, objective and accessible. It does not make policy recommendations; instead, it sets out what the science and evidence say about risks, opportunities and urgency, allowing others to make informed decisions. This clarity and independence are central to the credibility of the wider CCRA process.
Looking ahead
The CCRA4-IA Technical Report stands as a powerful example of what can be achieved through collaboration across institutions and disciplines. It reflects not only the depth of UK climate science, but also a shared commitment to providing clear, trusted evidence to support the UK’s response to climate change. The Well-Adapted UK Report focuses on the solutions, using the Technical Report’s evidence base to provide a guide to setting targets and measuring progress in a complex area, for use by UK Governments and other organisations.
The UK Government’s Fourth Climate Change Risk Assessment (CCRA4) is due to be laid before parliament in early 2027, with policymakers using the Independent Assessment to inform their plans for the coming years.
