The authors – led by the Met Office’s Professor Rowan Sutton and Professor Peter Stott – are calling for a global assessment of avoidable climate change risks to help governments and citizens understand the urgency of reducing greenhouse gas emissions.

Without accelerated global action, the consequences of climate change impacts will be increasingly severe, affecting millions of people and potentially undermining global stability.  But despite the huge consequences of climate change and how wide-reaching the risks are, no internationally coordinated and mandated global risk analysis has been conducted.

World unprepared

Professor Rowan Sutton – one of two senior commentary authors and Director of the Met Office Hadley Centre – said: “Despite clear scientific evidence and repeated warnings, the world remains unprepared for the scale and complexity of these challenges.

“Humanity still has the opportunity to avoid the worst impacts of climate change and shape a more prosperous, liveable future. A global assessment of avoidable climate change risks would enable political leaders and citizens to fully understand what is at stake and motivate us all to seize that opportunity - while we still have it.”

A series of global scientific reports – such as those produced by the IPCC – have helped to demonstrate many impacts of climate change, but these are science assessments rather than risk assessments.  The absence of a global risk assessment makes it difficult for governments, businesses, and communities to understand the full scale of the threat, prioritise resources, and plan effective mitigation responses.

The impacts of rising temperatures, extreme weather events, sea level rise, and shifting climate patterns are already being felt in every region. Looking to the future, climate  risks threaten food and water security, health, infrastructure, and economic development.

To put this into perspective, policymakers might realise that sea level rise requires more spending on flood defences, but they may not be aware that parts of a large city, such as London or New York, may have to be abandoned. Equally, they may be aware that more people will die in heatwaves in a hotter climate yet be unprepared for mass casualties if tens of thousands of people in one region were to die in conditions exceeding the limits of human tolerance.

Clear picture of the outcomes

A thorough global risk assessment would provide an authoritative overview of the most significant climate risks, their potential impacts, and the likelihood of disastrous outcomes. Crucially, a risk assessment does not provide a counsel of despair. Instead, it provides a clear picture of the outcomes that societies can still choose to avoid. A global climate change risk assessment would support the development of timely measures for climate change mitigation and highlight the extent of human agency.  

Rowan Sutton added: “Developing a comprehensive global climate risk assessment is not without its difficulties. The complexity of climate science, the diversity of regional impacts, the need for diverse expertise, and the rapidly evolving nature of the risks all present significant obstacles. In addition, political, economic, and data-sharing barriers have so far hindered the creation of a unified framework that can be updated regularly and accepted internationally.”

Avoidable climate change risks

Professor Peter Stott – the paper’s other leading author - is a climate scientist at the Met Office and the University of Exeter. He said: “The world stands at a crossroads in global efforts to reduce emissions. Bridging the current gap in global risk assessment is an urgent priority. An internationally mandated transparent assessment of avoidable climate change risks is essential to make clear the scale of the risks and the opportunity we have to avoid the worst case scenarios  and safeguard our shared future. The time for this is now.”

The cohort of authors includes:

Peter A. Stott, Science Fellow at Met Office Hadley Centre and Professor of Detection and Attribution at University of Exeter, Exeter, UK.

Y. T. Eunice Lo, Senior Research Fellow in Climate Change and Health at University of Bristol, Bristol, UK.

John H. Marsham, Professor of Atmospheric Science at University of Leeds, Leeds, UK.

David Obura, Director, CORDIO East Africa, Kenya ,

Tom H. Oliver, Professor of Applied Ecology at University of Reading, Reading, UK. 

Matthew D. Palmer, Science Fellow at Met Office Hadley Centre and Associate Professor in Climate Science at University of Bristol, Bristol, UK.

Nicola Ranger is Executive Director of Earth Capital Nexus and Professor in Practice at the London School of Economics, London, UK.

Simon Sharpe, Managing Director of S-Curve Economics CIC, London, UK.

Rowan Sutton, Director of Met Office Hadley Centre and Professor of Climate Science at the University of Reading, Reading, UK.

The list of co-signatories include:

Andrew Challinor, Professor of Climate Impacts at University of Leeds, Leeds, UK.

Pete Falloon, Science Lead for Food Security at Met Office and Professor of Climate Resilient Food Systems at University of Bristol, Bristol, UK.

Jason Lowe, Deputy Director of Met Office Hadley Centre and Professor in Interdisciplinary Climate Research at University of Leeds, Leeds, UK.

Dann Mitchell, Professor of Climate Science, University of Bristol, Bristol, UK.

James Savage is Head of Flood Modelling at Fathom, Bristol, UK.

Dan Williams, Head of Knowledge Integration at Met Office, Exeter, UK.