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,” added Professor Rowan Sutton, Met Office, UK. 

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.