The most at-risk regions in the world for high-impact heatwaves

Heatwaves are becoming more frequent under climate change and can lead to thousands of excess deaths. Adaptation to extreme weather events often occurs in response to an event, with communities learning fast following unexpectedly impactful events. Using extreme value statistics, here we show where regional temperature records are statistically likely to be exceeded, and therefore communities might be more at-risk. In 31% of regions examined, the observed daily maximum temperature record is exceptional. Climate models suggest that similar behaviour can occur in any region. In some regions, such as Afghanistan and parts of Central America, this is a particular problem - not only have they the potential for far more extreme heatwaves than experienced, but their population is growing and increasingly exposed because of limited healthcare and energy resources. We urge policy makers in vulnerable regions to consider if heat action plans are sufficient for what might come. The global risk of record-breaking heatwaves is assessed, with the most at-risk regions identified. It is shown that record-smashing events that currently appear implausible could happen anywhere as a result of climate change.

Automated summary

Heatwaves are becoming more frequent and resulting in excess deaths under climate change. Using extreme value statistics, it is shown that regional temperature records are likely to be exceeded in many regions, making them more at-risk. Certain regions like Afghanistan and parts of Central America are particularly vulnerable due to potential extreme heatwaves, population growth, and limited healthcare and energy resources. Policy makers in vulnerable regions are urged to ensure adequate heat action plans. The study concludes that record-breaking heatwaves, currently seen as implausible, could occur anywhere due to climate change.