Scientific study identifies drivers of extreme mega-heatwaves

An international study published in Science Advances has identified the physical processes that create “mega-heatwaves,” which are approximately 10% more intense than standard heatwaves. Led by the Potsdam Institute for Climate Impact Research in Germany and the International Institute for Applied Systems Analysis in Austria, the research utilized machine learning and statistical analysis to explain why recent heat events have shattered local temperature records.

The study concludes that a feedback loop between soil moisture, atmospheric pressure, and temperature acts as fuel for these extreme events. High-pressure systems allow increased solar radiation to reach the Earth, heating the ground. As the soil dries out, it loses its ability to cool the surface, further driving up temperatures.

This phenomenon has been observed in various regions, including the 2022 European heatwave where the United Kingdom exceeded 40°C, and the 2021 Pacific Northwest heatwave in the United States. Other affected mid-latitude areas include southern Russia, Mongolia, northwest India, western South America, central and southern Africa, and northern Australia.