The climate crisis made the record drought across the northern hemisphere this summer at least 20 times more likely, scientists have calculated. Without human-caused global heating, the event would have been expected only once every four centuries.

The drought hit crop production and power supplies, exacerbating the food and energy crises already sparked by Russia’s war in Ukraine. Droughts will become even more severe and more frequent unless the burning of fossil fuels is phased out, the researchers warned.

The dry conditions, assessed using data on soil moisture, largely resulted from the heatwaves that struck across North America, Europe and Asia, with lower rainfall relatively less important. The scientists said a summer as hot as that of 2022 would have been “virtually impossible” without global heating and in Europe alone there were 24,000 heat-related fatalities.