Europe records 50,391 heat deaths

50,391 people died from extreme heat across Europe this summer, according to a new study published in Nature Health.

Researchers from Imperial College London modeled mortality data for 854 cities during June, July, and August. The analysis found that 32,619 of those deaths resulted from additional warming caused by burning coal, oil, and gas.

This toll represents a 71 percent increase over the previous deadliest summer in 2022, which recorded 29,480 heat-related deaths. The authors note that the current figures likely undercount the true impact because they exclude a deadly heat wave in May and cover only 40 percent of the continent's population.

Italy, France, Spain, and Germany recorded the highest number of deaths. The period between June 17 and July 1 produced approximately one-third of the fatalities, a time when temperatures ran 5.3 degrees Celsius above normal, said co-author Garyfallos Konstantinoudis, a biostatistician at Imperial College London.

More than half of the victims were aged 85 or older. However, the heat also killed more than 800 people between the ages of 20 and 44.

Lead author Clair Barnes, a climate scientist at Imperial College London, stated that some cities experienced temperatures 12 degrees Celsius above normal. Barnes explained that infrastructure in much of Western and Northern Europe was not designed for the current temperature levels driven by human-caused warming. She added that Europe is now 2.5 degrees Celsius hotter than pre-industrial times, a change that can shift conditions from uncomfortable to deadly.

To isolate the effect of climate change, the team ran computer simulations of a world without anthropogenic warming and compared the results to actual summer deaths. Barnes said the share of heat deaths attributable to global warming has risen from about 45 percent in the early 2000s to 65 percent now.

The researchers relied on statistical modeling because heat deaths are often underreported and missing from death certificates. The model accounts for age and each city's optimal temperature. They validated the results against government estimates, which generally matched. For the May and June heat waves in Britain, the model estimated 2,700 excess deaths, while the United Kingdom's health statistics agency reported 2,800.

Dr. Howard Frumkin, former director of the National Center for Environmental Health in the U.S., said the combination of hotter summers and improved attribution tools is producing higher and more reliable counts. Dr. Courtney Howard, president-elect of the Canadian Medical Association, called for investment in early-warning systems and equitable access to low-carbon cooling. Dr. Jonathan Patz of the University of Wisconsin-Madison emphasized the need to address fossil fuel burning to stop the rising death toll.