Imperial College Team Counts 50,391 Heat Deaths Across European Cities

Extreme heat in Europe this summer was linked to 50,391 deaths across 854 cities, with researchers attributing 32,619 of those deaths to warming from fossil fuel use. The study, led by Imperial College London, is set for publication in an upcoming issue of Nature Health.

The summer toll exceeded the previous record set in 2022, when the same team counted 29,480 deaths, a difference of 71 per cent. Researchers said the current figure is likely an underestimate because it excludes a heat wave in May and covers only the 854 cities studied, which are home to about 40 per cent of Europe's population. Italy, France, Spain and Germany recorded the highest numbers.

Roughly one-third of the deaths occurred between June 17 and July 1, a period when temperatures averaged 5.3 C above normal, according to Garyfallos Konstantinoudis, a biostatistician at Imperial College London and a co-author of the study. More than half of the dead were 85 or older, though more than 800 people aged 20 to 44 also died.

Clair Barnes, a climate scientist at Imperial College London and the lead author, said some cities ran 12 C above normal this summer. "Much of Western and Northern Europe, our infrastructure is just not designed to cope with the sort of temperatures that we are seeing now because of the effects of human-caused warming," she said. Barnes added that Europe is the fastest-warming continent and is now 2.5 C hotter than pre-industrial times.

To separate natural heat from warming-driven heat, the team ran simulations of a world without climate change and compared them with this summer's actual death toll. Barnes said the share of heat deaths attributable to warming has risen from about 45 per cent in the early 2000s to 65 per cent now. Because heat deaths often go unrecorded on death certificates, the researchers used statistical modelling that accounts for age and each city's optimal temperature. For Britain's May and June heat waves, the model produced 2,700 excess deaths; the United Kingdom's health statistics agency reported 2,800.

Dr. Howard Frumkin, former director of the National Center for Environmental Health in the United States, said he was not involved in the study. He said summers are getting hotter while the tools for attributing deaths to heat are becoming more accurate, producing higher and more reliable counts.

Dr. Courtney Howard, president-elect of the Canadian Medical Association, called for investment in early-warning systems, equitable access to low-carbon cooling and neighborhood buddy systems for people most at risk. Dr. Jonathan Patz of the University of Wisconsin-Madison said society cannot keep "mopping up the mess on the floor without thinking about turning the faucet off," and stressed the need to address fossil fuel burning.