Heat waves caused more than 6,700 deaths in Spain during the summer of 2024.

The summer of 2024 was the hottest on record in Europe, leaving a serious impact on health. A study published in Nature Medicine and led by the Barcelona Institute for Global Health (ISGlobal), a center supported by the "la Caixa" Foundation, estimates that more than 62,700 people died on the continent due to extreme heat between June 1 and September 30.

In Spain, the report puts the death toll at 6,743 , making it the country with the second highest heat-related mortality rate, behind only Italy (19,038). Despite the magnitude of the data, mortality was almost 50% lower than in 2022 (12,135 deaths), a hotter summer in Spain.

The analysis covered 654 regions in 32 European countries. After Spain, the countries with the most heat-related deaths were Germany (6,282), Greece (5,980), and Romania (4,943). In total, the study estimates more than 181,000 deaths in Europe in the summers of 2022, 2023, and 2024, two-thirds of them concentrated in the south of the continent.

Mortality rates were uneven across age and sex: in 2024, deaths among women were 46.7% higher than those among men, while mortality among those over 75 was more than three times higher than among the rest of the population.

The summer of 2024 in Spain was less extreme than in 2022 and 2023, which explains the reduction in heat-related mortality. Even so, the figures continue to place our country among the most affected in Europe, given its geographical location and the vulnerability of the Mediterranean basin to the climate crisis.

"Europe is the continent that is warming the fastest, at a rate double the global average. And within Europe, the Mediterranean has established itself as a critical hotspot for climate change, with growing impacts on health," explains Tomáš Janoš, ISGlobal researcher and first author of the study.

In addition to quantifying the impact of heat waves, the study evaluated the Forecaster.health tool, a prediction system that converts meteorological data into health alerts specific to each region and population group. According to the authors, this platform allows for anticipating the risk of extreme heat-related mortality up to a week in advance.

"The magnitude of these figures requires strengthening adaptation strategies, including a new generation of health alert systems that can save lives among the most vulnerable populations," says Joan Ballester Claramunt, principal investigator of the European EARLY-ADAPT project and senior author of the study.

Epidemiologist Usama Bilal of Drexel University (USA) believes that the work "allows for the creation of more precise alerts that take into account the context of each area—35ºC in Asturias is not the same as 35ºC in Seville."

For his part, in statements to SCM , Jesús Adrián Álvarez, actuary and doctor in Public Health, emphasizes that " these studies are a reminder of the true human cost of climate change " and that the key will be "how health systems manage to adapt to prevent avoidable deaths in future heat waves."