As global temperatures continue to rise, extreme heat is becoming an increasingly deadly consequence of a warming planet. This past summer, Europe endured soaring temperatures and multiple heatwaves. Now, a new analysis offers a shocking estimate of the season’s toll on human life.
Scientists estimate that the heat killed more than 50,000 people across 854 European cities this summer, a substantially higher number than previous records in 2022 and 2003. In a new study, which is accepted for publication in Nature Health, the team of researchers analyzed temperature and mortality data across different cities and age groups to estimate heat-related deaths between June and August.
The authors behind the study blame “human-caused warming driven primarily by the burning of fossil fuels” for around two-thirds of the heat-related deaths over the summer.
Warming continent
Europe is the fastest-warming continent on Earth, according to the World Meteorological Organization (WMO). Since the mid-1990s, temperatures across Europe have risen by approximately 1.01 degrees Fahrenheit (0.56 degrees Celsius) per decade—more than twice the global average.
The summer of 2026 was Europe’s third-hottest summer on record, while Western Europe endured its hottest summer ever recorded, with a series of heatwaves that began in late May and persisted until the end of August. According to research by the World Weather Attribution, heatwaves cause more deaths in Europe than all other natural hazards combined.
The researchers behind the new study combined climate attribution models with data on the relationship between temperature and mortality to estimate how many people would have died with and without the effects of climate change. They looked at deaths in 854 urban areas across 30 countries and found that 50,391 of those deaths could be attributed to higher temperatures.
Nearly one-third of the deaths occurred between June 17 and July 1, when a heatwave resulted in temperatures that were 9.5 degrees Fahrenheit (5.3 degrees Celsius) above average temperatures in 1991 to 2020.
The highest mortality rate was for people ages 85 years and up, who represent around 22,500 of the total number of deaths. Younger people were also affected, with about 833 heat-related deaths among those ages 20 to 44.
An alarming new record
The recent analysis covers urban populations only, with the authors noting that it represents only about 40% of the total population and that the number of heat-related deaths across Europe could in fact be larger.
Still, the estimated death toll marks a new record for heat-related deaths in Europe. Europe’s two deadliest summers claimed an estimated 29,480 lives in 2022 and around 28,462 in 2003.
“Our analysis indicates that 2026 is likely to have been the most dangerously hot summer that Europe has experienced to date, with modelled heat-related excess deaths across these 854 cities substantially higher than in either 2003 or 2022,” the authors behind the study wrote. “Human-caused warming driven primarily by the burning of fossil fuels accounts for around two-thirds of the modelled deaths over the summer, adding a mortality burden that may be outpacing adaptation.”
