‘Worst on record’: Brutal summer heat wave killed more than 50,000 in Europe’s cities

More than 50,000 people are estimated to have died across Europe’s cities during the brutal heat waves that roiled the continent this summer — making this year’s heat the region’s deadliest on record, according to a new analysis.

About two-thirds of the deaths, more than 32,600, are directly attributed to climate change, driven by fossil fuel pollution, according to the findings, published in two peer-reviewed papers in the journal Nature Health.

“I think we can be quite confident in stating that the summer of 2026 is likely to have been the worst on record for heat-related mortality across much of Europe,” said Clair Barnes, an author on the reports and an extreme weather and climate change researcher at Imperial College London.

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This stark death toll is revealed just weeks before international leaders gather in Turkey for the annual UN climate talks, and days after a UN report warned the world’s chance of limiting global warming to 1.5 degrees Celsius above pre-industrial levels has now vanished.

“We’re well off-track to limit the worst consequences of climate change, and governments need to realize that without faster action and coordination, things will only get worse,” Barnes said.

Europe is the fastest-warming continent and extreme heat, the deadliest form of extreme weather, is already becoming unbearable. Unprecedented high temperatures scorched the continent from late May until the end of August this year.

It was western Europe’s hottest summer on record, with temperatures about 2.9 degrees Celsius (5.2 Fahrenheit) above the 1991-2020 average. Individual days, however, saw much larger anomalies, with temperatures more than 12 degrees Celsius (21.6 Fahrenheit) higher than usual in some countries.

A tourist attempts to cool down near the Colosseum during a heatwave in Rome, Italy, on June 20.
Guglielmo Mangiapane/Reuters

To calculate the death toll, scientists compared the temperatures in 854 cities across 30 European countries this summer with those that would have been expected in a world without climate change.

They then used peer-reviewed research on the relationship between high temperatures and daily deaths to model the likely number of heat-related deaths between the start of June and the end of August. It’s a method that has been found to produce death toll estimates broadly in line with those later produced by national health authorities, the scientists said.

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They estimated a total of 50,391 heat-related deaths across the cities, which make up about 40% of the population of the countries studied. The death toll is the highest for 26 years and substantially higher than that of previous major European heat waves in 2022 and 2003, the researchers found.

Southern and western Europe were worst affected, but typically cooler northern regions, including the UK, also experienced thousands of deaths.

The highest death rates were among people 85 or older, but heat can affect anyone, and more than 800 people between the ages of 20 and 44 died from heat-related reasons, according to the findings.

This summer is “likely to have been the most dangerously hot summer that Europe has experienced to date,” the report concludes.

The scientists also found the role of climate change in heat deaths is becoming more pronounced. Earlier this century, fossil fuel pollution was responsible for about 40% of heat deaths compared to around two-thirds today.

Raquel Nunes, an associate professor in health and environment at the University of Warwick, who was not involved in the research, said the findings contribute to “growing evidence of how deadly extreme heat can be, despite being described as a ‘silent killer’ due to its impacts not always being immediately visible.”

One of the most concerning aspects was that the death toll was also high among younger people, with thousands under 65 estimated to have died, Nunes added.

“Until we kick the fossil fuel habit, we will continue to see increasingly hot and dangerous summers,” Barnes said. And that means even deadlier summers on the horizon.

“These numbers are a stark reminder that our hotter, more extreme summers are having an increasingly severe impact on public health,” she added. “Behind these statistics are real people whose lives were lost and real families who grieve for them.”