Summer heat killed more than 50,000 in Europe in deadliest season on record, studies find

Climate change drove about two-thirds of the death toll, researchers estimate

By LineZotpaper

Published23 October 2026

Updated23 October 2026

Read Time2 min

Sources4 outlets

Extreme heat killed more than 50,000 people in Europe this summer, making 2026 the deadliest year on record for heat-related mortality on the continent, with climate change responsible for about two-thirds of the deaths, according to two peer-reviewed studies published in the journal Nature Health.

Two studies by researchers at Imperial College London and the London School of Hygiene & Tropical Medicine make up the first comprehensive assessment of fatalities during this year's record-breaking heat waves. They examined 854 cities across the European Union, the United Kingdom, Norway and Switzerland, home to about 40 per cent of the population of those 30 countries. Because the coverage is confined to urban areas, the full death toll including rural populations is likely higher still.

"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 lead study author Clair Barnes, an extreme weather researcher at Imperial College London. "These numbers are a stark reminder that our hotter, more extreme summers are having an increasingly severe impact on public health. Behind these statistics are real people whose lives were lost and real families who grieve for them."

The researchers estimated more than 50,000 heat-related excess deaths in the cities studied this summer, with around 32,000 of them attributable to climate change. The figure outstrips the previous records of 29,000 deaths in 2022 and 28,000 in 2003. Over the longer period from 2000 to 2025, a companion study counted 430,000 heat-related deaths, around half of them caused by climate change.

To isolate the role of global warming, the scientists compared the actual temperatures recorded in each city with a model representing a world without climate change. The method, which pairs temperature records with historical heat-mortality models, has consistently produced results that mirror official statistics later released by governments, the researchers said.

Almost a third of this summer's deaths came during Europe's late June heat wave, which smashed several temperature records. The elderly carried the heaviest burden: people aged 85 and over accounted for roughly half of the estimated deaths, said Garyfallos Konstantinoudis, a study co-author and assistant professor at Imperial College. But about 6,000 of the deaths were among people under 65, including more than 800 people aged between 20 and 44. "However, heat-related mortality was not limited to the older populations," he said.

Analysis

Why This Matters

Heat has become one of Europe's deadliest climate hazards, and 2026's toll eclipses the previous record years by tens of thousands of deaths.
The burden falls hardest on people aged 85 and over, but more than 800 deaths among adults aged 20 to 44 show the risk reaches younger working-age populations.
With climate change driving roughly two-thirds of the deaths, the findings add urgency to both emissions reduction and heat preparedness measures.

Background

Climate science has long established that global warming is making heat waves more frequent, longer and more intense. Europe, with its aging population, dense cities and large numbers of elderly residents, is among the most exposed regions. This summer's late June heat wave broke multiple temperature records across the continent, and the two new Nature Health studies are the first attempt to quantify its full human cost across major European cities. The estimates use statistical models of excess deaths above historical norms, a method the researchers say has tracked official mortality data well in previous years.

Key Perspectives

Researchers: The study team says the figures are a stark reminder that hotter summers are taking an increasingly severe toll on public health, and that their modelling approach has consistently matched official statistics released later by governments.

Public health authorities and governments: The concentration of deaths among people aged 85 and over, alongside thousands of deaths in younger adults, highlights the challenge of protecting elderly residents, outdoor workers and city populations as summers warm. The analysis gives national health systems a clearer picture of where heat plans and warning systems need to be strengthened.

Caveats: The estimates are based on statistical modelling rather than individual death records, and cover only the roughly 40 per cent of the population living in the 854 cities studied. The researchers say the full toll is therefore likely higher, and official mortality statistics will test the accuracy of their numbers.

What to Watch

Official mortality data for the summer, which the researchers say typically confirms their modelled estimates when governments release it.
Whether European countries expand heat warning systems, cooling shelters and protections for the elderly and outdoor workers before next summer.
The next heat season: after 2026 outstripped 2022 and 2003 by tens of thousands of deaths, a repeat heat wave would show whether preparedness has kept pace with a warming climate.

Sources

This summer’s heat was Europe’s deadliest on record, scientists say · Politico Europe
Heat killed ‘staggering’ 50,000 people in Europe’s cities this summer, scientists warn · World news | The Guardian
Europe’s summer heat wave killed more than 50,000 people in urban areas · Latest News from Science Magazine
Europe’s record-breaking summer heat estimated to have killed 50,000 people - The Telegraph · "site:telegraph.co.uk when:1d" - Google News

Checked

9 claims in this story checked against 1 source: 8 supported.

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SupportedExtreme heat killed more than 50,000 people in Europe this summer.Politico Europe: “Extreme heat killed more than 50,000 Europeans this summer.”
SupportedThe summer was the deadliest on record for heat in Europe.Politico Europe: “This summer’s heat was Europe’s deadliest on record, scientists say.”
Partly supportedThe summer of 2026 was the deadliest year on record for heat-related mortality across the continent.Politico Europe: “The scientists also found that this summer was the deadliest so far this century.”
SupportedClimate change was responsible for about two-thirds of the death toll.Politico Europe: “Climate change was responsible for two-thirds of the death toll.”
SupportedBarnes said, “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.”Politico Europe: ““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 study lead author Clair Barnes, an extreme weather researcher at Imperial College London.”
SupportedBarnes said, “These numbers are a stark reminder that our hotter, more extreme summers are having an increasingly severe impact on public health. Behind these statistics are real people whose lives were lost and real families who grieve for them.”Politico Europe: ““These numbers are a stark reminder that our hotter, more extreme summers are having an increasingly severe impact on public health. Behind these statistics are real people whose lives were lost and real families who grieve for them,” she added.”
SupportedThe researchers estimated more than 50,000 heat-related excess deaths in the cities studied, with around 32,000 attributable to climate change.Politico Europe: “They found that more than 50,000 heat-related excess deaths occurred in those cities this summer, with around 32,000 attributable to climate change driving up temperatures.”
SupportedThe researchers examined 854 cities in the EU, UK, Norway and Switzerland, covering about 40% of the population of those 30 countries.Politico Europe: “Scientists from Imperial College and the London School of Hygiene & Tropical Medicine examined 854 cities in the European Union, the United Kingdom, Norway and Switzerland, home to about 40% of the 30 countries’ population.”
SupportedPeople aged 85 and over accounted for roughly half of the estimated deaths.Politico Europe: “People aged 85 and over accounted for roughly half of the estimated deaths,” said Garyfallos Konstantinoudis, study co-author and assistant professor at Imperial College.”