Study links 32,619 Europe heat deaths to warming

Key Takeaways

The toll	The team estimates 50,391 heat-related deaths in 854 cities from June through August 2026, with a confidence range of 46,026 to 53,878.
The warming share	Of that total, 32,619 deaths, or 65 percent, are attributed to human-caused warming. The range is 26,078 to 38,237 deaths, or 53 to 73 percent.
The comparison	A rerun with the same population assumptions used for earlier summers puts 2026 at 45,492 deaths, which the authors call around 50 percent above 2022 or 2003.
The limit	The cities hold about 40 percent of the population in 30 countries. May 21 to May 31 adds 1,508 deaths that are outside the summer total.

A team led by Clair Barnes at Imperial College London estimates 50,391 heat-related deaths in 854 European cities from June through August 2026, including 32,619 from human-caused warming. The Europe heat deaths 2026 report, issued Friday, Oct. 23, has been accepted by the journal Nature Health.

What the Europe heat deaths 2026 count includes

The report covers 854 cities in 30 countries, the EU-27 plus the United Kingdom, Switzerland, and Norway, with a combined population of 172,717,680. Barnes, at Imperial's Centre for Environmental Policy, wrote it with colleagues at Imperial, the London School of Hygiene & Tropical Medicine, the University of Copenhagen, and the University of Bern. The deaths are modelled excess deaths, not a tally of certificates that list heat as the cause.

The central estimate is 50,391 deaths, with a 95 percent range of 46,026 to 53,878. The authors attribute 32,619 of them to anthropogenic climate change, 65 percent of the burden, with ranges of 26,078 to 38,237 deaths and 53 to 73 percent. People 85 or older account for 22,502 deaths, just under half the total. The 20-to-44 age group accounts for about 833.

The Associated Press, in a story NPR published on Friday, Oct. 23, said co-author Garyfallos Konstantinoudis put the share of deaths at age 85 or older at more than half. The report's central figure for that age group is 22,502 of 50,391. Almost a third of the summer deaths fell between June 17 and July 1, when city temperatures averaged 5.3 degrees Celsius above the 1991-2020 mean. In that spell, the share tied to human-caused warming was 57 percent, because the authors say the heat would have been dangerous even without the warming.

Where the modelled deaths were highest

Italy, France, Spain, and Germany have the largest city tolls in the report's country table. The age-standardized rates are highest in Malta, Italy, Hungary, and Croatia. Southern Europe's attributable share is 69 percent. Malta is the exception on attribution: its warming share is so uncertain that the range crosses zero.

• Italy: 13,303 deaths (11,829 to 14,965), of which 8,772 are attributed to human-caused warming.
• France: 7,268 (6,228 to 8,243), of which 4,661 are attributed to warming.
• Spain: 6,824 (5,744 to 7,984), of which 5,227 are attributed to warming.
• Germany: 6,340 (5,367 to 7,136), of which 3,685 are attributed to warming.
• United Kingdom: 4,354 (3,491 to 5,227), of which 2,535 are attributed to warming.

"In some sense, the absolute numbers of the heat-related deaths estimated across the 854 urban areas are indeed staggering," Malcolm Mistry, a co-author at the London School of Hygiene & Tropical Medicine, told the Guardian. "But perhaps what is even more alarming is the proportion of these deaths that we attribute to anthropogenic climate change."

How 2026 compares with 2022

The same group's Nature Health paper, published Wednesday, Oct. 14, 2026, estimated 29,480 heat-related deaths in these cities in summer 2022 and 28,462 in summer 2003. Set against that 2022 figure, the new total of 50,391 is about 71 percent higher, the comparison the Associated Press reported. The new report also says 2026 is almost double its estimate for summer 2025, which was 24,572.

Those headline totals do not all use the same population file. When the authors rerun 2026 with the 2000-2019 population and death rates used in the earlier paper, they get 45,492 deaths, with a range of 41,429 to 48,719. They call that around 50 percent higher than 2022 or 2003. On that matched basis, deaths attributed to human-caused warming are 29,330. The Guardian described the summer toll as nearly twice the toll in each of those two earlier summers.

Across 2000 to 2025, the Oct. 14 paper estimates 430,365 heat-related deaths in the same cities, with the share tied to human-caused warming rising from 39 percent in 2000 to 68 percent in 2025. The new report puts summer 2026 at 65 percent. It also says Europe in 2026 was about 2.5 degrees Celsius warmer than it would have been without human-caused warming, and that the 854 cities ran about 2.4 degrees above the 1991-2020 summer average. Some countries had days as much as 12 degrees above that average.

What government counts show

The authors compare their model with near-real-time counts from health agencies and say the methods differ too much for a straight match. Official figures often use a baseline that already includes some human-caused warming. The report still calls the official numbers broadly consistent once the cities' partial coverage is taken into account.

• Sante Publique France: 5,764 heat-related excess deaths from June 17 to July 2.
• UK Health Security Agency: 2,124 heat-related excess deaths in England and Wales from June 21 to June 28.
• Spain's Mortality Monitoring System: 5,123 heat-related excess deaths from June through August.
• Germany's Robert Koch Institute: 16,000 heat-related excess deaths from April 6 to Sept. 6.

The summer total leaves out May 21 to May 31, when the authors estimate 1,508 further heat-related deaths. The city set is about 40 percent of the population of the 30 countries, and the authors say the Europe-wide toll is larger and cannot be scaled up from this sample. The model also uses daily mean temperature only. The authors say early-season timing, humidity, and hot nights may mean the true toll is higher than the model.