Europe Heatwaves Kill 50,391 as Fossil Fuels Drive Toll

Heat waves across Europe killed an estimated 50,391 people in June, July and August 2026. Researchers attributed 32,619 of those deaths to extra heat caused by burning coal, oil and gas. Their estimate covers 854 cities; it is not a count taken directly from death certificates.

That total stands 71% above the researchers’ previous deadliest summer: in 2022, 29,480 people died. The team said the 2026 figure likely understates the toll because it leaves out a deadly May heat wave and covers cities where about 40% of Europe’s population lives.

Deaths linked to fossil fuel warming

About one-third of the deaths came during an especially intense heat wave that ran from June 17 to July 1. Temperatures then rose 9.5 degrees Fahrenheit (5.3 degrees Celsius) above normal, said study co-author Garyfallos Konstantinoudis, a biostatistician at Imperial College London.

Lead author Clair Barnes, a climate scientist at Imperial College London, said some European cities reached temperatures 21.6 F (12 C) above normal. Italy, France, Spain and Germany recorded the highest death tolls. In a separate analysis, the researchers found Rome had the highest heat death total among European capitals from 2000 to 2025.

“Much of Western and Northern Europe, our infrastructure is just not designed to cope with the sort of temperatures that we are seeing now because of the effects of human-caused warming,” Barnes said. Europe is the fastest-warming continent, she said, although the Arctic is warming faster. Europe is 4.5 F (2.5 C) hotter than in pre-industrial times.

“Just the underlying warming from human activity, from mostly the burning of fossil fuels, it's increasing all of our temperatures by what sounds like quite a small amount,” Barnes said. “For many people, it's certainly the case that that extra two-and-a-half degrees (Celsius) of warming is what's going to tip those temperatures from uncomfortable to dangerous and potentially deadly.”

Who died, and how researchers counted

More than half of those who died were 85 or older. Heat also killed more than 800 people aged 20 to 44, Konstantinoudis said.

The researchers compared computer simulations of a world without climate change against deaths recorded during the summer. They attributed the difference to global warming. Barnes said global warming’s share of heat deaths climbed from about 45% in the early 2000s to 65% now.

Heat deaths often go unreported and don’t appear on death certificates, Konstantinoudis said, so the team used statistical modeling to estimate the total. Barnes said the researchers used a mathematical equation from previously peer-reviewed studies, accounting for age and temperatures in each city compared with a localized temperature linked to the fewest deaths.

The team also checked its calculations against government estimates. For British heat waves in May and June, its method counted 2,700 excess deaths, while the United Kingdom health statistics agency estimated 2,800. Outside experts agreed with the researchers’ methods and called them state-of-the-art.

Economic cost and calls for prevention

A separate Bloomberg report put the summer heat death toll in European cities at about 50,000, describing it as the highest on record. It said heat cut European Union gross domestic product by roughly 0.17% from April through September, or close to €17 billion ($18.9 billion). The death and economic figures came from two separate studies.

“We need to prepare for the heat we cannot now avoid, with urgent investments in heat early-warning systems, equitable access to low-carbon cooling, and neighborhood buddy systems that check on and support people most at risk — while rapidly reducing the fossil fuel use driving the crisis,” said Dr. Courtney Howard, a Canadian emergency room physician and president-elect of the Canadian Medical Association, who wasn’t part of the research.

Dr. Jonathan Patz of the University of Wisconsin-Madison, who also wasn’t involved in the study, said: “We can't just be mopping up the mess on the floor without thinking about turning the faucet off. So we need prevention at different levels. We need better cooling and protecting vulnerable populations from inevitable increased frequency and extreme heat waves. But we also need to go to the root of the problem and absolutely address the burning of fossil fuels.”