Over 50,000 people are likely to have died from heat in European cities and towns this summer, with human-caused climate change responsible for about 65 per cent of these deaths, according to estimates from two scientific studies.The deaths, classified as “excess deaths”, are estimated to have occurred across 854 European urban areas between June and August. Excess deaths refer to deaths above the number expected in a population over a given period.The findings come from two studies by scientists from Imperial College London and the London School of Hygiene and Tropical Medicine.The researchers used temperature data and climate models to compare summer temperatures in today’s climate, with about 1.4 degrees Celsius of global warming, against those in a cooler, pre-industrial world. They then drew on previous research to estimate the impact of the temperature changes on mortality.One study, examining heat-related mortality in European cities between 2000 and 2025, was published in Nature Health. The second, which estimates the impact of the 2026 summer, has been accepted for publication in the same journal.Europe’s record-breaking summerEurope experienced a series of extreme heatwaves this summer. It was the continent’s third-hottest summer on record and the hottest ever recorded in Western Europe.Clair Barnes, lead author of both studies, said Europe is now the fastest-warming continent, with summer temperatures, on average, 2.5 degrees hotter than they would have been without human-caused warming.Story continues below this adAlso Read | Brace for more heat: Worst of El Niño yet to come, peak likely in DecemberAccording to the researcher in extreme weather and climate change at the Centre for Environmental Policy, Imperial College London, burning fossil fuels primarily drives the warming.During a virtual press briefing, Barnes was asked whether El Niño had contributed to the extreme heat. She said the phenomenon has historically had little influence on European summers and that the studies did not examine its role.Italy records highest tollThe estimated toll of 50,391 deaths is substantially higher than that recorded during previous severe European summers. In 2022, heat was estimated to have caused 29,500 excess deaths, while the corresponding figure for 2023 was about 28,500.Italy recorded the highest estimated toll this summer, at 13,303 deaths, followed by France (7,268), Spain (6,824), Germany (6,340) and the United Kingdom (4,354).Story continues below this adOpinion | Europe must rethink how it will live with heatRelative to population, Malta, Italy, Hungary and Croatia were among the worst affected. People aged 85 and above accounted for the largest share of deaths. However, the researchers also estimated that about 6,000 people under the age of 65 died from heat.Nearly a third of the estimated deaths occurred during an intense heatwave between June 17 and July 1, when temperatures averaged 5.3 degrees above the recent historical average.How heat affects the bodyHeat places the body under considerable stress, particularly the cardiovascular and metabolic systems, said Professor Andrew Hartle, Professor of Practice in Anaesthesia at Imperial College London and an intensive care consultant at Imperial College Healthcare NHS Trust.Also Read | ‘Postcard from future’: Super El Niño may trigger 15,800 excess heat deaths in India“Most people compensate for getting hot by increasing blood flow to their skin and sweating, but those mechanisms require energy, and they are limited,” he said.Story continues below this adHartle said when people get dehydrated, the strain on the cardiovascular and kidney systems, in particular, increases. People with existing illnesses can find it particularly difficult to regulate their body temperature under these conditions, causing their body temperature to rise, he added.