Europe will record a record number of heat deaths this year with the estimate that over 50,000 people have died in urban areas during Europe’s sweltering summer, with climate change responsible for two thirds.

The modelled figure is substantially higher than the previous worst years of 2003 and 2022 as Europe’s summer temperatures grow hotter.

Scientists from Imperial College London and the London School of Hygiene & Tropical Medicine looked at 854 urban areas that make up about 40% of the population of the thirty countries studied. They found more than 50,000 excess heat deaths are likely to have occurred in urban areas during the summer of 2026 across 27 EU Countries, the UK, Norway and Switzerland with climate change – primarily from the burning of fossil fuels – estimated to be responsible for about two thirds of them.

Using temperature records and modelling built on the historical relationship between heat and mortality, they were able to estimate the heat-related excess deaths expected to have occurred in each urban area during the summers of 2000 to 2026.

By comparing the temperatures that actually occurred in each urban area with those that would have been expected without the addition of greenhouse gases, the scientists were able to estimate the additional deaths caused by climate change. The season was characterised by a succession of extreme heatwaves, particularly in western Europe, with severe impacts recorded on public health.

Western Europe experienced the highest heat anomaly with temperatures for the summer as a whole about 2.9°C above the 1991-2020 average, though some days exceeded it by as much as 12°C.

Key findings included:

• Highest on record: The modelled urban area mortality toll for this year’s summer is the highest in the 26 years since 2000, far in excess of the next highest in 2022 (about 29,000) and 2003 (about 28,000).
• Late June especially severe: Almost a third of all the deaths are estimated to have occurred during the period June 17 – July 1 2026 when daily mean temperatures across the entire region were over 5°C above the 1991-2020 average.
• Worst impacted regions: Southern and western Europe experienced the hottest temperatures as well as the highest estimated mortality rates, but thousands of deaths were also estimated in urban regions of typically cooler northern European countries such as the UK (about 4,500).
• Not just the elderly: While heat-related death typically impacts those who are older, an estimated 6,000 people under the age of 65 are thought to have died across the urban areas analysed as a result of the heat during summer 2026.
• Climate change role growing: As fossil-fuel driven climate change has pushed temperatures higher, the proportion of deaths attributable to climate change has grown too. Earlier in the century it was estimated to be responsible for about 40%, but in 2026 it has grown to about two thirds of heat-related deaths.

Dr Clair Barnes, Extreme Weather and Climate Change Researcher at the Centre for Environmental Policy, Imperial College London 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. 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. “It is yet another reminder both of the imperative of rolling out targeted interventions to protect those who are most vulnerable to this increasingly extreme heat, and of the growing need to rapidly transition away from fossil fuels to slow the pace of change and limit future warming.”

Dr Pierre Masselot, Assistant Professor, Statistician and Epidemiologist, London School of Hygiene & Tropical Medicine said: “This summer has been another dramatic reminder that climate change is everybody’s problem. It is not just hot regions that are suffering anymore with some parts of Western and Northern Europe experiencing extreme heat and historically high health burden. And the whole population is affected, as shown by the significant death toll among younger age groups. “It is becoming increasingly clear our cities are poorly adapted to rising heat, and it is critical we improve our efforts towards adaptation. This means cooling the cities through more green spaces and less pollution and providing health care for affected populations.”

Commenting on the studies’ results Ruth Fuller, WWF’s Chief Climate Advisor, said: “This new evidence shows in stark terms that heatwaves are a silent killer and there can be no clearer signal that we urgently need to tackle the root causes of the climate crisis. There is no room for delay or complacency, every fraction of a degree means greater risks both to human life and the environments we depend upon.

“With COP 31 just around the corner governments have the opportunity to act decisively to end our reliance on fossil fuels, speed up the transition to clean energy and restore nature at scale.”