A severe heatwave that recently swept across 12 European cities has resulted in approximately 2,300 heat-related deaths, with 1,500 of those fatalities directly linked to climate change, according to a new rapid analysis by UK scientists. The study, conducted by researchers at Imperial College London and the London School of Hygiene and Tropical Medicine, focused on the 10-day period ending July 2, during which temperatures soared above 40°C in parts of Spain and devastating wildfires broke out in France. “Climate change has made it significantly hotter than it would have been, which in turn makes it a lot more dangerous,” said Dr Ben Clarke, a researcher at Imperial College London. The study found that climate change increased temperatures during the heatwave by up to 4°C in cities such as Barcelona, Madrid, London, and Milan. The researchers used established epidemiological models and historical mortality data to estimate the death toll—figures that include deaths where extreme heat worsened existing health conditions. Many heat-related deaths are not officially documented, and some governments do not publicly release such data, prompting the need for independent rapid assessments.
The findings come as the EU’s Copernicus Climate Change Service confirmed that last month was the planet’s third-hottest June on record, with Western Europe recording its warmest June ever. Much of the region experienced “very strong heat stress,” defined by conditions that feel like 38°C or more. “In a warming world, heatwaves are likely to become more frequent, more intense and impact more people across Europe,” warned Samantha Burgess, strategic lead for climate at Copernicus. This alarming event echoes previous reports from 2023, when researchers estimated that up to 61,000 people may have died due to Europe’s record-breaking 2022 heatwaves. The data underlines growing concerns that current heat preparedness measures remain dangerously inadequate. The root cause, scientists stress, is the accumulation of greenhouse gases—primarily from fossil fuel combustion—which has steadily increased Earth’s average temperature. As the climate warms, heatwaves are not just becoming more common but are reaching new extremes, posing escalating threats to human health and survival.