Brussels: A swift scientific assessment has estimated that approximately 2,300 people died across 12 European cities during the intense 10-day heatwave that gripped Western Europe, ending on July 2. The study points to extreme temperatures, particularly in Spain, where thermometers soared past 40°C (104°F), and wildfires in France, as major triggers of this deadly spell.
Researchers based their findings on historical mortality records and epidemiological models, which are commonly used in climate-related health studies. The toll reflects deaths either directly caused by heat or cases where high temperatures worsened underlying medical conditions such as cardiovascular or respiratory illnesses.
Scientists behind the analysis stressed that the actual number may be higher, as many heat-related fatalities go unrecorded, and some national authorities do not publish such statistics in real-time. The urgency of the report lies in its method peer-reviewed and rapidly deployed due to the lack of official mortality data in many parts of Europe during climate emergencies.
This deadly heatwave unfolded during what is now confirmed to be Western Europe’s hottest June on record, according to the Copernicus Climate Change Service, the European Union’s climate monitoring body. Globally, June 2025 ranks as the third-hottest June ever, surpassed only by the same month in 2023 and 2024.
Across much of Western Europe, residents endured conditions defined as "very strong heat stress," where the temperature feels like 38°C or more, often due to high humidity and poor air movement.
“In a world that’s steadily warming, we can expect heatwaves to become more frequent, more intense, and to affect wider populations,” said Samantha Burgess, Deputy Director at Copernicus. She warned that unless countries accelerate efforts to adapt and protect vulnerable populations, these climate events will continue to claim thousands of lives.
A similar study last year estimated that over 61,000 people may have died in Europe’s 2022 summer heatwaves, sparking criticism over the inadequacy of current heat-preparedness systems across the continent.
Climate experts continue to point to rising greenhouse gas emissions, mainly from fossil fuel combustion, as the driving force behind global temperature increases. As the planet’s baseline warms, the intensity of future heatwaves is expected to surge, pushing temperatures to even more dangerous extremes.
The findings serve as yet another grim reminder that the climate crisis is no longer a distant threat, but a present-day reality with deadly consequences across Europe.