Two in three heat deaths in Europe this summer are linked to climate change. The costs of this year’s heat waves, droughts, and floods could rise to more than €120 billion in 2029.

Now: 43 billion euros

The extreme weather of this year’s summer could cost the European Union €43 billion in damage to buildings and crops as well as a loss of productivity. This is evident from a recent study into the consequences of the heat waves, droughts, and floods between June and August 2025. The study was carried out by experts from the University of Mannheim and the European Central Bank.

Heat leads to productivity losses by outdoor workers, for example. Droughts affect agriculture, and floods damage infrastructure and buildings, and disrupt supply chains. Southern Europe was hit hardest by the extreme heat of this year’s summer. The estimated losses for Italy, for example, are €11.9 billion.

2029: more than 120 billion euros

In the long term, the costs of this year’s extreme summer weather events will rise to much higher amounts, the experts project. By 2029, this year’s heatwaves, droughts, and floods could cost the European Union more than €120 billion. France, Spain, and Italy were some of the worst affected countries, each facing over €10 billion of losses this year. These losses could triple by 2029.

In fact these figures are an underestimate, as they do not include the costs of a number of impacts, including wildfires. For example, a previous study showed that the economic damage of wildfires in Southern Europe is up to €21 billion per season, on average.

Two in three heat deaths

Human-made global warming ‘caused two in three heat deaths in Europe this summer’, researchers from Imperial College London concluded from a first assessment of the people who died this summer, Europe’s fourth warmest summer on record. The assessment is a rapid analysis in the World Weather Attribution series and has not yet been submitted for peer review.

They analysed excess mortality in 854 big cities in Europe, from Southern Europe to Scandinavia. From June to August, 24,400 people died from heat. The scientists compared mortality in the summer of 2025 with mortality that would have occurred in a hypothetical world without any climate change, by analysing relationships between temperature and death. Climate change made the cities by up to 3.6°C hotter this year’s summer. The researchers attributed 16,500 heat deaths to this extra heat brought on by climate change.

The death toll from climate change was particularly high in Rome, with 835 additional heat deaths, and in Athens (630), Paris (409), Madrid (387), Bucharest (360), and London (315).

Older people hit hardest

Older people were hit hardest, with 85% of the dead over the age of 65, and 41% over the age of 85. The vast majority of heat deaths were people with existing health conditions.

The researchers warn the result is only a snapshot of the death toll linked to extreme heat as the cities studied represent about 30% of Europe’s population. The true death toll is almost certainly higher. More than 60,000 people were likely killed by extreme heat in Europe in the summer of 2022, and more than 47,000 people in 2023, previous studies have shown.

Sources:

• Usman et al. (2025). European Economic Review 178.
• Imperial College London (2025). Climate change behind 16,500 summer heat deaths in 854 European cities.