Study: Climate Change Fueled 50,000 Heat-Related Deaths Across Europe

Europe’s Summer Heat Crisis: Climate Change Linked to More Than 32,000 Deaths, Study Says

Climate change contributed to more than 32,000 heat-related deaths across Europe this summer, accounting for nearly two-thirds of an estimated 50,391 fatalities linked to high temperatures, according to a new study.

The research examined heat-related mortality in 854 European cities during heat waves in June, July and August. Published findings scheduled for an upcoming issue of Nature Health indicate that the additional heat caused by human-driven climate change, largely through the burning of coal, oil and gas, was responsible for an estimated 32,619 deaths.

The overall death toll was 71% higher than the previous summer record of 29,480 deaths in 2022, according to the researchers. They warned that the figures could underestimate the true impact because the analysis did not include a deadly heat wave in May and covered cities representing only around 40% of Europe’s population.

Extreme Heat Waves Drive Rising Death Toll

Approximately one-third of the estimated deaths occurred between June 17 and July 1, during a particularly severe heat wave when temperatures were 5.3 degrees Celsius (9.5 degrees Fahrenheit) above normal, said study co-author Garyfallos Konstantinoudis, a biostatistician at Imperial College London.

Lead researcher Clair Barnes, a climate scientist at the same institution, said much of Western and Northern Europe lacked the infrastructure needed to cope with the extreme temperatures experienced this summer. Some cities recorded temperatures as much as 12 degrees Celsius (21.6 degrees Fahrenheit) above normal.

Italy, France, Spain and Germany recorded the highest numbers of heat-related deaths, the study found. A separate analysis by the same research team found that Rome had the highest cumulative heat-related death toll among European capitals between 2000 and 2025.

Barnes noted that Europe is the fastest-warming continent, while the Arctic is warming at an even faster rate. European temperatures have risen approximately 2.5 degrees Celsius (4.5 degrees Fahrenheit) above pre-industrial levels.

She explained that even a relatively small increase in average temperatures can push extreme heat from uncomfortable to dangerous, particularly for people already vulnerable to high temperatures.

Older People Face the Greatest Risk

People aged 85 and above accounted for more than half of the estimated heat-related deaths this summer. However, the impact extended to younger adults as well, with more than 800 deaths recorded among people aged 20 to 44, Konstantinoudis said.

To determine the role of climate change, researchers compared computer simulations of a world without human-induced warming with estimates based on the temperatures experienced this summer. The difference helped them calculate the additional deaths attributable to climate change.

According to Barnes, the proportion of heat-related deaths linked to global warming has increased from approximately 45% in the early 2000s to around 65% today.

Dr Howard Frumkin, former director of the US National Center for Environmental Health, who was not involved in the research, said rising summer temperatures and improvements in scientific analysis were producing increasingly accurate estimates of heat-related mortality.

Why Heat-Related Deaths Are Often Underestimated

The researchers used statistical modelling to calculate the overall death toll because heat is frequently underreported as a contributing cause of death and may not appear explicitly on death certificates.

Their method, which has been used in previous peer-reviewed studies, accounted for age groups and local temperature patterns across all 854 cities. Researchers estimated each city’s temperature associated with the lowest mortality and calculated excess deaths when temperatures moved above or below that level.

The team also compared its estimates with government figures. For heat waves affecting Britain in May and June, the researchers calculated approximately 2,700 excess deaths, compared with around 2,800 reported by the UK’s health statistics agency, Konstantinoudis said.

• Several independent experts praised the methodology used in the study.
• Experts Urge Better Heat Protection and Faster Emissions Cuts

Researchers and public-health specialists say governments must strengthen preparations for extreme heat while reducing the emissions responsible for global warming.

Dr Courtney Howard, a Canadian emergency physician and president-elect of the Canadian Medical Association, who was not involved in the study, called for investment in heat early-warning systems, equitable access to low-carbon cooling and neighbourhood support networks to check on people at greatest risk.

She also stressed the need to reduce fossil fuel consumption rapidly to limit further warming.

Dr Jonathan Patz, a professor of health and the environment at the University of Wisconsin-Madison, said adapting to rising temperatures was necessary but insufficient. He advocated improving cooling infrastructure and protecting vulnerable populations while tackling the underlying causes of climate change.

The findings highlight the growing public-health consequences of extreme heat and the importance of combining immediate protective measures with long-term efforts to reduce greenhouse gas emissions.