Imperial College study: 50,391 Europeans died in record heat

A new study estimates that extreme heat killed 50,391 people across Europe this summer. The research, conducted by scientists at Imperial College London, finds that 65% of those deaths were driven by human-caused climate change.

The team analyzed data from 854 European cities during heat waves in June, July, and August. They determined that 32,619 deaths resulted specifically from the additional heat generated by burning coal, oil, and gas. These figures represent a 71% increase over the 29,480 deaths recorded in 2022, the previous deadliest summer.

The highest tolls occurred in Italy, France, Spain, and Germany. The period from June 17 to July 1 accounted for one-third of the total deaths, a time when temperatures averaged 5.3 C above normal. Garyfallos Konstantinoudis, a biostatistician at Imperial College London, noted that while more than half of the victims were aged 85 or older, the heat also claimed more than 800 lives among people aged 20 to 44.

Lead author Clair Barnes, a climate scientist at Imperial College London, stated that Europe is now 2.5 C hotter than in pre-industrial times. She explained that infrastructure in much of Western and Northern Europe was not designed for current temperatures. Barnes said this extra warming can tip conditions from uncomfortable to deadly.

To isolate the impact of climate change, the researchers used computer simulations to model a world without global warming. They compared those results to actual mortality data. This method showed that the share of heat deaths attributable to warming has risen from 45% in the early 2000s to 65% today.

The study relies on statistical modeling because heat deaths are often not listed on death certificates. The model accounts for age and each city's optimal temperature, the point where mortality is lowest. The authors note the findings are likely an underestimate because they exclude a deadly May heat wave and cover only 40% of Europe's population. The results will be published in an upcoming issue of Nature Health.

The study's methods were reviewed by outside experts. Dr. Howard Frumkin, former director of the National Center for Environmental Health in the U.S., said the tools for attributing deaths to heat are becoming more accurate as summers get hotter. Other experts, including Dr. Courtney Howard of the Canadian Medical Association, urged for better early-warning systems and access to low-carbon cooling alongside emission cuts.