Athens among cities hit hardest by climate-linked heat deaths

New research shows that Athens is one of the European cities hardest hit by heat-related deaths, as record-breaking summer temperatures continue to take a toll across the continent. Scientists are warning that climate change is directly responsible for a sharp rise in excess deaths linked to extreme heat.

A recent study by Imperial College London and the London School of Hygiene & Tropical Medicine found that 24,400 people died due to extreme heat between June and August 2025 in 854 cities across Europe. Of those, 68% — or 16,500 deaths — could have been avoided if not for human-induced climate change.

In Greece, the study recorded 808 heat-related deaths, with a staggering 630 in Athens alone. According to researchers, Athens ranks second among European capitals with the highest excess mortality due to high temperatures, following Rome and ahead of Bucharest.

“The main reason Athens ranks so high is the exceptionally high temperatures this summer,” said Garyfallos Konstantinoudis, a biostatistics and epidemiology expert at Imperial College London. He also pointed to air pollution, limited green spaces, and low public awareness as aggravating factors.

Across 14 Greek cities, the effects varied:

Thessaloniki recorded 59 heat-related deaths, with 43 attributed to climate change.

Patra saw 39 excess deaths.

Katerini had the highest percentage of deaths linked to climate change.

High impacts were also noted in Hania and Kalamata.

The most affected were older adults, with 85% of excess deaths occurring among those aged 65 and over. The study also highlights growing risks for people with chronic illnesses, and for workers in construction, transport, and tourism who are exposed to high outdoor temperatures.

One of the most dangerous periods was during the Balkan heatwave in late July, which coincided with devastating wildfires. During that week, the study found an average of 10 excess deaths per million people per day.

“These findings make it clear: our environmental choices have real consequences on human lives,” Konstantinoudis said. He added that even a 2°C rise in global temperatures could put 163 million Europeans at risk from extreme summer heat — almost double the current number.

The researchers are urging governments to take immediate action to adapt cities, protect vulnerable populations, and mitigate further climate change.