Figures show that during this summer's heatwaves in western Europe, over 20,000 people perished in temperatures that would have been virtually unimaginable without a climate breakdown.

According to scientists, an examination of excess mortality—the discrepancy between the actual number of fatalities and those predicted by historical trends—shows the dangers posed by global warming brought on by climate change.

Summer heat waves caused temperatures to exceed 40°C (104F) in London, 42°C in some parts of south-west France, and 44°C in Seville and Córdoba, Spain, setting records. Without the climate crisis, the World Weather Attribution group of scientists concluded that such high temperatures would have been "virtually impossible".

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In England and Wales, 3,271 excess deaths were recorded between June 1 and September 7, according to the Office for National Statistics – 6.2% higher than the five-year average.

Although the analysis does not estimate specifically how many deaths were caused by heat, the number of deaths was higher on average for heat-period days than non-heat-period days. Deaths in Covid-19 were not included.

There were 10,420 excess deaths reported in France during the summer months, according to data released by Santé Publique France, the government health agency.

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One in four of these deaths, or 2,816, happened during one of the three intense heat waves that hit the country. The excess deaths were 20% higher in regions where extreme temperature red alerts had been issued.

The state-backed Carlos III Health Institute in Spain estimates that there were 4,655 heat-attributable deaths between June and August.

Moreover, the Robert Koch Institute, the German government health agency, estimates that 4,500 people died in the country during the summer months specifically due to extreme temperatures.