Human-made global warming caused two in every three heat deaths in Europe during this year's scorching summer, according to an early analysis of mortality in 854 big cities. Researchers from Imperial College London attributed 16,500 out of 24,400 heat deaths from June to August to the extra hot weather brought on by greenhouse gases.
The rapid analysis, which has not yet been submitted for peer review, found climate breakdown made the cities 2.2C hotter on average, greatly increasing the death toll. 'The causal chain from fossil fuel burning to rising heat and increased mortality is undeniable,' said Friederike Otto, a climate scientist at Imperial College London and co-author of the report.
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 happen in homes and hospitals, where people with existing health conditions are pushed to their limits,' said Garyfallos Konstantinoudis, an epidemiologist at Imperial College London and co-author of the study. 'But heat is rarely mentioned on death certificates.'
Individual cases highlight the dangers. Manuel Ariza Serrano, a 77-year-old former councillor in La Rambla, Spain, died after collapsing during a walk in August when temperatures reached 45C. Brahim Ait El Hajjam, a 47-year-old father of four in northern Italy, died while laying concrete near Bologna in 38C heat, two days before a regional order to stop outdoor construction work in the early afternoon was set to take effect.
Konstantinoudis said the public health risk from heat was still being underestimated. 'No one would expect someone to risk their life working in torrential rain or hurricane winds. But dangerous heat is still treated too casually.' Europe's cities are better prepared than in 2003, when a heatwave killed 70,000 people, but emergency services are struggling to keep pace with rising temperatures and an ageing population.
Madeleine Thomson, an adaptation expert at Wellcome, said the data showed that 'no city in Europe is immune' to deaths from extreme heat. 'If we don't act now, the toll will rise. We must urgently phase out fossil fuels and implement policies that protect those most at risk from increasingly deadly heatwaves.'
