Extreme temperatures kill five million a year

Most die from the cold but the balance is expected to shift with climate change

A wildfire burns in the mountains north of Lytton, British Columbia, Canada, during record high temperatures. Darryl Dyck / The Canadian Press via AP

Extreme temperatures, which are becoming increasingly common because of climate change, are responsible for five million global deaths every year, a new study has found.

Researchers said that 9.4 per cent of deaths globally between 2000 and 2019 were linked to extreme weather, with most of them connected to the cold.

The numbers who died because of extreme temperatures fell slightly over the two decades compared with previous periods but the trend is likely to reverse as the planet heats up, say researchers from Monash University in Australia and China’s Shandong University.

Global warming continues to accelerate, with the planet on track to warming of about 2.9°C above the pre-industrial average by 2100, according to estimates by the research centre Climate Action Tracker. Scientists forecast that a warming of more than 2°C would be catastrophic for life on the planet.

The study, published on Wednesday, said that 4.6 million died from extreme cold and 490,000 from the heat during a period when temperatures rose 0.26°C per decade.

The past two decades were the hottest since the pre-industrial era with the 10 warmest years on record occurring during the period.

Prof Yuming Guo, one of the authors from Monash University, said that in the long-term “climate change is expected to increase the mortality burden because hot-related mortality would be continuing to increase”.

Half of the deaths, 2.6 million, were in Asia. China on its own accounted for 1.04 million, while 1.2 million were in Africa and 835,000 in Europe, which has been hit by a series of heatwaves.

The paper, published in The Lancet Planetary Health, concluded that the fall in numbers was linked to a reduction in cold-related deaths of 0.5 per cent from 2000 to 2019, while heat-related deaths rose 0.2 per cent.

A second paper published in the same journal said that deaths from extreme heat could outstrip those linked to the cold if countries continued with high levels of damaging emissions and failed to adapt to the changing weather.

Using data from 16 countries from 1998 to 2012, the Barcelona Institute for Global Health found that extreme weather-related deaths in Europe were likely to rise in the coming years because of climate change. Mediterranean countries were likely to be the hardest hit.