Heat inequality: extreme climate has become the hidden killer of the poor

Heat inequality is causing thousands of unreported deaths in poor countries and communities, a leading analyst of climate impacts has warned, after global temperature reached record levels that may not have been seen in 120,000 years.

- Jonathan Watts, Isabella Kaminski

Sweltering conditions act as a stealthy killer that preys on the most economically fragile, said Friederike Otto, a co-founder of World Weather Attribution, in an appeal for the media and authorities to pay more attention to the dangers.

"Heatwaves are the deadliest type of extreme weather but they don't leave a trail of destruction or striking images of devastation. They kill poor, lonely people in rich countries, and poor people working outdoors in developing countries," said Otto, who is also a senior lecturer in climate science at the Grantham Institute of Imperial College London. "In the last 13 months, there will be thousands and thousands of stories of poor people dying in heat that will never be told."

There is growing concern about the hidden toll of heat inequality. Last month, the UN secretary-general announced a call to action on extreme heat, with a focus on care for the vulnerable and protection of workers.

"It is estimated to kill almost half a million people a year; that's about 30 times more than tropical cyclones," António Guterres said.

This followed the world's three hottest days on record on 21, 22 and 23 July. As well as passing the previous peak in datasets going back to 1940, climatologists said it was probably also the highest temperature on Earth in about 120,000 years, based on evidence from tree rings and ice cores.

It did not come without warning. Up to July, the Earth had set 13 consecutive monthly temperature records, primarily because of human burning of forests, gas, oil and coal.