Professor Kopp said: “When we look at the risks of a warmer planet, we need to pay particular attention to combined extremes of heat and humidity, which are especially dangerous to human health.
Dawei Li, the study’s lead author, said: “Every bit of global warming makes hot, humid days more frequent and intense.
“In New York City, for example, the hottest, most humid day in a typical year already occurs about 11 times more frequently than it would have in the 19th century.”
According to the Met Office, climate change has made a record-breaking summer in 2018 at least 30 times more likely to occur.
The summer saw thermometers peak at temperatures of 35.3C (95.54).