New York, June 20 (IANS): Nearly 75 per cent of the world’s population will be affected by deadly heatwaves by 2100 if carbon gas emissions continue to rise at current rates, says a study. Currently, about 30 per cent of the world’s human population is exposed to such deadly conditions each year, according to the researchers. Even if emissions are aggressively reduced, the per cent of the world’s human population affected is expected to reach 48 per cent, said the study published in the journal Nature Climate Change.
“We are running out of choices for the future,” said Camilo Mora, Associate Professor of Geography at the University of Hawaii at Manoa in the US and lead author of the study. “For heatwaves, our options are now between bad or terrible. Many people around the world are already paying the ultimate price of heatwaves, and while models suggest that this is likely to continue, it could be much worse if emissions are not considerably reduced,” Mora said.
The human body can only function within a narrow range of core body temperatures around 37 degrees Celsius.
“Heatwaves pose a considerable risk to human life because hot weather, aggravated with high humidity, can raise body temperature, leading to life threatening conditions,” Mora added. A team of researchers led by Mora conducted an extensive review and found over 1,900 cases of locations worldwide where high ambient temperatures have killed people since 1980.
By analysing the climatic conditions of 783 lethal heat episodes for which datas were obtained, researchers identified a threshold beyond which temperatures and humidities become deadly.
In agreement with human thermal physiology, the threshold was such that as relative humidity increases, lower temperatures become lethal. A web-application accompanying the paper allows counting, for any place on Earth, the number of days in a year when temperature and humidity exceed such a deadly threshold.”
“Climate change has put humanity on a path that will become increasingly dangerous and difficult to reverse if greenhouse gas emissions are not taken much more seriously,” Mora said.
