If climate change is not remedied with a drastic reduction of greenhouse gas emissions into the atmosphere, lethal heat waves – likely to cause deaths in humans – will become a growing problem and more frequent globally, according to a study published in Nature Climate Change . To the point that in the year 2100 heat waves will affect no less than 74% of the population , when today that percentage is 30%.
Extreme heat waves, such as the one that caused the forest fire that has claimed the lives of more than 60 people in central Portugal or the one that affects the southwestern United States – in Death Valley, California, will reach 53 degrees Celsius – are motivated by climate change that has accelerated human beings on the planet.
According to recent research, led by Camilo Mora, Associate Professor of Geography at the University of Hawaii at Manoa (USA), if greenhouse gas emissions continue to increase at the current rate, in 2100, almost three out of four people could be subjected to at least 20 days of lethal heat a year , when today that figure is 30% (approximately one in three people).
The study, carried out by an international team of researchers, conducted a global analysis of 783 heat waves in 164 countries and 36 countries that took place between 1980 and 2014, with documented deaths, to identify the climatic conditions associated with the greatest risk of death in humans. And they identified a global threshold of mean air temperature and relative humidity that, when exceeded, can be deadly.
Our options: between the bad and the terrible
“Our attitude towards the environment has been so reckless that we are running out of good options for the future, ” explains Camilo Mora. “When it comes to heat waves, our options are now between the bad and the terrible,” he adds.
Why does the expert say this? Because, according to the forecasts they have made, even in a hypothetical scenario in which drastic reductions in greenhouse gas emissions take place, the percentage of the world’s population that is currently exposed to climatic conditions that exceed the fatal threshold during at least 20 days will increase in 2010 to 48% ; but it is that if emissions continue to grow at the rate of today, that percentage of the world population affected will be 74%.
Many people around the world are already paying a high price for heat waves , even with their lives – remember that in 2010 a heat wave that hit Russia caused the direct or indirect deaths of at least 56,000 Russians – and although Mora recalls that forecasting models suggest that the situation will probably continue in the future, “it could be much worse if emissions are not reduced considerably”.
But it does not seem that all the governments of the world are rowing in the same direction: President Donald Trump recently announced the withdrawal of the United States from the Paris Agreement against climate change, signed by 195 nations, considering it “debilitating, disadvantageous and unfair” for your country, which is the second largest global emitter of greenhouse gases.
