More than a fifth of the world’s population would likely experience extreme heat by 2100 if existing measures to slow global warming are kept in place, researchers said on Monday (May 22). According to AFP, the findings was published in the journal Nature Sustainability.
The research states that India (600 million), Nigeria (300 million), Indonesia (100 million), the Philippines, and Pakistan (80 million each) have the largest populations at risk.
Lead author Tim Lenton, head of the Global Systems Institute at the University of Exeter, said that the change “is a profound reshaping of the habitability of the surface of the planet, and could potentially lead to the large-scale reorganisation of where people live.”
The results highlighted the urgent need for action to keep global warming to 1.5C. According to it, doing so would drastically lower the number of people who are at risk. The amount would drop to 500 million. This will represent about 5% of the estimated 9.5 billion people on the planet.
The intensity or duration of heatwaves, droughts, and wildfires have already increased due to just under 1.2C of warming, beyond what would have been possible without the carbon pollution produced by burning fossil fuels and forests. It has been the hottest eight years on record.
“Global warming costs are frequently expressed in monetary terms, but our study emphasizes the astronomical human cost of ignoring the climate emergency,” said Lenton.
The number of people who will be exposed to harmful heat will increase by 140 million for every 0.1C of warming above current levels.
The Threshold for ‘Dangerous Heat’
The threshold for “dangerous heat” has been identified by the latest research. According to the report, the temperature is at MAT of 29C.
Around two MATs, human habitations have historically been most dense. 13C for temperate regions and 27C for more tropical ones.
Everywhere the temperature is rising due to global warming, but in areas that are already close to the red 29C line, there is a clearly larger risk of reaching fatal temperatures.
According to studies, sustained high temperatures at or above this threshold are strongly linked to higher mortality, lower labor productivity, and worse crop yields. Additionally, the likelihood of greater armed conflict and infectious diseases rises as a result.
Only 12 million people globally were exposed to such extremes 40 years ago.
According to the report, that number has climbed fivefold since then and will continue to rise sharply in the next decades.
