India along with Pakistan and Bangladesh could witness deadly heat waves by the end of this century, with heat and humidity levels that may likely exceed human tolerance, a research has claimed.
The findings showed that these heat waves could begin within as little as a few decades and will also include the fertile Indus and Ganges river basins that produce much of the region's food supply.
The summer of 2015 also produced one of the deadliest heat waves in South Asia, killing an estimated 3,500 people in Pakistan and India.
And yet, India and China remain two countries where emission rates of greenhouse gases continue to rise, driven mostly by economic growth, said Elfatih Eltahir, a professor at the Massachusetts Institute of Technology (MIT).
"So I think these results pose a dilemma for countries like India. Global warming is not just a global problem — for them, they will have some of the hottest spots on the planet," he said in the paper in the journal Science Advances.
Further, the research revealed that by the end of 21st century, lack of serious reductions in global emissions would lead to a rise from about 31 degrees Celsius to 34.2 in wet-bulb temperatures — a combination of high temperature and high humidity.
At a wet-bulb temperature of 35 degrees Celsius, the human body cannot cool itself enough to survive more than a few hours.
"It brings us close to the threshold" of survivability as "anything in the 30s is very severe", Eltahir said.
Currently, nearly 2 per cent of the Indian population sometimes gets exposed to the extremes of 32 degree wet-bulb temperatures.
And because the region is important agriculturally, it is not just those directly affected by the heat who will suffer.
"With the disruption to the agricultural production, it doesn't need to be the heat wave itself that kills people. Production will go down, so potentially everyone will suffer," Eltahir noted.
While the study provides a grim warning about what could happen, it is far from inevitable, Eltahir stressed.
"With mitigation, we hope we will be able to avoid these severe projections. This is not something that is unavoidable," he said.