South Asia braces for deadly heatwaves

Deadly heatwaves in South Asia are likely to become more common in the future, with the region's exposure to lethal heat stress potentially nearly tripling if global warming isn't curbed, researchers said.

But the threat could be halved if the world meets a goal set under the Paris Agreement on climate change to limit warming to 1.5 degrees Celsius above pre-industrial times, researchers said in a study published this week by the American Geophysical Union.

"The future looks bad for South Asia, but the worst can be avoided by containing warming to as low as possible," Moetasim Ashfaq, a climate scientist at the US-based Oak Ridge National Laboratory, said in a statement.

The new study used climate simulations and projected population growth to estimate the number of people who could experience dangerous levels of heat stress at warming levels of 1.5C and 2C.

It looked at the predicted "wet bulb temperature". Health experts and scientists say that at a wet bulb temperature of 32C labour becomes unsafe and at 35C the body can no longer cool itself.

If warming hits 2C, the number of South Asians exposed to unsafe temperatures could rise two-fold, and nearly three times as many people could face lethal heat, the study said.