Slight temperature rise may cause deadly heat waves in India

Washington: India may experience more deadly heat waves in the years to come, with even a slight increase in average temperatures likely to cause hundreds of deaths, a new study warns.

Using data gathered by the India Meteorological Department from 1960 to 2009, researchers from the University of California, Irvin in the US found that when mean summer temperatures in India went from 27 to 27.5° Celsius, the probability of a heat wave killing more than 100 people grew from 13 per cent to 32 per cent — an increase of 146 per cent.

There were only 43 and 34 heat-related fatalities in 1975 and 1976, respectively, when the mean summer temperature was about 27.4° Celsius.

However, at least 1,600 people died from excessive heat in 1998, when the mean summer temperature was higher than 28° Celsius, researchers said.

The average number of heat wave days over the five-decade study period was 7.3 per year. The most heat wave days occurred in 1998 (18), when 1,655 people died, and 2003 (13), when 1,500 people died.

“The impact of global climate change is not a spectre on the horizon. It is real, and it is being felt now all over the planet,” said Amir AghaKouchak, associate professor at UCI.

“It’s particularly alarming that the adverse effects are pummelling the world’s most vulnerable populations,” he added.

“In addition to India, populations in other developing countries in low to mid-latitude regions are specially hard hit by these extreme heat events,” said Omid Mazdiyasni, graduate student at UCI.

“They lack air conditioning that people in richer countries rely on when the heat is unbearable, and they don’t have funds to escape to cooler climates,” he added.

The findings should serve as a wake-up call for governments and international organisations to help improve the resilience of areas most vulnerable to climate change-induced weather events, researchers said.

However, in the wake of US deciding to withdraw from the Paris climate accord, researchers acknowledged the difficulty in building a broad-based coalition to tackle the issue.

“Given the quantifiable impacts of climate change in India and other developing nations in the coming decades, both rich and poor countries should be ramping up our efforts to combat global climate change instead of turning our backs on commitments we have made to the international community,” said Steven J. Davis, associate professor at UCI.