Mega-storms like Harvey and Maria capture the headlines. But the real killer weather comes from another quarter: Deadly heat waves.
According to the U.S. National Weather Service, heat-related causes killed more people over the past 30 years than other weather phenomenon. And those numbers might be low — death by heat is likely underestimated because “many deaths during heat waves are attributed to other causes,” says Gulrez Shah Azhar, an assistant policy researcher for the RAND Corp.
Heat-related deaths are expected to rise as more people move to heat-trapping cities; two-thirds of humanity is expected to live in urban areas by 2050.
The poor, elderly and infirm are the most likely to die from extreme heat, especially in the U.S.; during Chicago’s three-day heatwave in 1995, many of the 730 who died were older people living alone. Elsewhere, women die from extreme heat far more often than men.
A new report by the Thomson Reuters Foundation says that in India, preparing household meals means a choice for women between cooking inside, turning one-room homes into ovens, or cooking outside, where they risk heat stroke.
Women there can also be at greater risk of dehydration; many avoid drinking ample amounts of water to limit trips to outdoor toilets, where they risk harassment or even rape and murder.
Climate change is expected to make the problem worse. A recent study of temperatures in India between 1960 and 2009 found that a rise of less than one degree Fahrenheit significantly increased the number of heat waves and the probability of heat-related deaths.
A heat wave in 2015, when temperatures reached 118 degrees Fahrenheit, left more than 2,330 Indians dead.
How to respond? Getting people to stay indoors and hydrated during heatwaves is critical, says Azhar. Humid Bhubaneswar, in eastern India, has since last summer doubled the number of roadside water kiosks.
Ahmedabad, a city of 5.5 million, initiated a weather forecast-based early warning system of impending heat waves and worked to ensure that there were ample supplies of ice packs, water coolers, and medicines to bring relief from the heat.