Transcript:

As the climate warms, heat waves are growing more intense. And more places are at risk of reaching temperatures that people cannot tolerate – even if they’re drinking lots of water or resting in the shade.

Matthews: “Doing things like moderating physical activity. Staying out the sun, being well hydrated – the traditional … advice that’s given during extreme heat episodes, that won’t cut it.”

Tom Matthews is a climate scientist at King’s College London. He says at a certain point, people’s body temperatures start to rise uncontrollably, and they cannot cool off without external cooling like air conditioning.

In a recent study, his team estimated that if the world warms about 1.8 degrees Fahrenheit more, a total area roughly the size of the U.S. could reach temperatures that cross this dangerous threshold – even for young, healthy adults.

An even larger area will reach temperatures that could be deadly for older adults, whose threshold is lower.

Matthews: “It’s generally subtropical and tropical locations. South Asia stands out as particularly at risk. Saharan Africa, too, very much at risk.”

So increasing people’s access to air conditioning in these and other at-risk areas will be critical for saving lives.

Reporting credit: Sarah Kennedy / ChavoBart Digital Media