Swelter

A riveting look at what extreme heat does to us—our societies, our neighborhoods, and especially our bodies—as temperatures continue to rise

We’ve all felt it, whether waiting for a bus under the scorching sun or crossing the street in pursuit of a sliver of shade or worrying about our children playing outside on a summer day. The world is getting hotter. In fact, each year, more people die from extreme heat than from all other natural disasters combined.

In Swelter, Bharat Jayram Venkat, the director of UCLA’s Heat Lab, tells the dramatic story of how we’ve come to understand the biology of heat. We meet a Scottish physician who unlocked the mystery of body temperature by studying a crew of shipwrecked sailors, a genteel English traveler in the tropics convinced that the heat was slowly unraveling her mind, and the Harvard researchers who plunged bodies into artificial infernos to test their limits.

But alongside these scientific developments emerged a stubborn set of ideas about bodily difference—who could withstand the heat and why. Colonial physicians insisted that Indian soldiers possessed a natural tolerance that the British could never acquire. Black American workers were assigned to the hottest jobs in steel mills, on the grounds that their bodies were built for it. Venkat shows how this pernicious myth spread across the globe and persists even today, as warehouse workers, incarcerated people, and migrants all live and labor under conditions of relentless heat. What he reveals is a terrible calculus: the comfort and safety of some are made possible by the suffering of others.

Urgent and meticulously researched, Swelter argues that extreme heat is poised to become the defining public health and human rights issue of the twenty-first century. But the future doesn’t have to be bleak. We have the tools not only to survive, but to ensure others’ survival—to build a world that is warmer yet more just. This essential book lights the way.