Cities Are Bearing the Brunt of Heat’s Crippling Effects

With record-breaking heat waves rippling around the globe, city governments struggle to keep people safe in a warming world.

An Indian boy tries to cool down in Mumbai on May 29. More than 1,400 people died in a major heat wave that swept across India as temperatures neared 50 degrees Celsius. (Photo: Imtiyaz Shaikh/Anadolu Agency/Getty Images)

Jun 23, 2015· 2 MIN READ
Katharine Gammon has written for Nature, Wired, Discover, and Popular Science. A new mom, she lives in Santa Monica.

This week, a devastating heat wave killed more than 700 people in Pakistan. Last month, it was heat that killed 2,320 people in India—and for most of the globe, the hot summer months are just starting. That’s got cities around the world putting together action plans for what to do when the mercury starts to skyrocket.

It’s likely to get worse: A report released by the EPA on Monday predicted that if we continue polluting as we are now, heat waves in 49 major U.S. cities are expected to kill 12,000 people per year by 2100. Hold on—there’s more: A majority of the world’s population is living in urban areas, leaving more people exposed to the city-instigated “heat island” effect and the dangers that come with it.

So, Why Should You Care? Heat is seen as an inconvenience, but it’s really a public health issue, said Kim Knowlton, a senior scientist at the Natural Resources Defense Council. In the U.S., cities are starting to prepare for heat waves, and that means beginning with the elderly.

“Our vulnerability to heat is increasing as people in the U.S. are getting older,” said Knowlton. “Many millions of baby boomers—age 65 and older—are more vulnerable to heat.”

That’s because as we get older, our heart and lung systems—regulators of core temperature—get weaker, making us more susceptible to heat’s effects. In addition, people with asthma and respiratory issues are more prone to getting ill from too much heat.

One thing that could help is better prediction of upcoming heat waves. Right now, the weather service can predict heat about a week or so in the future, and health departments usually work out a heat wave plan about three days in advance.

Those plans include sending text messages to residents reminding them to watch the weather reports, use shade, drink water, and check in on elderly folks who have a hard time getting out of the house.

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“Those are low-tech, but they’re incredibly powerful methods,” said Knowlton. “We encourage people to take heat incredibly seriously because climate change is making heat waves more intense and longer-lasting.”

Plans have to be fine-tuned to local conditions and local realities. Health issues can crop up in Minnesota at lower temperatures than in Florida because people’s bodies aren’t used to the heat—and their buildings and local governments aren’t prepared either. Only about 40 percent of U.S. counties have existing heat preparedness plans, but Knowlton expects that number to rise in the coming years.

In India, where the heat and humidity are generally much higher, the city of Ahmedabad was the first in the country to create a heat action plan. The plan worked to make people aware of heat’s dangers, create an early-warning system, and boost health care workers’ ability to recognize and treat heat-related illness.

“In the long term, as we see extreme heat wave events become more frequent and severe, the systems in place here in the U.S. can potentially benefit from public health lessons learned in warmer parts of the world, such as India,” said Amrutasri Nori-Sarma, a doctoral student at the Yale School of Forestry and Environmental Studies and a coauthor of a paper about Ahmedabad’s plan.