How Heat Threatens California's Most Vulnerable

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Climate change means it's getting hotter everywhere in California, making it feel like summer for more of the year.

But heat can be a sneaky threat to our health and safety. You might think of it as a party crasher. But heat isn’t leaving. In fact, it’s getting more dangerous and deadly — even in parts of California you wouldn’t expect, like the coast.

From Inland Empire distribution warehouses to genteel homes in San Francisco’s nook-and-cranny neighborhoods, heat creeps in and harms anyone in the way.

For the last three years, KQED Science reporter Molly Peterson has been chasing heat here in California.

She’s found it in homes, schools and workplaces. She’s talked to more than 100 Californians living and working where it gets too hot, to chart some of the ways this unwanted visitor affects the most vulnerable people — laborers, elders and those with high blood pressure and respiratory ailments.

To illuminate how high temperatures affect indoor workers’ ability to function, think and stay healthy, Peterson sent small heat index sensors into places a journalist couldn't go.

People who clean office buildings after the air conditioning shuts off, or attach security tags on fast-fashion apparel draped in plastic hanger bags carried those sensors to their workplaces, where they routinely recorded indoor temperatures in the 90s, even at night.

They also described how hard it is to cool down, take breaks or get other relief on the job.

No federal or state laws regulate heat exposure for people who work indoors.

Heat also lurks where people least expect it, defying the old adage that the coldest winter can be a summer in San Francisco. During Labor Day weekend in 2017, a heat wave killed more than a dozen people in three Bay Area counties.

The average age of the victims was 78, and some succumbed in homes without air conditioning. One woman died inside the place she’d called home all her life, flanked by neighbors she no longer knew.

Like the United Kingdom, where the government includes a cabinet-level Minister for Loneliness, the city of San Francisco recognizes that social isolation can jeopardize health.

That’s why organizers promote block parties and other activities that encourage neighbors to meet one another and band together during emergencies including power outages, earthquakes and extreme heat episodes.

The California Report Magazine devotes its whole show this week to stories about heat, and about ways we can protect ourselves from it.

This documentary was reported and written by Molly Peterson, with grant support from the USC Annenberg Center for Health Journalism Impact Fund. It's part of KQED Science’s partnership with Covering Climate Now, a global collaboration of more than 250 news outlets to strengthen coverage of the climate story.