In the valley is where the smoke gets stuck when the wind blows it in from the north and south.
Still, hundreds of thousands of men and women like Ms. Flores continue to pluck, weed, and pack produce for the nation here, as temperatures soar into the triple digits for days at a time and the air turns to a soup of dust and smoke, stirred with pollution from truck tailpipes and chemicals sprayed on the fields, not to mention pollution from the old oil wells that dot parts of the valley.
I drove through the valley last week, from Lodi, just below Sacramento, to Arvin, nearly 300 miles to the south, during a calamitous wave of heat, fire and surging coronavirus infections. I wanted to see it through the eyes of those worst affected: agricultural workers. Most of them are immigrants from Mexico. Mostly, they earn minimum wage ($13 an hour in California). Mostly, they lack health insurance and they live amid chronic pollution, making them susceptible to a host of respiratory ailments.
Climate change exacerbates these horrors.
By noon one day last week, temperatures had soared to 100 degrees Fahrenheit in Lodi, in the valley’s northern stretch. Still, Leonor Hernández, 38, mother of three, was at work. Dressed as usual in an oversized full-sleeved shirt and hat, bandanna covering all but her eyes, water bottle stuffed into her pocket, she walked up and down the cherry orchard, scooping up stray branches hacked off after the harvest, hoisting them into a bin. The ground had to be cleared for the next spraying of pesticides, smoke or no smoke.
As the week progressed and more acres burned, the air grew increasingly toxic. Her head and chest hurt. She was coughing. The San Joaquin Valley Air Pollution Control District urged residents to stay indoors.
Good advice, in theory, Ms. Hernández said. “But we need to work, and if we stay indoors we don’t get paid,” she said. “We have bills for food and rent to pay.”
California is one of two states, along with Washington, with heat standards for outdoor workers. Employers must provide shade, usually a bench with a canopy, and drinking water. Many labor contractors stop work when it gets too hot, but the law doesn’t require a halt at any given temperature threshold.