Extreme heat waves are making L.A. firefighters sick, adding new dangers to job

The first pager alert came Wednesday at 3:02 p.m. Brian McGrath of the Ventura County Fire Department said heat-related illness is now a “constant concern.” “It’s hot, it’s dry. “It’s going to result in an increase in vapor pressure deficit — things are going to get drier — and when you have extreme dryness and extreme heat, you’re going to see an increase in fire ignition.” During California’s record-breaking 2020 fire season, about 42% of the state’s population — roughly 16.5 million people — were exposed to a combination of extreme temperatures and high concentrations of fine particulate matter from wildfires at least once, his study found. It ignited around noon Wednesday, and by nightfall it had swelled to more than 5,000 acres in what officials described as a “rapid rate of spread.” Diffenbaugh, of Stanford, said there have been other examples of such fast-growing fires in recent years, “but this is another marker of the conditions that we’re in now — where we’re getting these large areas burned in the 24 hours after ignition.” “The kinds of conditions that make these extreme are the same that make it challenging to fight these fires,” he said. “It’s very hot, and it being very hot elevates the wildfire risk and also makes the physical challenge of responding to fires more acute.” But while wildfires are visible and disruptive, extreme heat is also known as a “silent killer,” and is in fact one of the deadliest consequences of climate change, a Times investigation found last year.