Palisade and Eaton fires demonstrate increasing danger of rapidly progressing fires

Fences and Eaton Fire, indicating increased danger of rapidly progressing fires

Stephanie Pappas Edited by Andrea Thompson

The Palisades and Eaton fires raced through the Los Angeles area, engulfing thousands of acres in just a few hours and forcing the evacuation of tens of thousands of residents, some of whom were forced to abandon their cars and flee on foot. There were too. At least five people had died in the fire as of Wednesday evening.

Santa Ana’s strong winds fueling fast-moving fires are part of an unfortunate trend. According to a paper published in science October 2024, average peak Daily growth rate of fires in western US more than doubles In California, the average peak growth rate increased by 398 percent. “Fires are starting much faster in California,” said Jennifer Balch, a fire ecologist at the University of Colorado Boulder who led the study.

The study didn’t examine why rapid fires became more common, but Balch said it’s likely due to the same reasons why the western United States has become more fire-prone in general. . “If you warm the climate and essentially dry out the fuels a lot, it makes fires much more likely to spread,” she says.

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This is concerning because these fires are actually the most destructive, Balch said. Although large-scale fires often receive more attention, speed is more important than size when it comes to damage. Balch and colleagues found that 78 percent of structures destroyed by fire in the United States during the first two decades of the 21st century burned in rapidly progressing fires. In fact, a growth rate of more than 4,000 acres per day was one of the best predictors of whether a fire would cause significant damage to homes or other buildings.

“When these fires occur, they can quickly impact communities with little time to prepare or evacuate,” said John, a climate scientist at the University of California, Merced, who was not involved in the study. Abatzoglou says. “And that’s effectively what we’re seeing with some of the fires in Southern California.”

The largest of the fires, the Palisades Fire, has burned more than 15,000 acres since it started on Tuesday, according to the California Department of Forestry and Fire Protection. The Eaton Fire is also looming, burning 10,600 acres since Tuesday. Two additional fires, the Hearst Fire and the Woodley Fire, also broke out on Tuesday and Wednesday, respectively, burning more than 700 acres, the majority of which was blamed on the Hearst Fire.

This rapid destruction is occurring during a dry winter in Southern California after a dry fall, and these conditions occurred on the heels of last year’s particularly wet winter. Abatzoglou said this is the perfect recipe for large, quick fires. Wet years encourage the growth of small, highly flammable shrubs and grasses, while subsequent dry years turn those plants into crunchy matchsticks that can quickly catch fire. “Weather whiplash actually increases the likelihood of very large, fast-moving wildfires,” said Katherine Hayhoe, a climate scientist who studies climate impacts at the Nature Conservancy and Texas Tech University. “I’m working on it,” he says. Rising temperatures caused by greenhouse gas emissions are disrupting wild fire patterns globally, she says, and reducing emissions is key to mitigating their impact.

When fires are started by winds like the Santa Anas, which gusted about 90 miles per hour in Southern California on Tuesday night, embers can be blown far ahead of a fast-moving fire front, sparking new fires faster than they can be extinguished. do. These embers can spell disaster for homes, said Jana Valakovich, county director for the University of California Cooperative Extension for Humboldt and Del Norte counties. “Most of our homes are not robustly built or retrofitted to protect against embers,” she says.

In a warming world, Santa Ana winds are predicted to become less frequent in the fall and spring. According to a 2019 surveyBut its strength is not expected to diminish, and “a single occurrence of Santa Ana winds in a fuel-depleted area is enough for this type of disaster to occur,” Abatzoglou said. . Southern California’s rainy season is compressed, with less fall and spring precipitation. This could extend the fire season and coincide with the typical Santa Ana wind season, which lasts from October to January.

“Winter wildfires should be an oxymoron,” Balch says. But Los Angeles’ experience was similar to another wind-driven event in Colorado, the Marshall Fire, which started on December 30, 2021. A warm, dry winter and strong winds fueled the fire, which burned more than three miles per hour. They set 1,000 buildings on fire and killed two people.

The University of California Agriculture and Natural Resources Fire Network checklist of things to do If you are near an active wildfire and are in an area where evacuation orders have not yet been issued. Barakovich says simple steps like moving flammable materials away from exterior walls, sealing vents and closing pet doors can protect your home from fires. Early steps include replacing standard vent covers with fine mesh that resists embers, removing vegetation within 5 feet of your home’s walls, and removing the last few feet of wood fence lines. This includes being made of non-combustible materials that will not allow direct fire transmission into your home.

Both the Palisades and Marshall fires hit suburban areas that are often thought of as being at low risk for fire. But about 1 million homes in the U.S. have been within wildfire boundaries over the past 20 years, and another 59 million are within about a mile of past wildfire boundaries, Balch said. “That’s a big risk we have,” she added.