California wildfires show no signs of slowing down

Tuesday, Santa Anna’s winds swept seaward across Southern California, scattering embers and then fanning the flames of growing wildfires. By nightfall, residents received urgent text alerts warning of possible 100 mph wind gusts, a terrifying escalation that turned an unstable situation into a full-blown crisis. As the winds blew, more embers flew, starting new fires in dry, fragile lands that had not seen heavy rain in more than eight months.

Los Angeles County, which was experiencing drought-like conditions, was a powder keg waiting for a spark. Firefighters faced an uphill battle against winds so strong that planes used to drop water and flame retardants grounded. “All Los Angeles County residents are at risk,” officials warned in a news release Wednesday morning. Evacuation orders have since displaced tens of thousands of residents, and thousands more are awaiting updates. By Wednesday evening, three major fires had scorched more than 13,000 acres as containment efforts delayed: the Palisades Fire in Pacific Palisades and Malibu, the Hearst Fire in Sylmar, and the Eaton Fire near Pasadena, and showed no signs of slowing down, as of press time. It is 0% contained, and has already become the most destructive in California history.

The fires turned catastrophic very quickly due to dry conditions and unusual winds: “Any small spark, whether from a lightning strike, a person, or a campfire, will quickly escalate,” says Jennifer Marlon, a research scientist and lecturer at Yale University. School of the Environment and Yale Program on Climate Change Communication. “Once a fire starts in these conditions, it is very difficult to control,” adds Caitlin Trudeau, senior research associate for climate science at the nonprofit Climate Central News.

Santa Ana wind events are not uncommon. “We see them every year at this time,” says Jason Moreland, chief meteorologist at emergency communications platform AlertMedia. These sloping winds, which originate inland, are caused by a dry high-pressure system coming from the northwest, and a moist low-pressure system from the south. “It’s like you had a hose and you folded it in half to cut off the water. If you cut a hole in the side, you have a lot of pressure to get out,” Trudeau explains. “That’s basically what happens with air.”

However, these winds are much stronger than usual due to a lower jet stream near the Baja Peninsula in northwestern Mexico, Moreland explains. Winds that normally blow to higher altitudes reach areas of lower terrain. “Every few decades, we see wind events of this magnitude,” he says.

While this wind event seems extreme, says Noah Diffenbaugh, a professor and senior fellow at Stanford University Woods Institute for the EnvironmentHe explained that this may only be due to natural weather fluctuations, and more research is needed to find out whether it is caused by climate change.

However, while winds are not unseasonal, climate change is Increases risk Of late or early season wildfires in California. “Not only do we get particularly strong winds, but it’s also a particularly dry season here at the beginning of January,” Diffenbaugh says. Southern California’s rainy season, which runs from October through April, saw record low precipitation, following one of the driest rains on record. As is the rainfall More volatile due to climate changeThe overlap between the monsoon season and the dry season is increasing. “We are seeing a large number of hot, dry and windy days, especially in Southern California,” Trudeau says.