【AI前沿】California’s Wildfire Season Is Already Overactive

Brian KahnScienceMay 19, 2026 6:20 PMCalifornia’s Wildfire Season Is Already OveractiveMajor fires are threatening homes and ecologically sensitive areas following a hot, dry winter.The Sandy Fire burns on Monday, May 18, in Simi Valley, California.Photograph: AP Photo/Ethan SwopeCommentLoaderSave StorySave this storyCommentLoaderSave StorySave this storyIt’s May, butCalifornia is already getting a taste of what peak fire season could look like, as out-of-control blazes pose a danger to infrastructure and some of the most threatened trees on the planet.A combination of high winds and heat has contributed to a trio of major fires in Southern California.The largest among them is the Santa Rosa Island Fire, which started over the weekend in Channel Islands National Park after a stranded sailor used flares to signal for help. The blaze has consumed roughly 16,600 acres—almost a third of the entire island. While some structures have been lost, the biggest is a grove of Torrey pines, which are among the rarest trees in the world.Torrey pines are considered critically endangered by the International Union for Conservation of Nature. Thegroup has warnedthat the grove on the island faces “high potential risk from destructive fires.” While the Santa Rosa Island Fire burned through the grove, there’s hope that the worst-case scenario may not have come to pass.“Upon initial assessments, fire crews are observing that the fire intensity was low and that the stand remains intact,” Mike Theune, the fire information officer assigned by the federal government, writes in an email. “When safe to do so, a fire effects crew will be assigned to make a full determination of condition and any long-term effects.”While smaller, the Sandy Fire has forced thousands to evacuate in and around Simi Valley, located about 35 miles northwest of downtown Los Angeles. Fire activity increased on Tuesday morning as high winds whipped the flames across nearly 1,400 acres.The fire is only 5 percent contained, while the Santa Rosa Island Fire isn’t contained at all. Because homes and businesses are threatened, the Sandy Fire has received more aerial resources to quell the flames. The River Fire has also burned 3,535 acres in Kern County and is 15 percent contained.In the early stages of fire season, nearly 41,000 acres have burned across the state, according to the California Department of Forestry and Fire Protection. But that’s well above the five-year average of 23,380 acres burned by this date and could be a harbinger of what’s to come in the state and across the West.Record-breaking heatobliterated already-meager snowpackthis spring, leaving states primed to burn. The most recent snowpack measurements show California’s Sierra Nevada range harbors just 9 percent of its usual snowpack for this time of year, while many basins in other parts of the West have no measurable snow at all, according to federal data.Hot weather is, of course, a hallmark of climate change. Arecent analysisby the nonprofit Climate Central found that April 1 snowpack—a key date for measuring what’s on the ground—has declined across the West by 18 percent since 1955.All of which is to say that while the early season fires are bad, the West hasn’t seen anything yet.