As firefighters battle multiple wildland fires across the western U.S., government officials are warning that California could be facing one of the costliest and most damaging wildland fire seasons on record. Five years of severe drought conditions and ongoing bark beetle infestation have left an estimated 40 million dead and dried-out trees in California, 29 million of which died last year alone. Despite lower than expected rainfalls last year, El-Nino precipitation was enough to spur the growth of weeds, grass and brush. With temperatures now spiking into triple digits, that brush is dying and drying out, creating a flame propellant that allows wildfires to spread faster and burn hotter.
Dense vegetation and heavy timber surrounding many of the recent fires have forced firefighters to initially depend on low-flying air tankers and helicopters carrying fire retardant and smoke jumpers. Those firefighting aircraft been repeatedly grounded by recreational aerial drones spotted flying in the area against FAA flight restrictions. Although not a new challenge, such delays can significantly hamper the containment of these rapidly spreading fires.
California experienced two of its worst wildland fires in history in 2015. The Valley Fire burned 1,958 structures totaling at least $1.5 billion in economic loss. The Butte Fire burned 818 structures totaling at least $450 million in economic loss. At least 40 wildland fires larger than 200,000 acres – so-called “megafires” – burned over the past ten years in the U.S. compared with 21 in the decade earlier, according to the National Interagency Fire Center. About 70 million total acres burned in the U.S. over the past decade, compared with 55 million in the prior decade; 30 million acres burned from 1986 to 1995, according to the center.
Federal officials say wildfire danger nationwide has increased with climate change. Fire seasons have lengthened by an average of 78 days since 1970, and the average number of acres burned annually has doubled since 1980. Last year, a record 10.1 million acres burned nationwide and 4,500 homes were damaged or destroyed. The National Interagency Fire Coordinating Center said that Hawaii, Alaska, California and other parts of the Southwest face an above-average threat this season.