The number of wildfires in California and the western U.S. this summer may represent a “new normal.”
Nationally, wildfires have burned at least 6.5 million acres in 2015. Federal fire managers say that’s a 38 percent increase over the 10-year average to this point in the year.
UC Berkeley professor Scott Stephens is co-director of the Center for Fire Research and Outreach. He says some of the increase in fire frequency is likely due in part to climate change.
“But there’s no doubt, just the increasing temperatures and less snow on the ground, longer periods for fuels to dry in a Mediterranean climate,” says Stephens. “The physics of that just tell us the fire is going to be able to move more frequently and possibly even higher intensity.”
Stephens says warmer temperatures are causing fires to grow overnight too, and the Rocky and Jerusalem fires are prime examples.
“We’re not having the recovery at night, we’re not seeing as much recovery in terms of temperatures — they’re not going down,” says Stephens. “Humidities are not coming up at night, so we’re seeing more active burning at night, and that happened in both of the recent fires that occurred in Lake County, with burning in the chaparral.”