With reservoirs full and snow still deep across the Sierra Nevada following one of the wettest winters in recent decades, California is off to a slow start this year to fire season.
But Gov. Gavin Newsom and state fire leaders urged residents on Thursday not to be complacent as July Fourth nears and summer weather begins to heat up.
“In the last four years we’ve had two of the most extreme wildfire seasons — some of the worst and most destructive in terms of acreage and property and lives lost — and then two of the more modest fire seasons,” Newsom said during a visit to the Cal Fire Air Attack Base in Grass Valley, California.
“We live in this new reality,” he added, “where we can’t necessarily attach ourselves to some of the more predictive models of the past because of a world that is getting a lot hotter, a lot drier and a lot more uncertain because of climate change.”
On Thursday, 487 wildfires burned across Canada, which have choked East Coast cities and parts of Europe in thick smoke. The Canadian Interagency Forest Fire Centre said the 2023 wildfire season, which has seen 19 million acres burn so far in Canada, already is the worst in that country’s recorded history, exceeding 1989.
But in California, where atmospheric river storms this winter ended a three-year drought, caused flooding and buried the Sierra Nevada in the deepest snowpack in 40 years, wet conditions helped keep wildfires at bay.
As of Monday, only 7,601 acres had burned statewide on lands overseen by Cal Fire and the U.S. Forest Service. That’s less than half of the 17,326 acres that had burned this time last year, and only a quarter of the five-year average of 28,875 acres, according to Cal Fire statistics.
It’s not just that fewer acres have burned. Fewer fires have started.
Through Monday, 2,251 wildfires started in California this year, compared with 3,284 this time last year, and 3,067 on average over the past five years, according to Cal Fire.
Traditionally as summer begins, fire officials warn that every year could be a bad fire year. It’s as much of a prediction as a public relations message to remind resident to remain vigilant.
But in recent decades, California’s worst fire years, measured by total acres burned, have happened more often after dry winters than after wet winters. Even though grasses grow high during wet winters, providing fuel for fires to burn in the summer, moisture levels remain higher in shrubs and trees for longer after wet winters, fire researchers say.
Currently moisture levels in brush are about a month behind where they normally would be, said Craig Clements, director of the Fire Weather Research Lab at San Jose State University.
In other words, plants have as much moisture in them now as they historically would have in May, which is reducing risk.
“The higher the fuel moisture, the lower the potential for ignition,” Clements said.
As hotter weather arrives, fire risk will increase, he said, particularly in September and October, which are usually the most dangerous for wildfires because conditions are driest, and seasonal winds often blow from inland toward the coast.
“Everything dries out in the fall,” Clements said. “That’s when we should expect the biggest potential for large fires.”
Clements said the mild fire season so far is also due to the fact that California has had cooler-than-normal weather in the past few months. And the fact that snow doesn’t burn.
“Some of our biggest fires occur in the Sierra Nevada,” he said. “There’s still a big snowpack there this year going into July.”
California has suffered from from repeated brutal fire years over the past decade. That’s in part because of two droughts, hotter summer temperatures, years of overgrown forests that state and federal officials are now racing to thin, and the failure of powerlines owned by PG&E and other utilities in dry, windy conditions. The five largest wildfires in the state’s recorded history all occurred since 2018.
The deadliest, the Camp Fire, killed 85 people in November 2018, burning 18,000 homes and other structures in the town of Paradise, and other surrounding communities in Butte County.
In 2020, heavy smoke from multiple fires choked the Bay Area with the worst air pollution in the world for several days, turning skies orange. That year 4.3 million acres burned. The following year was another bad one, with 2.6 million acres burning, including the Caldor Fire, which forced the evacuation of 20,000 people in South Lake Tahoe.
But last year was relatively mild. Despite record heat waves that sent temperatures soaring to 115 degrees in the Bay Area and Southern California, 363,939 acres burned statewide last year, a drop of about 85% from the year before. Early fall storms in September twet much of the north and south, and persistent fog helped keep fire danger lower-than-normal.
On Thursday, Cal Fire Director Joe Tyler noted that the winter of 2016-17 was wet. But the summer of 2017 saw a sizeable fire season, with 1.5 million acres burned, including in major blazes in Napa and Sonoma counties, and the Thomas Fire in Santa Barbara County.
“I’m asking each of you to be mindful of how quickly a fire can have devastating consequences,” Tyler said.
He and Newsom highlighted several major firefighting changes in the past five years. Among them, the state purchasing Sikorsky Blackhawk helicopters, which can carry 1,000 gallons of water, nearly three times as much as the aging 1970s-era Huey helicopters they are replacing.
The Sikorsky helicopters also can fight fires at night, unlike the older models. The state has helped create a network of more than 1,000 hilltop automated video cameras to detect fires early; has built 3D models of 30 million acres; and has put in place a high-tech system to better track and model fires from aircraft called FIRIS.
“Cal Fire is prepared,” Tyler said. “Cal Fire is fully staffed with all of its fire engines, its bulldozers, its aircraft and all of the available hand crews we have that can respond to fires.”
