Will it happen every year?
That question hangs in the air as Lake County residents suffer through catastrophic wildfire for the fourth time in two years.
This time, the fire is surging even after a relatively wet winter and spring in Northern California. And experts say it’s a reminder that California’s five-year drought has left communities throughout the state vulnerable.
“This is coming to you,” said Kevin Cann, a Mariposa County supervisor who has been speaking for rural communities on a statewide forestry commission. “All of this has its roots in the drought.”
The last two years have been some of the worst for California wildfires, with record heat and historic drought weakening trees and drying the landscape. This year is shaping up to be another rough one.
Through Aug. 13, firefighters had responded to about 3,900 wildfires that burned roughly 113,000 acres, Cal Fire data show. That is about 20 percent more fires and 30 percent more acres burned than the average for the last five years.
Lake County was ripe for wildfires, in part because of all the years it hasn’t burned. A fire threat map produced by Cal Fire a decade ago as part of the National Fire Plan showed the large majority of the county even then at high or very high risk for wildfires.
“The conditions that are on the ground in Lake County are very similar to a tinderbox,” said Democratic state Sen. Mike McGuire, who represents the county. “After five years of drought, the conditions of Lake County are bone dry. There’s a lot of underbrush that has not seen a big fire in decades. That has contributed to the speed and damage of these fires.”
170,000 acres Amount of land scorched by Lake County wildfires in 2015
Last year’s toll included the Rocky, Valley and Jerusalem fires that burned more than 170,000 acres in the county. The majority of the areas burned had not seen significant wildfires in 50 years or more.
The Clayton Fire is burning in areas largely unaffected by major wildfires since at least the 1950s, though portions of its southern perimeter burned in 1983 as part of the Morgan Valley Fire.
Are the areas safer now that they’ve burned? Yes and no. Fire consumes fuels and makes fires less likely in the immediate future. But it is not unheard of. Last summer’s Rocky Fire burned hundreds of acres that also burned during the Morgan Fire in 2000. The Valley Fire burned scores of acres that had been affected by the Twenty Nine Fire in 2012.
This week’s Clayton Fire is burning in a large swath of rugged terrain bordered on three sides by the acreage scorched in last summer’s fires. The blaze has been moving toward land burned in the Rocky Fire, which should help provide containment.
“It would probably put it completely out,” said Scott Stephens, a professor of fire science at UC Berkeley
He and UC Merced fire ecology professor Leroy Westerling were reluctant to connect Lake County’s consecutive damaging wildfire seasons to long-term trends, noting that the county sits in a fire-prone part of the state that occasionally catches ablaze.
“I wouldn’t say it’s any different from other counties in that vicinity. It just seems Lake County has had a lot of ignitions that have impacted people,” Stephens said.
Westerling published a study in May that found Western wildfires have grown longer, more frequent and more damaging since the 1980s. The results suggest that the early spring and late fall weather patterns that have accompanied generally rising temperatures in the West create conditions that worsen wildfires.
This is coming to you. All of this has its roots in the drought.
Kevin Cann, Mariposa County supervisor
The study found the link between a warming climate and wildfire to be strongest at mountain elevations in the Rockies and Sierra Nevada, which experience the greatest swing in seasons. He did not see a strong connection at lower elevations or in scrub landscapes such as Lake County.
But, as climate change contributes to longer, more frequent droughts, the wildfire season will get worse, Westerling said. Higher temperatures increase evaporation, so plants hold onto less moisture in wet years.
“You just get really dry things, so you get a more extreme drought than we’ve seen in recent history,” Westerling said.
Lake County so far has not seen much of the massive tree die-off that Sierra Nevada foothill communities have experienced during the drought years, as bark beetles have taken advantage of short winters to damage weakened conifers.
Cann from Mariposa County said those tall, dead trees are the main reason he and other foothills residents are especially worried about the remainder of this year’s fire season.
“They’re the fear we live with every day,” said Cann, a member of California’s tree mortality task force. “We’re in a precarious position.”
The worst fire to hit Lake County last year took place in September, when the Valley Fire scored 76,000 acres and killed four people. All but four of the state’s 20 most damaging wildfires have fallen later in the fire season, between September and November.
“We’re at the midpoint, but we’re not at the worst point,” said Cal Fire spokeswoman Lynne Tolmachoff.