Tree removal projects — and burn scars from previous wildfires — can often slow or stop the spread of new fires. That simple calculus of creating a less-combustible landscape should equate to fewer and smaller fires, even with the dozens of variables that go into sparking wildfires.
California has a goal, in conjunction with the federal government — which owns the majority of the state’s forested land — to “treat” a million acres annually by 2025 (PDF). That entails setting and monitoring low-intensity small fires, building and extending fuel breaks and clearing rights-of-way.
But it’s painstaking and slow: In the 2021–22 fiscal year, the state conducted nearly 600 fuels-reduction projects across 101,000 acres. An additional 21,000 acres have been cleared since July.
76,788
The state’s largest wildfire of the year, the Mosquito Fire, which burned 76,788 acres in national forests, turned out to be puny by recent standards, especially when compared to 2020’s million-acre fires and last year’s 963,000-acre Dixie Fire.
Size isn’t everything. Although not huge, the Mosquito Fire, which ignited in early September, was stubborn in the extreme, abetted by its location in steep canyons where fighting the flames was difficult. The fire quadrupled in size in one day, and it took almost three months for firefighters to control it.
The scenario of that fire burning in a dense and dry landscape was sobering enough to prompt evacuations and weeks of defensive actions including closing parts of Tahoe and El Dorado national forests at peak camping season.
A sustained deluge of rain in October was credited with finally helping to suppress the blaze.
3
Along with the Mosquito Fire, two other wildfires were also, in part, extinguished by an increasing rarity in California: rain.
Firefighters in the Rockies have an axiom: Snow puts out fires. California’s analogue occurred this summer when unexpected rainstorms doused two particularly nasty fires: the Fairview Fire in Riverside County and the deadly McKinney Fire in Siskiyou County.
Moisture from Tropical Storm Kay bailed out the Fairview Fire in September, and thunderstorms doused some flames with three inches of rain on the McKinney Fire in August. But the storm also sparked lightning, which set off mud and debris flows.
It’s not just precipitation that influences the severity of the fire season. It’s also wind.
As wildfires in the northern part of the state were tamped down at the end of summer, attention turned to the south, where fires often are triggered by dry Santa Ana winds. Perhaps to remind everyone who’s in charge, winds gusted through Southern California over the Thanksgiving weekend, setting off red flag alerts for brush fires. But no large fires erupted.
12th
If history is any guide, the 12th month of the year can’t be counted on to be quiet.
In 2017 Southern California exploded under strong Santa Ana conditions, sparking 29 wildfires, including the Thomas Fire, which burned 281,893 acres in Santa Barbara and Ventura counties, making it at the time the largest fire in California history.
The month-long barrage started in December, ran across 440 square miles and destroyed more than 1,000 structures. It burned into January.
In 2020 more than a half-dozen wildfires started in December, a month that is reliably cool and moist — or sometimes hot and dry.