As fire officials warn of the seasonal Santa Ana winds that stoke fires throughout the region, a study released last week shows western wildfires are larger and more frequent than they used to be.
Researchers at Climate Central, a Princeton, N.J.-based non-profit group that studies climate change, found a seven-fold increase in fires of 10,000 acres or more and a five-fold increase in fires of 25,000 acres or more since the 1970s.
"I think that the magnitude of the increase in large fires was surprising," said Richard Wiles, director of research for Climate Central.
Fire officials in California weren't shocked by the findings.
Cal Fire reports that 12 of the state's 20 largest wildfires since 1932 have occurred in the last decade.
"A lot of us in my generation, our mentors and our captains and battalion chiefs, they would talk about once-a-career fires, or `The Big One,"' Cal Fire spokeswoman Janet Upton said. "My generation is having once-a-career fires (regularly). This season, several years of experience have been crammed into two months."
Nationally, with nearly two months left before the official fire season is over, fires have burned more than 8.6million acres, or 30percent more than in an average year, according to Climate Central's report, titled "The Age of Western Wildfires", which was released Sept. 18.
The report looked at 42 years of data from the U.S. Forest Service.
Researchers said the annual number of wildfires greater than 1,000 acres on Forest Service land has been on the rise, with twice as many fires of more than 1,000 acres each year, and an average of more than 100 per year between 2002 and 2011, compared with fewer than 50 during the 1970s.
Since that time, the average number of fires of more than 1,000 acres each year has nearly quadrupled in Arizona and Idaho, and doubled in California, Colorado, Montana, New Mexico, Nevada, Oregon, Utah and Wyoming, according to the report.
The analysis showed that on average, wildfires burn twice as much land each year as they did 40 years ago, and in the past decade, the average annual burn area on Forest Service land in the West has exceeded 2million acres. That's more acreage than found in all of Yellowstone National Park.The definition of a wildfire season in the West is changing.
Warmer temperatures and a decrease in the snowpack has increased wildfire risks in most of the region, researchers said.
"The fire season is about two and a half months longer than it was in the 1970s," Wiles said. "Those impacts are clearly related to climate."
Indeed, researchers found that across the West, the first wildfires of the year are starting earlier, and the last fires of the year are starting later, making fire seasons 75 days longer now than they were 40 years ago.
But some say the increased fires should not be blamed on the climate.
Among them is Bill Patzert, a climatologist with the Jet Propulsion Laboratory in Pasadena. Patzert said global warming is real, and he regularly speaks on the issue, but the rash of wildfires that are burning in the West are not the direct result of climate change.
"The simple formula I use is: People equal fire," Patzert said.
Patzert said millions of people have moved into fire zones such as the Santa Ana wind corridors, and urban and suburban sprawl is increasingly creeping into wild areas, which leads to a higher potential for major fires to ignite either by accident or by arsonists.
Add a rather lax attitude by many to clear their properties of brush and debris, and there should be no surprise that large fires are on the increase, he said.
"Ninety percent of the fires are human-ignited," Patzert said.Patzert said part of the problem lies with local governments that don't enforce fire zones and have cut back on public safety.
The other issue is that the Forest Service continues to fight too many small fires, Patzert said. When small fires are allowed to burn, they kill the fuels necessary for larger fires to rage out of control, he said.
The situation presents a Catch-22 in and around places like the San Bernardino National Forest, where residents expect firefighters to routinely put out small blazes.
"In this highly urbanized forest, you can't let fire take its natural course as it did in pre-settlement days, as it did 100 years ago," said Forest Service spokesman John Miller. "Now that we have lots of people living in and near the forest, that's no longer an option."
In that regard, Cal Fire says fire safety needs to be on the minds of all Southern California residents, but especially those who live and play in the mountains and wildland areas.
Battalion Chief Preston Fouts of Cal Fire's San Bernardino Unit/Fire Prevention said in a news release that "residents in the urban intermix and wildland areas need to maintain a fire safe clearance of a minimum of 100 feet around all structures or to the property line."
The defensible space gives firefighters the area they need to defend homes from fire, according to CalFire.Miller said mountain residents in recent times have indeed been better at clearing their properties of debris and brush.
"I think in the mountain communities and foothill communities the public awareness is much higher than it was 10 years ago," he said.
Still, fire officials such as Upton say California is more frequently experiencing prolonged fire seasons, and residents cannot be vigilant enough.
"In some areas of the state, including (Southern California), we've seen year-round fire seasons," Upton said.
And she warned that it could get worse this year, saying that October, in addition to late August and September, is a month where the state typically sees the largest, most damaging fires.
According to the Boise, Idaho-based National Interagency Fire Center, the country's wildland firefighting support network, this year's fire season has seen "a heavier and more continuous than normal fuel bed" (of brush and trees) that is creating conditions for fires to spread more rapidly and into areas not normally seen this time of year in the West.
The agency predicts an above-normal significant fire potential to continue over portions of Southern California into October, with a return to normal after October or early November."The majority of these (current) fires are fuel-driven, in the absence of significant winds," Upton said. "They're driven by fuel conditions and topography. That's disconcerting."
In other words, Southern California hasn't fully experienced the full impact of Santa Ana winds during this fire season. It's the final ingredient that could cause disaster.
Cal Fire warns of the "Devil Winds" that whip through Southern California from October through December. Some of the region's most devastating fires, including the 2003 Old and Grand Prix fires, were driven by strong, dry Santa Ana winds.
The Santa Ana wind cycle forms when high pressure from the northeast pushes hot dry winds into Southern California. These winds initially cycle through about every ten days, and can increase to about every three or four days leading in to December.
"The big question is to what level of intensity, with what frequency and how will the events align with the ignitions," Upton said.
Another consideration is the funding and manpower needed to keep up with the seemingly endless string of wildfires.
Authorities last month started charging residents of rural, fire-prone areas more for firefighting, with the first bills of about $115 per property going out to roughly 800,000 Californians.
The fee will bring in an annual $84 million slice of the $1.1 billion Cal Fire budget.
Upton said the state's money woes have yet to cut into Cal Fire's ability to fight blazes up and down the state.
Its preventive services units in both Northern and Southern California have done a good job of assessing fire threats, she said. "I can tell you that the budget cuts over the last couple of years did not affect our ability to staff ahead of fire conditions," Upton said.
In the meantime, climatologists continue to disagree over the direct cause of wildfires.
Wiles said unless something is done about climate change, the West will continue to see a surge in wildfires because it's not just a matter of managing forests better.
"I think there's a lot of forest out there," he said. "It's just really hard to manage your way out of those kinds of effects."Patzert said it's about the population density.
"The biggest killer is, what the hell are all those people doing, living in the wildfire area?" he said.
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