LOS ANGELES — Embers drifting from a campfire in a seaside canyon ignite a wildfire that incinerates 53 homes in Malibu.
A man driving on a national forest road stops on tinder-dry grass. The hot engine acts like a match, kindling a wildfire that burns thousands of acres.
And authorities suspect that a blaze that destroyed 78 homes in the Santa Barbara area last week was started by sparks from a power tool being used to clear brush.
A growing number of wildfires in California are joined by a common, incriminating back-story: People caused them.
Government statistics show that people were faulted for 5,208 wildfires in Southern California in 2008, the highest number since at least 2001. Between 2006 and 2008, Southern California was the only region of the country to see a significant jump in the number of wildfires blamed on people, an unsettling statistic given the damage that can follow.
There is no single cause for the increase, experts say, with issues ranging from better investigations and reporting to the warming effects of climate change. But most agree: In a densely populated, drought-stricken region where development pushes into areas known to burn, the result is predictable.
"As the drought continues in California, there are going to be more human-caused fires," says Don Smurthwaite, a spokesman for the National Interagency Fire Center in Idaho.
"You can see the spread of development in virtually every area of the West," he says. "More people is always going to equate to more fires."
Southern California's fire season was once thought to be limited to the fall, when Santa Ana winds roar through mountain passes into heavily populated coastal areas. But it's now seen as a year-round danger, a conclusion witnessed in Santa Barbara last week. Warmer, drier weather in a region of more than 20 million people with a history of wildfires is proving a combustible mix, fire center figures suggest.
And some of those blazes are leading to the courtroom, where prosecutors are bringing charges from arson to negligence.
Gov. Arnold Schwarzenegger declared a statewide drought in June and in February declared a state of emergency because of three years of below-average rain and snowfall in California.
In Los Angeles, rainfall for the year that began July 1 is nearly 6 inches below average in a city that typically sees scant precipitation. In the state's agricultural Central Valley, three years of drought have forced farmers to let thousands of acres of cropland turn to dust.
Nationally, about 70,000 wildfires in 2008 were attributed to human causes — a thoughtlessly flicked cigarette, a campfire left smoldering, a fallen power line. That's about the same number as 2001, although the figures fluctuate from year to year. Since 2001, the peak was 80,220 wildfires caused by humans in 2006, according to fire center records.
In Southern California, the number of wildfires caused by people was about flat — roughly 4,000 — between 2001 and 2005. It dipped to 3,200 in 2006. Then, those figures increased sharply, to 5,140 in 2007 and 5,208 in 2008, according to the data.
The increase in Southern California stands out. In Alaska, for example, the number of wildfires blamed on people has been gradually slipping since 2004. Nationally, the number of wildfires attributed to human causes dropped in 2007 and 2008.
Lightning strikes account for just a fraction of all wildfires — about 8,800 across the nation in 2008. In Southern California, the number of wildfires blamed on lightning dropped from 409 in 2006 to 291 in 2007 and 174 last year.
Firefighters this week were extinguishing the last of a now-smoldering wildfire in the Santa Barbara area, which at its peak forced thousands of people to flee their homes. It blackened about 13 square miles. Authorities are trying to identify the person using a power tool that they believe caused the blaze.
Given the large number of wildfires in the state, only a small number lead to criminal or civil cases. The U.S. Forest Service alone recorded nearly 400 arson wildfires since 2005, records show. Prosecutors have wide discretion, and recent wildfires in Southern California have produced a patchwork of results in the courtroom.
A pipe grinder who accidentally started a 240,000-acre wildfire in Santa Barbara County in 2007 that injured 40 people initially faced felony counts, but those charges were dismissed. He did not have to pay restitution to injured firefighters, pleaded no contest to a misdemeanor of negligently setting a fire and was fined $200.
Earlier this week, a man was sentenced to 16 years in prison after pleading no contest to arson for setting a series of fires in Los Angeles' sprawling Griffith Park last year.
Ten people who built a campfire were not charged with igniting a wildfire last fall that burned more than 200 homes in Santa Barbara and neighboring Montecito because investigators could not prove who caused the wildfire.
They were charged with misdemeanor trespassing and unlawfully building a campfire. The wildfire seriously injured two people and destroyed rows of multimillion-dollar homes, including actor Christopher Lloyd's $11 million home in Montecito.
"Two things are important for prosecutors to look at: one is the intent ... but on the other hand, there is the harm," says Riverside County Deputy District Attorney Michael Hestrin.
"It's a judgment call," he says. "No two cases are the same."
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