Editorial: The climate-change fire alarm from Northern California

Big deadly fires are nothing new to California, particularly during fire season when the Santa Ana or Diablo winds blow hot and dry, making tinder out of trees and bushes that have been baking all summer long.

But the firestorm now raging through Northern California isn’t the typical wildfire. For one thing, it’s not just one fire but close to two dozen. For another, these fires are not only threatening hard-to-reach rural or mountains area, but they also have torn through suburban neighborhoods. More than 3,500 homes, commercial buildings and other structures have been reduced to ash. The Tubbs fire jumped across the 101 Freeway in Santa Rosa, for heaven’s sake.

The flames moved so fast that they caught people unaware and unprepared to flee. As of Wednesday, when the wind picked up and shifted the flames toward more populated communities, the death toll stood at 21 people, with more than 500 still missing. By Thursday morning, fire officials believe, some of the individual fires may meet and merge into one mega-fire.

At this point the fires rank collectively as the deadliest blaze in California since the Oakland Hills fire in 1991, which claimed 25 lives. The fires are also unusually destructive; they have burned more structures than the Oakland Hills fire, the Cedar fire that raged through rural communities in San Diego County in 2003, or the Station fire that burned through the Angeles National Forest in 2009. When this is over, it may well be the state’s worst fire catastrophe in recorded history by any measure.

This is not just bad luck. Coming on the heels of other large-scale natural disasters — Houston inundated by a slow-moving tropical storm, swaths of Florida and the Caribbean ripped to shreds by a monster hurricane, much of Puerto Rico leveled by an equally powerful hurricane, a handful of Western states swept by massive fires that burned up millions of acres — one can’t help but see a disturbing pattern emerge. Those superstorms that scientists warned would result from climate change? They are here. The day of reckoning isn’t in the future. It is now.

We don’t yet know what started the fires in Northern California, but we have a good idea of what made them so destructive. Authorities blame a combination of factors: winds so strong they knocked down power lines, extremely dry conditions, and an abundant supply of combustible material from a years-long drought that killed millions of the state’s trees or left them vulnerable to insect infestations. Ironically, this year’s unusually rainy winter probably contributed to the problem by producing burnable new growth.

All of those factors are exacerbated by the warming world. Hotter summers yield more fuel for fires and stronger winds to fan the flames. And this summer was California’s hottest on record, a milestone dramatically illustrated when San Francisco hit 106 degrees on Sept. 1 during a statewide heat wave.

Similarly, scientists say climate change doesn’t cause hurricanes, but it can make them bigger and more destructive. Higher air temperatures mean more evaporation and heavier rains outside of drought zones, and warmer seas intensify the size and fury of the storms themselves. It’s a double whammy that has contributed to an unusually severe hurricane season this year.

Burning fossil fuels is not the only human activity that contributes to the destruction wrought by wildfires and hurricanes. So does the relentless march of humans to develop land in danger spots — a 500-year flood plain, an unstable hillside or a historical fire corridor. And in California, aggressive fire suppression has impeded the natural burn cycle in the state’s wooded areas so that there’s more fuel when the massive fires do take hold.

“These kinds of catastrophes have happened and they’ll continue to happen.” Gov. Jerry Brown observed at a news briefing Wednesday. “That’s the way it is with a warming climate, dry weather and reducing moisture.”

California is fortunate to have a governor who understands the perils of ignoring climate change and is aggressively pushing policies to mitigate its future harm. Unfortunately, that puts him at odds with a head-in-the-sand president who blithely disregards the obvious connection between the warming climate and the multiple federal disaster areas he’s been forced to declare in Texas, Florida, Puerto Rico and, now, California.

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