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Firefighters in Colorado are battling explosive wildfires at a time of year when things are normally quieter. As NPR's Lauren Sommer reports, climate change is extending the fire season across the West.
LAUREN SOMMER, BYLINE: Mike Morgan is using the word unprecedented a lot this year. And that's after a 30-year career in firefighting.
MIKE MORGAN: This year's just been unbelievable. We're just seeing fire growth just like we've never seen before.
SOMMER: Morgan is director of the Colorado Division of Fire Prevention and Control. The largest and now second-largest largest fires recorded in state history are still burning. Normally in October, cool, wet weather is tamping down the fire season.
MORGAN: Most of our folks are usually trying to use up their vacation time to go hunting right now, and they're all out fighting fires.
SOMMER: When Morgan started his career, fires in Colorado's high-elevation forests didn't spread much. The warming climate has helped change that.
JOHN ABATZOGLOU: Unfortunately, none of this seems like a surprise.
SOMMER: John Abatzoglou is a climate scientist at the University of California, Merced. He says most of the West is in a drought right now, and hotter temperatures make it worse by drying out the vegetation even more.
ABATZOGLOU: That's really sort of extending the fire season out and allowing fires to burn longer in places they don't typically burn this time of the year. It's sort of testing out what we sort of traditionally have thought of as in terms of fire season.
SOMMER: Wildfires are also happening in places where they're not common, like the damp forests of the Pacific Northwest. Erica Fleishman is a professor at Oregon State University.
ERICA FLEISHMAN: So historically, they've burned roughly every couple of hundred years. It takes really extreme conditions for those forests to burn because they are so wet.
SOMMER: This year, conditions have been extreme. But even in years with a normal amount of precipitation, climate change can still extend the fire season - more rainfalls instead of snow, which means a smaller snowpack that melts sooner, providing less runoff through the spring and summer.
FLEISHMAN: All of that means that the same amount of water is not available to plants or soils for as long. So that exacerbates the drought. And all of that is projected to unfortunately continue happening as climate continues to change.
SOMMER: Fleishman says the lesson is that communities need to prepare by clearing flammable brush, improving houses and preparing evacuation plans because wildfires will keep happening at times and in places where you don't expect them.
Lauren Sommer, NPR News.
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