Wildfire risk growing in Northwest
Even too-wet-to-burn areas getting warmer
ISSAQUAH, Wash. — Nestled in the foothills of Washington’s Cascade Mountains, the bustling Seattle suburb of Issaquah seems an unlikely candidate for anxiety over wildfires.
The region, famous for its rainfall, has long escaped major burns even as rising temperatures have driven an increase in the size and number of wildfires elsewhere in the American West.
But according to experts, previously too-wet-to-burn parts of the Pacific Northwest face an increasing risk of significant wildfires due to higher temperatures, lower humidity and longer stretches of drought.
And the region is uniquely exposed to the threat, with property owners who are often less prepared for fire than those in drier places and more homes tucked along forests than any other western state.
In towns across the region, that takes a shape familiar from recent destructive California wildfires: heavy vegetation that spills into backyards, often pressing against houses in neighborhoods built along mountains, with strong seasonal winds and few roads leading out.
“The only thing that’s keeping it from going off like a nuclear bomb is the weather,” said Chris Dicus, a professor at California Polytechnic State University, San Luis Obispo and head of the Association for
Fire Ecology, a national group that studies wildfire and includes experts from the U.S. Forest Service and U.S. Geological Survey.
With historically short summers, the swath of densely forested coastal territory stretching from British Columbia into northwestern Oregon has long been cloaked in a protective veil of moisture.
But rising temperatures are changing the region’s seasons. A national climate assessment prepared by 13 federal agencies and released in
2018 said the Pacific Northwest had warmed nearly 2 degrees Fahrenheit since 1900.
Experts say even a modest increase in contributing factors, like days without rain, could make forests much more prone to burning.
“It’s a couple of weeks’ difference,” said Michael Medler, a fire scientist and chair of the environmental studies department at Western Washington University. “Those are the kinds of changes that amount to taking a forest and pushing it over the edge.”