Study: By 2040, We May Expect A Five-Fold Increase In Western US Fires, Avg Temps 4F Higher
From Montana to California, wildfires in 2017 shattered record after record and cost the Forest Service an unprecedented $2 billion. The blazes ravaged rural landscapes and business centers and claimed dozens of lives, including those of at least two firefighters. This season’s bone-dry winter conditions in the southern Rockies could set the stage for another taxing fire season in the West. If it’s starting to feel like the weather pendulum is favoring one side of the extreme, that’s because it is.
Over the next two decades, as many as 11 states are predicted to see the average annual area burned increase by 500 percent, according to a recent study. That would mean a small fire, say 100 acres, becomes, on average, a 600-acre fire, with Idaho, Montana, New Mexico, and Nevada expected to increase 700 percent in burn size. It’s a grim picture for future fire seasons—one that might be inevitable, because researchers have been able to check their work from current trends.
Scientists from the University of Arizona, the Universidad Nacional del Comahue in Argentina, and the University of California, Merced, analyzed more than three decades of fire occurrence, seasonal temperatures, and snowpack trends throughout western North America to calculate how climate regulates wildfire. By 2039, the researchers estimate there will be 50 fewer days of snowpack in much of the West and a four-degree Fahrenheit increase in average temperature. Both trends will create longer fire seasons that burn much more land.
“This model is essentially saying that fire is going to increase a lot in the interior continental U.S. But that’s only true to a certain point. It’s going to stop being true when those forests can no longer support that kind of fire,” says LeRoy Westerling, a professor of complex systems management at the University of California, Merced, and a co-author of the study. When that happens, the landscape is going to look really different. In less than a generation, drought and fires in western North America could reshape some forests into dry scrublands, where only smaller, water-hardy, and fire-resistant trees thrive.
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https://www.outsideonline.com/2289216/20-years-wildfires-will-be-six-times-larger