For weeks, wildfires have raged across Alaska’s vast Southwest region — threatening villages, burning up hundreds of thousands of acres and pushing smoke far across the state.
Fire on the Southwest Alaska tundra isn’t unheard of, but as climate change continues to reshape the state’s environment, tundra fires are becoming both more frequent and more severe.
TheEast Fork Fire, currently burning in the Yukon-Kuskokwim Delta, is the largest fire on record in the area, having burned some 125,000 acres so far, according to Rick Thoman, a climate specialist with the Alaska Center for Climate Assessment and Policy at the University of Alaska Fairbanks.
And of the 700,000 acres burned in Alaska this fire season, most of that has been in the Southwest, said Zav Grabinski, a fire science communication specialist for the Alaska Fire Science Consortium.
That’s unusual since most of Alaska’s fires tend to burn in the state’s Interior boreal forests, between the Brooks Range and the Alaska Range.
The current fires in Southwest Alaska are burning on a landscape marked by permafrost and small vegetation, as well as a lack of trees, Grabinski said.
Tundra fires have always happened, said Nancy Fresco, an associate research professor at the International Arctic Research Center within the University of Alaska Fairbanks, “but climate change is greatly increasing their frequency and severity.”
Historically, fires affecting the Southwest tundra were relatively small and infrequent, she said.
“The fires burning now really are unprecedented in that sense,” Fresco said.
That’s due to several factors. Statewide, Alaska is experiencing higher temperature trends that can cause drying, which in turn can spell more frequent and intense fires.
And on top of that, climate change is causing vegetation in the region to change. With warmer seasons, the soil thaws earlier, and different plants begin to grow there, Fresco said.
In some areas where once not-flammable lichen and moss grew, there might be more flammable grass and shrubs growing instead. So when lightning strikes, it’s more likely to lead to a fire, and a fire that spreads, she said.
Tundra environments are vastly different around the state — in Utqiagvik, there is nothing that grows taller than a person’s calf, while in the Southwest region, willow and alder thickets grow some 10-feet high, Thoman said.
Thoman also noted the western spread of the state’s boreal forest — meaning that over the long term, a tundra fire in Southwest Alaska may just be considered a forest fire, with warmer summers able to support tree growth.
The trend of increasing tundra wildfires isn’t playing out the same around the state. Thoman said the increases are concentrated in tundra areas of Southwest Alaska and in the Noatak Valley, but the Seward Peninsula and North Slope aren’t showing the same uptick, though it’s not clear why.
While Fresco’s fire modeling can’t say where and when future fires will burn in a precise way, she said it points to more severe fire years, particularly in tundra areas.
“It’s extremely difficult to predict exactly when some of those more severe fire years might occur,” Fresco said. “But, certainly for tundra areas, the trend is towards greater risk of fire.”
Fresco said while it can be hard for people to look at research that predicts bad news, there’s a positive side: It empowers people to plan and to ask how communities can get ready, she said.
“It’s important to think about this statewide and to think how larger communities can help and support smaller communities in dealing with risk and then planning for risk,” Fresco said. “Because we’re all in this together.”