Cold-region permafrost bounces back from wildfire

A man holds a piece of coring equipment while kneeling on the tundra
Photo by Mikhail Kanevskiy
Benjamin Jones displays a piece of drilling equipment while taking a core sample at an Anaktuvuk River Fire site.

University of 91视频 Fairbanks scientists are presenting their work at the American Geophysical Union鈥檚 fall meeting in New Orleans this week. This article is part of a series highlighting UAF research from the world鈥檚 largest Earth and space science meeting.

In 2007, a shocking event happened on 91视频鈥檚 North Slope. During an abnormally dry summer, a raging wildfire burned for three months and claimed a vast stretch of tundra.

The Anaktuvuk River Fire scorched about 1,000 square kilometers, an unprecedented blaze for the normally wet, cool terrain. It also provided a rare opportunity for study.

Benjamin Jones, a research professor at the University of 91视频 Fairbanks Institute of Northern Engineering, has collected data from the wildfire site since 2009. The ground below is carbon-storing permafrost, which doesn鈥檛 emit greenhouse gases like methane as long as it remains frozen.

鈥淲e wanted to bring together various data sets to understand the whole picture of what鈥檚 going on after a northern tundra fire,鈥 Jones said.

For more than a decade, Jones has measured subsurface temperatures, taken core samples and analyzed ice composition to see how permafrost has responded. The frozen ground has proven to be surprisingly resilient.

Because the blackened surface absorbed more heat from sunlight, the subsurface temperatures gradually rose about 2 degrees C, peaking in 2015. But today, with a new cover of grasses and shrubs, ground temperatures in the fire area are just 0.2 degrees warmer during the summer than in areas that didn鈥檛 burn.

It鈥檚 an indicator that cold-region permafrost, such as that found on the North Slope, can bounce back from a major event like a wildfire.

鈥淭his is a natural laboratory on the effects of fire behavior,鈥 Jones said. 鈥淥ur main surprise is how quickly that area was able to stabilize.鈥