Residents of the Northwest Arctic might have noticed a low-flying, brightly-colored classic airplane buzzing around. The plane belongs to a German research institute that is mapping remote landscapes, and their goal is to document the effects of rapidly thawing permafrost.
Guido Grosse is with the Alfred Wegener Institute (AWI), a German-based research institute that focuses on polar and marine environments and how they are changing. His research group is flying two classic planes, named Polar 5 and Polar 6. They’re both Douglas DC-3 models — a plane used in early commercial flying, as well as for military campaigns during World War II.
“Yeah, the aircraft is pretty interesting. It's historic. The plane actually was built in 1943. So it's 80 years old,” Grosse said.
The planes are hard to miss, with their bright orange and blue paint job. They also hover at around 3,000 feet, which is about 10 times closer to the ground than most commercial airline flights. But they’re not just flying around for show. Grosse said that the team has retrofitted the planes with new sensors to map how permafrost thaw is changing the landscape.
“We can use any changes at the surface, like erosion, thaw slumping, or lake change, to get a better picture of what permafrost actually does,” Grosse said.
Grosse said that AWI has been involved with permafrost mapping throughout the circumpolar North and Antarctica for decades. Grosse’s group, which consists of an airborne and ground team, has flown out of Kotzebue to locations on the Baldwin and Seward Peninsulas for about five years now. And in that window of time, Grosse said that the researchers have noticed significant changes in permafrost thaw.
“It's getting faster and more dramatic. So there's quite a bit of change,” Grosse said. “We see lake change. Lots of lakes are draining in this region over the last years.”
In 2022, Kotzebue resident Susan Tessier documented a lake at a subsistence camp near Kotzebue that drained over the course of a day after its protective layer of permafrost thawed. Grosse said that these events are becoming more common because permafrost can act like a barrier for Arctic ponds.
“So the water at the surface cannot, like, trickle into the ground very deep, because there's permafrost and impenetrable,” Grosse said. “And once permafrost is thawing out, it might help, like, draining lakes into the ground. Many lakes have disappeared over the last 20 years.”
Grosse said that these changes affect coastlines as well, through something called permafrost thaw slumps. Thaw slumps are similar to landslides, usually originating on hill slopes along the shores of lakes and rivers. Grosse said that thaw slump events can release huge amounts of contaminants and organic material, some of which is thousands of years old and left over from the last ice age. The thaw slumps also usually change the water's chemistry, clouding up marine and river ecosystems and making it difficult for fish species to spawn. Grosse said that recent snowier Arctic winters contribute to the thaw.
“Snow consists by a large part of air, actually. So there's lots of empty space in the snow between the crystals. And so that insulates the ground very well,” Grosse said.
And, Grosse said, when permafrost thaws it often releases greenhouse gases like carbon dioxide, but also more potent gases like methane and nitrous oxide. That’s one thing that Grosse’s ground team is focused on cataloging.
“There are some specific areas in this type of landscape here where they're really strong sources, sort of hotspots of these greenhouse gases,” Grosse said.
Grosse said that it's important to compile information about the changes for the benefit of locals and other researchers worldwide.
“We have this portal that can be used like Google Earth, for example. So you just browse around, and you see the changes as a colorful map. And so we provide some guidelines how to interpret these colors,” Grosse said.
The researchers’ high-resolution global map displays changes in surface elevation, water, vegetation, and coastal erosion. Grosse said that the map’s data can help communities in Alaska plan for how the thaw will affect subsistence activities, or where they can build new infrastructure.
“We have up to date, fresh imagery, basically, that the communities can use for planning, be it housing development, or roads, or whatever,” Grosse said.
Grosse’s research team plans to wrap up their work in the Northwest Arctic in late July.
