Published Aug 14, 2023

Using the longest snow manipulation experiment in Arctic Alaska, new research led by UArctic Research Chair, Jeff Welker of the University of Oulu (UOulu) and Dr. Claudia Czimczik of the University of California, Irvine, report that deeper snow, has led to permafrost thaw and thus the release of ancient C into the modern atmosphere. This amplification of C emissions taking place throughout the year may accelerate the progressive increase atmospheric CO2 levels, global warming and changes in weather and climate of the north and beyond.



Until now, climate change computer models that help groups like the Intergovernmental Panel on Climate Change forecast different climate change scenarios do not take emissions from permafrost into account because those emissions are hard to quantify. But, Drs. Pedron, Jespersen, Welker and Czimczik built sensors (deep soil wells and passive CO2 traps) at the University of Alaska Anchorage and at UC Irvine and installed the new technology allowing them to measure and capture the carbon emissions at their field site in Arctic Alaska. “We can even see the ancient carbon emissions during the summer,” which is when snow depths ought to be at their lowest levels” said Drs. Pedron and Jespersen.

Current climate change is causing snow and ice to retreat across much of the Arctic. But the same warming driving the retreat is also driving increased evaporation and, therefore, precipitation in certain regions. The deeper the snow gets, the more heat the snow traps in the soil each autumn when a blanket of snow covers the landscape. This causes the upper layers of the permafrost to thaw, which allows microorganisms to consume the thawed organic matter and, in the process, release planet-warming gases.

“Permafrost emissions are going to start earlier than we expected in most of our models,” said Czimczik. “We have an opportunity to control the emissions that are under our human control, otherwise these are going to further derail us from our climate mitigation targets.”

Published Aug 13, 2023 by Anna Canny, KTOO

Annual glacial outburst floods on Juneau’s Mendenhall River will continue for years to come. But forecasting the severity of those floods is proving to be an unsolvable problem.

Three scientists shuffled across the vivid blue ice of the Mendenhall Glacier, following a silty channel carved between a steep mountain slope and the glacier’s edge. They wove around dripping, house-sized blocks of ice, heading toward a trail near the mouth of the channel.

An icy chute 10 feet deep sits slightly downhill, at a precipice high above the glacier’s terminus. Three days earlier, a torrent of water had carved the chute after forcing its way through the ice dam that holds water in Suicide Basin — the source of the flood and the place where the scientists were going.

The water then ran down to Mendenhall Lake and spilled out into the Mendenhall River, which rose nine feet in a matter of hours. It was the worst glacial outburst flood in Juneau’s history.

The scientists began a steep ascent up the face of the mountain, scrambling over loose boulders to the lip of Suicide Basin. Moving away from the blue expanse of the glacier, they stood at the edge of a deep, bowl-shaped valley, dwarfed by three steep peaks surrounding it.

Before the flood, this valley had been filled to the brim with 13 billion gallons of water. Now it was empty.

The team’s leader, University of Alaska Southeast hydrologist Eran Hood, peered down at the jumble of ice lining the bottom.

“This is crazy. I’ve never seen it collapse down so far,” Hood said. “I think something has fundamentally changed.”

There were just a few gray-green pools of meltwater at the bottom. But dark high-water marks stained the rock face more than 1,000 feet up, evidence of the water that had accumulated here for months before emptying suddenly.

For decades to come, the neighborhoods downstream in Juneau will be at the mercy of the ever-changing basin. Hood and his team went up to learn more about how, precisely, the basin is changing — and about what those changes might mean for future floods in Juneau.

Published Aug 12, 2023 by Bostin Christopher

A follow-up and discussion on the recent Mendenhall River Flooding covering what happened, what's next, and resources for affected community members Juneau

August 11, 2023 — Full Episode

On today’s program:

• A panel discussion about the recent flooding on the Mendenhall River with Incoming City Manager Katie Koester, University of Alaska Southeast Professor of Environmental Science Eran Hood, and KTOO Climate and Weather Reporter Anna Canny.
• For a list of resources, visit: https://www.ktoo.org/2023/08/09/floodresources/
• For a direct link to the City and Borough of Juneau Flood Response, visit: https://juneau.org/manager/flood-response

Published Aug 11, 2023 by Theo Greenly, KUCB News

Coastal Alaska is on the front lines of climate change. Extreme weather events like Typhoon Merbok that pummeled western Alaska last fall are becoming more common. And many communities along Alaska’s shores are wondering if the future will bring more of the same.

The Arctic Coastal Geoscience Lab at the University of Alaska Fairbanks has spent the last four years trying to answer that question — what storms might look like in the future. They’re doing that by looking into the past.

“You’ve often heard that story that the past is the key to the future,” said Chris Maio, the lab’s director. “And so in geology and understanding coastal changes, we’re really looking into the past through sediment cores.”

Sediment cores are cylindrical sections that scientists extract from the earth’s crust. The UAF researchers use a piston core to insert a long pipe into the seafloor and pull out a tube of earth, which displays the varying strata.

Under normal conditions, the sediment in bays and fjords around the Aleutians is very fine-grained, like silt or mud. But when a storm comes in, it churns up the ocean and moves larger sediment.

Scientists can see those layers in the core and use radiocarbon dating to determine when an event occurred.

Reyce Bogardus has worked alongside Maio since the project’s beginning in 2021. He described it as a sort of timeline of major storms in the Bering Sea.

“We’re building an archive of storminess,” Bogardus said. “The crux of the project is to extend our record of storms in the region — we’re trying to get at storminess thousands of years in the past to learn about the future.”