Temperatures in Fairbanks have shifted so much that the National Oceanic and Atmospheric Administration officially changed the city’s subarctic designation in 2021, downgrading it to “warm summer continental.” As the climate warms, the ancient ice that used to cover an estimated 85 percent of Alaska is thawing. As it streams away, there are places where the ground is now collapsing. Many of the valley’s spruce trees lean drunkenly and sometimes, only a thin layer of soil covers yawning craters where the ice has vanished. The University of Alaska Fairbanks, home to much of the state’s permafrost research, has itself struggled with recurring sinkholes on its roads and parking lots. “We have invested funding to rebuild,” said Cameron Wohlford, director of design and construction at the school’s facilities, “only to have them fail.” Homeowners around Alaska’s second-largest city are facing expensive repairs, or even having their properties condemned. Hasson eventually traced the river running beneath Lenniger’s property to her neighbor’s, where the owner, Judy Gottschalk, reported that her septic pipes had broken as the ground settled. “My well went out this winter, too,” she said. Not knowing where else the ghost ice lies, Gottschalk has been nervous about putting in a new septic system. The drilling and construction required to replace it would cost her as much as $45,000, more than she originally paid for her house. “Everyone I know is having problems with their housing,” Lenniger said.  As parts of Alaska set record high temperatures in December, Fairbanks closed out 2021 with a destructive ice storm, causing roofs to collapse. A warmer Arctic is also a wetter Arctic, accelerating the breakdown of permafrost, explained Tom Douglas, a senior scientist for the U.S. Army Corps of Engineers’ Cold Regions Research and Engineering Laboratory, in Fairbanks. “For every centimeter of rain, we see about one centimeter of additional top-down thaw,” he said. On average, Fairbanks now sees about five more weeks of rain than it did in the 1970s. The word permafrost, after all, is simply an abbreviation of “permanently frozen ground.” Much of Alaska’s permafrost is tens to hundreds of thousands of years old, first frozen when Goldstream Valley was grazed by mammoths. Now, that sense of immutability is slipping. “It was thought to be permanent — that any changes happened on a scale of tens of thousands of years,” said Vladimir Romanovsky, a professor emeritus of geophysics at the University of Alaska Fairbanks and a leading permafrost researcher.  Many variables influence permafrost’s stability, like how cold it is, how deep it runs, and the quantity of soil moisture, or its “ice richness.” In some parts of Alaska, ice extends nearly a half-mile below the surface, while in others, it has formed the landscape itself, sprouting tundra-covered ice hills called pingos. While the impacts of permafrost thaw — subsidence, flooding, sinkholes, and landslides — mimic the devastation of natural disasters, the Federal Emergency Management Agency isn’t responsible for permafrost damage, and it’s difficult to get covered by homeowner’s insurance. “How fast does a disaster need to move for a department that handles disasters to address it?” Cooke asked.  In 2018, the state recognized a new hazard: usteq, a word from the Alaska Native Yup’ik language that describes the catastrophic land collapse stemming from thawing permafrost, and the erosion and flooding it entails. As sea ice disappears, the coast has been battered by intensifying storm surges, speeding the breakdown of permafrost under the shore. Riverbanks are corroding from thaw, changing everything from the chemistry of the groundwater to its distribution and movement. Permafrost, Henry said, “is linked to everything — our homes, water sources, food sources, vegetation.” researchers usually collect data during the Arctic’s short summer field season, even though winter conditions may look very different, making conclusions less accurate. For instance, recent studies have found that emissions of carbon and methane released by thawing permafrost have been drastically underestimated. There are 1.6 trillion metric tons of carbon currently stored in permafrost — twice what’s now in the atmosphere. New projections suggest that the amount of greenhouse gas emissions from permafrost could equal those emitted from the rest of the United States by the end of the century.......read on      https://grist.org/science/alaska-permafrost-thawing-ice-climate-change/