NASA Researchers Tour Permafrost Tunnel Near Fairbanks, Alaska

FAIRBANKS, ALASKA - MAY 03: In this image released on May 17, 2023, Roots of formerly buried grasses are visible as NASA SnowEx campaign researchers and pilots tour the Permafrost Tunnel Research Facility, which contains 18,000 to 43,000-year-old carbon rich specimens from the last ice age, on May 3, 2023 near Fairbanks, Alaska.The facility, one of the only places on the planet where researchers can walk inside the frozen earth, is operated and maintained by the U.S. Army Cold Regions Research and Engineering Laboratory (CRREL) for use by permafrost researchers worldwide. Permafrost in the Arctic region is melting at an accelerating rate, causing ground subsidence and the release of greenhouse gases and long-lost microbes. Around 25 percent of North America’s exposed land surface is covered in permafrost, according to the National Snow and Ice Data Center. NASA's multi-year airborne and field SnowEx campaign is focusing on boreal forest and tundra regions of Alaska in 2023, their final year. (Photo by Mario Tama/Getty Images)