Canadian scientist Philip Marsh and I were flying along the coast of the Beaufort Sea, where the frozen tundra had recently opened up into a crater the size of a football stadium. Located along the shoreline of an unnamed lake, the so-called thaw slump was gray, muddy, and barren, in sharp contrast to the brilliant russet and gold of the surrounding autumn tundra. These retrogressive thaw slumps, or landslides — formed as warming temperatures rapidly thaw permafrost — are increasing across the Arctic, including the kilometer-long, 100-meter-deep Batagaika Crater in the Yana River Basin of Siberia.
The tundra of the western Canadian Arctic has long been carpeted in cranberries, blueberries, cloudberries, shrubs, sedges, and lichen that have provided abundant food for grizzly bears, caribou, and other animals. Now, however, as permafrost thaws and slumping expands, parts of that landscape are being transformed into nothing but mud, silt, and peat, blowing off massive amounts of climate-warming carbon that have been stored in the permafrost for millennia. If this had happened in an urban area, it would have resulted in dozens of buildings being swallowed up. If it had happened along a pipeline right-of-way, it might have resulted in an environmental disaster.