Grist: To step into the U.S. Army Corp of Engineers Permafrost Tunnel Research Facility in Fox, Alaska just north of Fairbanks is to step back in time. Burrowed into the silt layers of an unassuming hillside, the tunnel is like a scene out of a subarctic Indiana Jones adventure. Shivering, you walk the length of an underground football field, past protruding bones of Ice Age animals (including mammoths) and huge ice wedges, which were frozen in place long before Hebrew scribes compiled the Old Testament....