Vladimir Romanovsky, a permafrost expert at the University of Alaska Fairbanks, had for years watched the active layer freeze completely by mid-January at some 180 research sites in Alaska.

Alyeska Pipeline consultant Mike Mertz provides a look at how the company is coping with thawing permafrost on the Trans-Alaska Pipeline. The Wall Street Journal's Jim Carlton reports.

Thawing permafrost has released so much methane into Esieh Lake near Fairbanks, Alaska that the air above it is flammable. Credit: Katey Walter Anthony/ University of Alaska Fairbanks Biden ...