Permafrost thawing. Permafrost thawing is causing the ground to subside 16-33 ft (4.9-10 m) in parts of interior Alaska. The permafrost surface has warmed by about 3.5oF (1.9oC) since the 1960's.
Reference: Osterkamp, T., and V. Romanovsky. 1998. Permafrost monitoring and detection of climate change-comments. Permafrost and Periglacial Processes 9: 87-89.
