Alaska landslides—A challenge for the Last Frontier

Alaska is the largest and arguably most geomorphologically diverse state in the union, as well as being the most sparsely mapped and poorly understood. While slope instability features are abundant and obvious on the landscape, only a handful have been documented due to the huge area, low population, and unique remoteness of most of the state. Alaska’s climate and complex geology result in landslide trigger mechanisms that may be uncommon in other parts of the country, including permafrost degradation, glacial retreat, earthquakes, and isostatic rebound. In particular, increases in landslides in Southeast Alaska, including potential tsunami-producing events, can be attributed to retreating glaciers, thawing permafrost, and increased precipitation. This talk will provide a brief overview of representative slope failures in Alaska, take a deeper dive into the deadly 2015 Sitka and 2020 Haines landslides, and conclude with a progress report on the efforts and challenges to standing up a dedicated landslide hazard program for Alaska.

Stevens D (2022) Alaska landslides—A challenge for the Last Frontier, 20 April 2022.