Thaw Settlement Hazard of Permafrost Related to Climate Warming in Alaska

Permafrost temperatures have increased in Alaska since the 1960s, and many impacts of climate warming are associated with permafrost thaw. Thaw of permafrost caused by increases in permafrost temperature may result in thaw settlement and significant damage to infrastructure. The goal of this research is to identify regions of Alaska at risk from thaw subsidence related to climate warming and to determine the relative risk of those regions. We developed a Permafrost Settlement Hazard Index (PSHI) by analyzing anticipated climate warming and the ecological characteristics that regulate thaw subsidence. This analysis provides statistical verification that the discontinuous permafrost region is at more risk of thaw settlement than other regions of Alaska. In addition, it estimates future thaw subsidence risk in Alaska in 2050 using future temperature increases projected by published climate models. Results indicate increased thaw subsidence risk in northern Alaska in 2050, with the greatest increase expected in parts of northwest Alaska. However, in the interior and southwest Alaska, projected disappearance of permafrost from the surface will reduce the risk of thaw subsidence.