Active-layer detachment failures and the vulnerability of infrastructure in Alaska and northwestern Canada

As the Arctic warms at nearly four times the global average, the thawing of ice-rich permafrost is destabilizing the ground and amplifying thermokarst-related mass-wasting events, including active-layer detachment failures (ALDs). ALDs are translational landslides that occur during summer thaw and are very common across the Arctic in both continuous and discontinuous permafrost areas, most typically in ice-rich unconsolidated sediments. These events are becoming increasingly common and pose significant risks to the region's topography, vegetation, hydrology, infrastructure integrity, and carbon exchange. This study investigates the susceptibility of ALDs in permafrost regions under current climate conditions, with a particular focus on Alaska and the Northwest Territories of Canada. Using the Maxent statistical model, we developed a susceptibility map for ALDs across the study area, providing valuable insights into the spatial distribution of ALD-prone zones. Our analysis revealed high-susceptibility regions in critical areas, including the Brooks Range, Franklin Mountains, and West Crazy Mountains in Alaska, as well as the areas around Dawson City and Mackenzie River regions in Canada. A particular concern is the vulnerability of linear infrastructure, with significant portions (39% in total) of roads and pipelines located in high to very high susceptibility zones. These findings underscore the broader implications of climate change in the Arctic regions, particularly the destabilization of permafrost. They highlight the necessity of adapting infrastructure and management strategies to mitigate the growing risks associated with ALD events.