11:00 AM - 11:15 AM
[HDS08-08] Slope instability in polar permafrost - dynamics of frozen debris lobes in the Alaskan Brooks Range
★Invited Papers
Keywords:permafrost thaw, slope instability, photogrammetry, tree-ring research, dendrogeomorphology
Our research in teh Alaskan Brooks Range aims to improve our understanding of frozen slope dynamics, an emerging response to climate warming in the Arctic, using monitoring of surface movement and dendrogeomorphology, with a specific focus on frozen debris lobes (FDL) in Alaska. Across the Arctic, rates of mass movements are expected to accelerate in response to warming-driven permafrost thaw, and our proposed research will provide a key long-term perspective to better understand how sensitive FDL processes are to climate warming. Because they are forested features, our long-term reconstruction of FDL dynamics will come from dendrogeomorphology, the use of tree-rings to precisely date and quantify past geomorphic change. This work enhances our understanding of how ongoing climate change will impact FDL dynamics, by defining movement beyond historical records and identifying past episodes of instability over the last several centuries.
The work involves innovative approaches and novel results. There has been relatively limited application of dendrogeomorphology in permafrost terrain. This work is the first to couple photogrammetric and tree-ring analyses to determine 3D surface changes and related tree behavior on landslides in permafrost environments over time. Lessons learned from this research can be applied elsewhere where permafrost-stabilized slopes are prevalent. This includes other forested landslides that threaten infrastructure and management goals in Gates of the Arctic, Denali and Wrangell St. Elias NP and elsewhere within Alaska. This also includes alpine permafrost as FDL are an integrative part of the continuum of slope movement processes in permafrost. While these research results will increase understanding of FDL dynamics, the approaches developed here can therefore be used to determine long-term movement rates and surface dynamics for other FDL-like features within the Arctic, and in more temperate mountainous regions.
The work involves innovative approaches and novel results. There has been relatively limited application of dendrogeomorphology in permafrost terrain. This work is the first to couple photogrammetric and tree-ring analyses to determine 3D surface changes and related tree behavior on landslides in permafrost environments over time. Lessons learned from this research can be applied elsewhere where permafrost-stabilized slopes are prevalent. This includes other forested landslides that threaten infrastructure and management goals in Gates of the Arctic, Denali and Wrangell St. Elias NP and elsewhere within Alaska. This also includes alpine permafrost as FDL are an integrative part of the continuum of slope movement processes in permafrost. While these research results will increase understanding of FDL dynamics, the approaches developed here can therefore be used to determine long-term movement rates and surface dynamics for other FDL-like features within the Arctic, and in more temperate mountainous regions.