"Massive ground ice in the western Canadian Arctic: Distribution, origin, age and role in past, present and future landscape change."

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Over the last few decades, permafrost temperatures have increased across the Arctic in response to the 20th century climate change. Ice-rich periglacial environments, where the upper part of permafrost may be 70-90% water by volume, are inherently unstable and may undergo substantial geomorphic modification as landscapes adjust to changing climate. In these regions, the development of thaw slumps is one of the most dramatic manifestations of degradation of ice-rich permafrost. The thaw slumps are already causing impacts on terrestrial and aquatic ecosystems and are becoming a major concern for local Arctic communities. It is expected that the increasing number and size of thaw slumps will have major hydrogeomorphic consequences. This proposal is divided into a series of interrelated projects: 1) Investigating the distribution, growth and stabilization rates of thaw slumps; 2) Determining origin, age and habitability of ice-rich permafrost by developing new and expanding current techniques for occluded gases measurements in ice; 3) Quantify the impacts of thaw slumps on hydrogeomorphology - the emergence of the "degrading massive ground ice fluvial regime. Overall, this research program will involve the training of 11 highly qualified personnel in field-based multi-disciplinary periglacial studies. The results of the proposed research program will greatly increase our knowledge about the distribution, characteristics and age of massive ground ice in western Arctic Canada. This information is essential for: 1) determining the relation between ice-rich permafrost, regional Pleistocene glacial limits and surface geology; 2) assessing the response of ice-rich permafrost to the last time that the Arctic was warmer than current conditions; 3) understanding the potential drivers of thermokarst processes, in particular in relation to growth and stabilization of thaw slumps; 4) assessing the hydrogeomorphic impacts of thaw slumps in the landscape; and 5) predicting regional hydrogeomorphic responses of ice-rich permafrost landscape to future climate change.