| Summary: | Shallow lakes and ponds may cover up to 40 percent of the land surface in Arctic lowland regions. Many of these water bodies traditionally freeze solid during the winter, preserving sub-lake permafrost and keeping soil carbon stocks immobile at depth. Slightly deeper lakes maintain some liquid water beneath floating ice, causing deep thaw zones in otherwise continuous permafrost. Evidence suggests that thinner ice growth in response to warmer, snowier winters is pushing many bedfast ice lakes to floating ice regimes. If such a regime shift becomes pervasive across lake-rich landscapes, resulting permafrost thaw and enhanced moisture and heat flux could generate positive feedbacks, further amplifying this regime change. This project examines the extent and dynamics of bedfast and floating ice lakes in relation to hypothesized interactions and feedback with permafrost and climate. A combination of remote sensing, field monitoring and geophysical measurements, experiments and physical models are used to isolate processes, quantify interactions and project changes. Project findings will be relevant locally for native village subsistence and for water supply to the petroleum industry, and globally for scientists studying permafrost thaw and Arctic climate change.
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