Topical Collection: Hydrogeology of a cold-region watershed near Umiujaq (Nunavik, Canada)

A cold-region watershed located in the discontinuous permafrost zone near Umiujaq (Nunavik, Canada) was studied in order to increase understanding of the subarctic water cycle and permafrost dynamics. This essay gives an overview of the research, summarised in a collection of six papers that: respectively characterize the physical three-dimensional cryo-hydrogeological system, present a detailed water balance of the watershed, characterize groundwater and surface-water hydrogeochemistry, describe the application of a tracer method to determine groundwater fluxes, develop a two-dimensional numerical model identifying impacts of groundwater flow on permafrost dynamics, and present a parameter sensitivity analysis. The work serves as a guide for developing site characterization plans at similar permafrost-impacted sites and for evaluating their groundwater resource potential.