Groundwater Dynamics in Changing Cold Regions
Abstract:
Subsurface flow and transport processes in seasonally frozen and permafrost environments are integral components of terrestrial water, energy, and mass cycles. Climate change and associated perturbations to these cycles alters hydrological and ground thermal regimes, changing the timing, magnitude, temperature, and chemical composition of groundwater recharge and discharge. Hydrogeological responses to climate change are imperative to understand in order to quantify feedbacks to climate change, manage water resources, and assess the fate of contamination in cold regions. Characterizing the complex flow and transport processes in these systems remains a major challenge, but an important step toward improved understanding of groundwater in warming cold region landscapes. This presentation focuses on coupled water flow and mass/energy transport in subsurface environments subject to freeze-thaw conditions in both seasonally frozen and permafrost regions. Specific examples will look at the effects of preferential flow on snowmelt infiltration and groundwater recharge in seasonally frozen soils of the Canadian Prairies, and the consequences of permafrost thaw on groundwater discharge and mobilization of chemical species sequestered in Arctic soils. Improved knowledge and representation of these important processes and interactions can greatly improve our understanding of, and ability to predict, groundwater dynamics in cold regions under changing climate, ecosystem, and land use conditions.