Hydrological processes and freshwater availability

Unprecedented warming and human disturbance in the zone of discontinuous permafrost has led to substantial permafrost thaw in recent years. This has the potential to greatly alter the nature of water cycling within, and the volume and timing of runoff from the wetland-dominated drainage basins that characterise much of the discontinuous permafrost zone in the Northwest Territories (NWT) and elsewhere. The uncertainty regarding the mechanisms and rates of permafrost thaw, the impact of this thaw on water drainage and storage patterns and processes, and appropriate mitigation strategies, underscores the need for scientific research to provide the knowledge base required for informed and sustainable management of this resource. In response to this need, much of our research is focussed on developing a new suite of models for predicting the response of discontinuous permafrost to climate warming and human disturbance (e.g. from oil and gas exploration, forestry, mining) and the consequent change in landcover and river flow regime in the Taiga Plains. This is being achieved by 1) developing new conceptual and mathematical models of water flow and storage processes; 2) developing a new permafrost thaw model that includes the effects of human-induced disturbances, and feedbacks from thaw-induced changes in ecology; and 3) by coupling the hydrological and permafrost-thaw models to predict the spatial distribution of permafrost and river flow regimes under possible scenarios of climate change and human-induced disturbances.