Grant: Discovery Grants Program - Individual

Unprecedented warming and human disturbance has led to substantial permafrost degradation in recent years in organic-covered permafrost terrains, including the arctic and alpine tundra, taiga and boreal regions that characterise vast areas of Canada's north. There remains a lack of understanding of the mechanisms and rates of permafrost degradation, and the influence of the latter on water drainage and storage patterns and processes. As a result, a major challenge of cold regions hydrology lies in predicting runoff dynamically with permafrost thaw. This underscores the need for sound scientific research to provide the knowledge for informed and sustainable management of northern water resources. This research aims to generate this knowledge, and from it produce a new suite of models for predicting the response of permafrost to climate warming and human disturbance so that basin runoff can be more confidently predicted in the context of thawing permafrost. The short-term objectives are: 1) document the change in permafrost distribution over the last half century at the study site; 2) develop conceptual and mathematical models of key hydrological processes, including plot-scale flows and flows among the major terrain types; 3) examine the permafrost response to changes in the overlying tree canopy; 4) identify the key factors controlling the rates and patterns of preferential thaw that may lead to permafrost degradation; 5) develop a new model that simulates the discontinuous and continuous permafrost response to climate warming and human disturbance; and 6) couple the hydrological and permafrost models to predict the spatial distribution of permafrost, and the river flow regime under scenarios of climate warming and human disturbance. The study will be conducted in the wetland-dominated zone of discontinuous permafrost at Scotty Creek, NWT, because of its rich data archive, high concentration of infrastructure and equipment, and local community interest and support. Extensive cost-sharing and data-sharing opportunities with on-going complimentary research projects also make Scotty Creek a logical study site. However, the project results are intended to be transferable to other widely-occurring organic-covered permafrost terrain types.