The vulnerability and resilience of continuous permafrost systems to climate change

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Despite a well-documented warming trend in Arctic climate and a corresponding increase in permafrost temperatures there remains tremendous uncertainty about the response of high Arctic permafrost systems to climate change. Several model-based studies suggest widespread terrain instability, melting and disappearance of permafrost, while other field-based studies indicate that permafrost systems may be more resilient than modeling scenarios imply. Generalizations concerning permafrost response to climate change can result in errors in estimates of carbon fluxes and landscape change. There is an urgent need for empirical observation of heat and moisture fluxes for the active layer and the upper part of permafrost to better constrain current models. The current proposal focuses on the vulnerability of key high Arctic permafrost systems on Ellesmere, Axel Heiberg and Herschel Islands to climate change by focusing on thermodynamic processes in the active layer, at the active layer permafrost interface, in ice wedge systems, landscapes underlain by massive ground ice and areas of ephemeral surface ice. By making detailed measurements of boundary layer climate, surface temperature, temperatures through the active layer into permafrost, and mass and energy fluxes through the active layer and at the permafrost table coupled with observations on seasonal snow depth and distribution patterns, vegetation and small scale topographic changes for a range of geo-ecosystems (ice wedges, wet lands, ice-cored surfaces, polar desert and tundra) will contribute a better understanding about the dynamic relationship between climate inputs and permafrost response. Once widespread thermokarst begins permafrost systems become highly unstable. The progressive nature of thermokarst results in very long periods (decades) of terrain instability that will affect virtually all northern activities (transportation, community infrastructure, resource development. These changes will have a profound impact on Canada, as a northern nation with roughly 50% of it area underlain by permafrost we need to be at the forefront of research on permafrost vulnerability.