Dynamic and thermodynamic processes of snow covered sea ice

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The Arctic icescape is transforming rapidly from one dominated by a perennial to a seasonal sea ice cover.  The summer minimum extent of Arctic sea ice has declined by 50% since the earliest satellite records, with a record minimum in September 2012.  These changes have significant implications throughout the Arctic ocean-sea ice-atmosphere (OSA) interface, and through teleconnections to lower latitudes of our planet.  The impacts of changes in the areal extent, thickness and circulation of sea ice are varied and significant throughout most components of the physical, biological, and biogeochemical aspects of the Arctic marine environment.  There are also many climate related issues affecting indigenous use of the icescape and safe operation of maritime industries now jockeying to develop newly accessible resources in the Arctic.  My long-term objectives are to understand how the atmosphere and ocean affect sea ice dynamic and thermodynamic processes; to predict future changes in sea ice based on this knowledge; and to examine the consequences of this change on various aspects of biogeochemical cycles operating across the OSA interface.  To accomplish this I intend to examine these interacting systems at a range of space and time scales, taking advantage of in situ experimentation, model development and a cycle of hypothesis formation, testing and reformulation. Over the course of this NSERC grant I intend to examine four short-term objectives: 1) Macro-scale - Examine the role of regional to hemispheric scale oceanic and atmospheric forcing of sea ice dynamic and thermodynamic processes. 2) Micro-scale - Investigate the exchange processes at the micro- to local-scale of mass and energy across the OSA interface with a particular emphasis on high frequency atmospheric and oceanic events. 3) Technology - Develop techniques to estimate the geophysical and thermodynamic state of the snow/sea ice system using microwave scattering and emission observations, electro-thermophysical, forward and inverse scattering models. 4) Ecosystem - Examine the nature of sea ice as a habitat over a range of trophic levels combining knowledge from objectives 1 and 2 (above) using technology developed in objective 3. I will address the objectives of this proposal using a combination of field experiments, mesocosm research, modelling experiments, and electromagnetic (EM) interaction studies.  I plan to conduct annual sea ice field programs that are land-based, located on both mobile multiyear and landfast first-year sea ice, and from our research icebreaker (NGCC Amundsen).   The multidisciplinary nature of our field teams allows for a true ‘systems approach’ to understanding how the Arctic ice cover is changing and to work with biologists, geochemists and oceanographers to understand the impacts of observed changes in sea ice on various elements of the marine ecosystem.