Cryoreactions and Arctic marine cryospheric chemistry

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A rapidly changing Arctic Ocean is opening up unprecedented opportunities for socio-economic development; associated with these are unparalleled challenges to protect environmental integrity, ecosystem services, food security and the ways of living for Inuit and other Indigenous peoples. My research program pursues fundamental and applied studies on chemical reactions at or below water-freezing temperatures, known as cryoreactions, and their roles in environmental fate and effects of legacy and emerging contaminants in the Arctic in a changing climate. Over the next five years, I propose to characterize and parameterize chemical reactions occurring at temperature, salinity, pressure, pH, redox, and light conditions resembling those of the Arctic marine cryosphere including sea ice, the overlying snow and underlying seawater. The focus will be on mercury from past and ongoing global emissions, oil spills from increasing marine shipping activities in the Arctic, and the coupled bromine-mercury cryophotochemistry as a potential proxy to reconstruct past sea ice variability in the Arctic Ocean. The research methodology will integrate molecular-level studies at a dedicated cryospheric laboratory under fully controlled conditions at the University of Manitoba and field studies across the Canadian Arctic Ocean (e.g., Hudson Bay, Baffin Bay, Beaufort Sea). Bridging between these two scales are mesocosm-scale studies at the Sea-ice Environmental Research Facility in Winnipeg and the newly operational Churchill Marine Observatory in Churchill, Manitoba. Together with geochemical and global climate-mercury modeling studies, the proposed research will put molecular-level understanding of cryoreactions to work to project past, ongoing, and future changes in the temporally and spatially dynamic Arctic marine cryosphere and their implications for ecosystem and human health. The proposed research program will directly train at least 13 highly qualified personnel, including one research associate, one postdoctoral research fellow, three PhD students, three MSc students, and five senior undergraduate students. Cryoreactions and cryospheric chemistry are new scientific frontiers, with great potentials for fundamental scientific discoveries of new reaction pathways and mechanisms at freezing temperatures. The focus on mercury and oil spills is largely driven by my decade-long engagement with Arctic communities from western Hudson Bay to the High Arctic. The improved understanding of cryospheric chemical processes will allow us to improve the projection of Arctic ecosystem recovery from mercury pollution, to manage and respond to the increasing risk of oil spills in Arctic waters, and to better project future sea ice variability. Collectively, they will support policy-making and technological innovations for pollution control and climate change adaptation in the Canadian Arctic and beyond.