Model and Observational Studies of the High Latitude Oceans

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The thematic focus of the proposal is climate and ocean dynamics in the Arctic, Canadian Arctic Archipelago (CAA) and the Labrador Sea. The Arctic and subarctic regions are expected to experience particularly large amplitude changes in response to global warming. Loss of sea ice and melting of continental ice caps are dramatic and the rate of change unprecedented. ******The CAA is a complex network of straits and basins connecting the Arctic Ocean and the Atlantic Ocean. Northern communities across the CAA rely on this coastal environment for transportation and marine resources. It is an oceanographically complex area where the many channels of the CAA form a complex conduit of seawater that flows from the Arctic and the Pacific to the Atlantic, delivering nutrients, contaminants and biota through the CAA and beyond. The CAA will be the largest cryospheric contributor to sea level rise in the next century beyond Greenland and Antarctica.******Using high resolution numerical modelling we ask a pair of questions related to the CAA and the Arctic Ocean. By what channels (and with what specific volume and freshwater fluxes) do Arctic waters flow from the Canada Basin, through the CAA, and into the Atlantic? What will be the fate of the large amount of freshwater stored within the Beaufort Gyre of the Arctic Ocean and how will it impact the CAA? ******The Labrador Sea, off the east coast of Canada, is one of the few oceanic regions where the deep ocean exchanges gases directly with the atmosphere. Localized deep convection releases large amounts of heat to the atmosphere and the resulting Labrador Sea Water contributes to the global ocean thermohaline circulation that redistributes heat from low latitudes to the poles. Stratification changes may come from direct surface warming as well as the enhanced freshwater input from the melting of snow, multi-year sea ice and glaciers in Greenland and Canada. With the accelerating rate of warming in the high North, multiple sources of freshwater now converge on the Labrador Sea, with the potential to disrupt deep convection, meridional ocean heat transport, climate, and ocean biogeochemistry at regional and global scales. ******Using both historical data analysis, as well as high resolution numerical modelling, we ask questions related to the interactions of the Arctic/CAA and the sub-polar North Atlantic. The first key question is how (and how much) will the freshwater being routed from the Arctic Ocean and the Greenland ice sheet be taken up in the Labrador Sea and the sub-polar North Atlantic Ocean? Can we determine if this transport is increasing? Looking at the impact of the sub-polar North Atlantic on the higher latitudes, we also ask what are the pathways for warm Irminger Water in the sub-polar Atlantic and does this warm water mass penetrate into the CAA? Our goal here is to improve our understanding of the transport of oceanic water to and from the fjords that contain major tidewater glaciers.