Ocean Dynamics in the Northwest Atlantic

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The long-term goal of my research program is to understand the physical and ecological dynamics of the Northwest Atlantic through observational and modeling studies. My program has four short-term objectives: (1) to improve our ability to observe the ocean through the development of new sampling systems and new approaches to their deployment; (2) to expand our understanding of tidal and wind-forced dynamics of coastal embayments; (3) to determine the along-shelf transport of heat and freshwater on the Newfoundland shelf and (4) to extend the use of numerical models for the design and operation of field sampling campaigns and to integrate physical and biological data for improved understanding of marine ecosystems. The time scales of interest range from the daily to the seasonal, interannual and decadal. The approach taken in this research involves integrating innovative observational oceanographic studies with advanced numerical modeling. We will use new and developing technologies to improve our ability to sample in the ice-covered waters of the Northwest Atlantic. Field studies will focus on natural laboratories of the Northwest Atlantic including the fjords, coastal embayments and shelf of Newfoundland and Labrador. We will begin by bringing together the historical data for the region, including both physical and biological observations. We will supplement the historical data with new data from dedicated research cruises, mooring and glider deployments on the shelf and in coastal bays and fjords such as Trinity Bay in Newfoundland and Lake Melville in Labrador. The field sampling will benefit from ongoing national and international programs, such as the gas exchange study (Vitals) and the meridional overturning circulation study (OSNAP), both in the Labrador Sea. We will leverage as much as we can from other oceanographic studies. We will use new approaches, integrating gliders and moorings, to measure the along-shelf transport on the Newfoundland shelf. We will address such questions as where does the water come from? And how is it modified on the shelf? Historical data will be used to initialize numerical model runs and to explore dynamical structures of the oceanographic fields, e.g. correlation length-scales, freshwater fluxes, links to atmospheric forcing, the influence of extreme events and seasonal dynamics. Numerical models will be used to integrate the data and to explore key processes that may be confounded in the observations. While there are numerical models that can already be applied, model development will also be an important part of this research program. We will incorporate biological models with the physical circulation models to address ecosystem questions such as how organisms maintain populations in certain regions and how stratification influences population dynamics, with a primary focus on planktonic, passively drifting organisms. The focus of this modeling is on the interaction between simple behavioural dynamics, such as the daily and seasonal vertical migration cycles of zooplankton, with the physical stratification and circulation. The novelty of our work lies in the combination of experimental, and numerical and modeling approaches. Integration of these approaches into a single program will yield a comprehensive interpretation of the role of the critical physical processes in ocean and ecosystem dynamics. Understanding gained from this Northwest Atlantic research, and the instrumentation and techniques developed, will be applied to studies in other regions to develop a more general understanding of the implications of our work.