On Shelf-Slope Water Mass Exchanges Near Washington Canyon and Norfolk Canyon in the Mid-Atlantic Bight
Master of Science (M.Sc.)
Virginia Institute of Marine Science
The physical exchanges between shelf and slope water masses are important drivers of biological productivity in the shelfbreak region of the Mid-Atlantic Bight (MAB). Based on two ocean glider surveys that were conducted in Autumn 2013, and concurrent wind and satellite based sea surface height observations, this study investigates the dynamic mechanisms of wind, surface height variation, water column hydrographic structure, and canyon topography in driving shelf-slope water mass exchanges across the shelfbreak near Norfolk Canyon and Washington Canyon in the MAB. Over the outer shelf, sea surface height variation and wind are important drivers of cross-shelfbreak transport through geostrophic and Ekman mechanisms. Opposing flow in the different layers of the water column leads to shelf-slope water mass exchange. Over submarine canyons, strong upwelling favorable wind in combination with flat sea surface can cause reversed flow along the MAB shelfbreak and thereby induce canyon upwelling of slope water. In addition, the interfaces of shelf and slope water masses are expected to be conducive to double diffusion, which in turn can drive thermohaline intrusions and further enhance shelf-slope exchanges. These shelf-slope exchange processes can contribute to a net salt flux onto the shelf and support enhanced sub-surface primary production in the shelfbreak region
© The Author
Wang, Haixing, "On Shelf-Slope Water Mass Exchanges Near Washington Canyon and Norfolk Canyon in the Mid-Atlantic Bight" (2016). Dissertations, Theses, and Masters Projects. William & Mary. Paper 1539617966.