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Mid-Atlantic Bight

Mid-Atlantic Bight. Transport over a Long Shallow Shelf. The Shelf. ~ 25m depth at the inner shelf ~ 50m at midshelf ~ 200m at the shelf break, where it then drops rapidly to deep ocean (1 Degree Longitude ~ 85.4km @ 40N) The distance shore to shelf break ranges from 60-200km.

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Mid-Atlantic Bight

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  1. Mid-Atlantic Bight Transport over a Long Shallow Shelf

  2. The Shelf ~ 25m depth at the inner shelf ~ 50m at midshelf ~ 200m at the shelf break, where it then drops rapidly to deep ocean (1 Degree Longitude ~ 85.4km @ 40N) The distance shore to shelf break ranges from 60-200km

  3. Estuaries of the MAB Chesapeake Bay system Delaware Bay Hudson River

  4. Winter Conditions

  5. (Immediately before and during Irene) Summer Conditions

  6. Ekman vs Tilburg Unconventional Upwelling

  7. Tilburg's Model K_M - vertical eddy viscosity K_H - vertical eddy diffusivity Density taken from the Equation of State Salinity is constant Horizontal eddy viscosity and diffusivity are constant K_M terms calculated for surface wind stress and bottom stress given by D L= 65km (width of shelf)

  8. Downwelling and Onshore Transport - Ekman

  9. Downwelling and Onshore Transport - Tilburg

  10. Transport in 3 Dimensions - Wind Stress Wind Stress is the primary mechanism for transport. Integrated continuity equation can be used to demonstrate the surface and bottom stress is directly related to across shore transport while inversely related to along shore divergence.

  11. Transport in 3 Dimensions - Buoyancy as an amplifier Shallow Shelf allows for fresh water intrusions to reach the bottom instead of forming a lens. Supports geostrophic, cyclonic flow of high downshelf velocity. High shear across shore. These intrusions become displaced offshore and mix while the region experiences upwelling at the coast.

  12. Transport in 3 Dimensions - Buoyancy as an amplifier The buoyancy intrusion's flow is driven by stratification gradients (dN^2/dy) creating velocity gradients along shore. Negative gradient indicates convergence with the intrusion upshelf. Positive gradient indicates divergence with the intrusion downshelf. While wind dominates the buoyancy intrusion under strong wind conditions, divergence may still be strong under light wind conditions.

  13. References Across-Shelf Transport on a Continental Shelf: Do Across-Shelf Winds Matter? Tilburg 2003 Three-Dimensional Flow in a Shallow Coastal Upwelling Zone: Alongshore Convergence and Divergence on the New Jersey Shelf Tilburg and Garvine 2003 Additional Images from: RUCOOL glider page http://cmtt.tori.org.tw/data/App_map/Maps_jpg/4_13_Mid_Atlantic_Bight_New_York_Bight.jpg http://ocw.mit.edu/resources/res-12-000-evolution-of-physical-oceanography-spring-2007/part-1/wunsch_chapter7.pdf

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