Circulation, dispersion and hydrodynamic connectivity over the Scotian Shelf and adjacent waters

Abstract

A nested-grid ocean circulation modelling system is used in this study to examine the circulation of surface
waters over the Scotian Shelf and its adjacent coastal water bodies. The modelling system consists of a
coarse-resolution (1/12°) barotropic storm surge (outer) model covering the northwest Atlantic Ocean, and a
fine-resolution (1/16°) baroclinic (inner) model covering the Gulf of St. Lawrence, Scotian Shelf, and Gulf of Maine.
The three-dimensional model currents are used to track trajectories of particles using a Lagrangian particle-tracking
model. The simulated particle movements and distributions are used to examine the dispersion, retention, and
hydrodynamic connectivity of surface waters over the study region. The near-surface dispersion is relatively high over
western Cabot Strait, the inner Scotian Shelf, and the shelf break of the Scotian Shelf. The dispersion is relatively low in
Northumberland Strait. A process study is conducted to examine the physical processes affecting the surface dispersion,
including tidal forcing and local wind forcing. The model results show that the tidal currents significantly influence the
dispersion of surface waters in the Bay of Fundy.