Dale Haidvogel, Mohamed Iskandarani, and Julia LevinWe wish to assess the importance of remote physical forcing on Georges Bank. To do so, we are coupling the Dartmouth Georges Bank / Gulf of Maine model to a basin-scale model of the North Atlantic developed at Rutgers. Though differing somewhat in specific approach (QUODDY uses low-order triangles, SEOM uses high-order quadrilaterals), both are Galerkin-based finite element models for which prior coupling strategies have been developed.
In view of the numerical and dynamical complexities involved, model coupling will proceed in stages. As a first step, we are preparing for a series of simulations in which only barotropic coupling is allowed. External forcing mechanisms to be explored in this first phase include (the depth-integrated influences of) the wind-driven circulation, mesoscale eddies and rings, and tides. Full 3D coupling will be undertaken in a second phase.
In order to expedite model coupling, we have produced a two-layer version of the North Atlantic model. The two-layer version has the advantage of being mathematically simple and computationally fast, while retaining the rudiments of important baroclinic and barotropic processes, e.g., tides, sheared wind-driven currents, baroclinic instability. This fast version of the basin-scale model will be used to efficiently prototype the coupling algorithms.
Here, we review the current status of the basin-scale simulations, and discuss our coupling strategy. Important issues that are still pending include: