A DIAGNOSTIC BAROTROPIC FINITE-ELEMENT OCEAN CIRCULATION MODEL

The finite-element method possesses many advantages over more traditio nal numerical techniques used to solve systems of differential equatio ns. These advantages include a number of conservation properties and a natural treatment of boundary conditions. The method's piecewise natu re makes it useful when dealing with irregular domains and similarly w hen using variable horizontal resolution. To take advantage of these p roperties, a finite-element representation of the linearized, steady-s tate, barotropic potential vorticity equation is developed. The Stomme l problem is used as an initial test for the model. A fourth-order edd y viscosity term is then added, and the resulting problem is solved in both simply and multiply connected domains under both slip and no-sli p boundary conditions. The beta-plane assumption is then relaxed, and the model is reformulated in spherical coordinates. A realistic geogra phy and topography version of this model is also used to examine the b arotropic circulation in the North Atlantic Ocean. Results are found t o agree very well with those of previous diagnostic calculations. In p articular, the Gulf Stream separates at the correct latitude with the inclusion of the JEBAR (joint effect of baroclinicity and relief) term .