Simulations of shelf sea response due to travelling storms

Abstract

A layered ocean model has been implemented for the numerical simulation of baroclinic shelf sea response, due to travelling storms. Atmospheric forcing by wind stress and surface pressure gradients is simulated by a circular cyclone model, corresponding to typical extratropical and tropical storms. Both Eulerian and Lagrangian coordinate descriptions have been used. The latter method enables also a more direct tracking of density interfaces, intersecting with the bottom topography. Three test examples have been investigated; storm response on a continental shelf and an escarpment at high latitudes; and the response of a tropical storm at a narrow shelf in low latitudes. The first two examples may simulate typical conditions over northwest European shelves: the latter may simulate hurricane response along the western coast of Mexico and the Gulf of California. The results of the simulations demonstrate typical features of storm response in these shelf regions, as narrow-banded barotropic shelf wave oscillations, near inertial period, and long periodic baroclinic wave modes. The performances of different numerical schemes have been investigated, in order to assess the accuracy of the numerical results.