SYSTEMS MODEL OF COASTAL CIRCULATION

The numerical model presented simulates two-dimensional hydrodynamic conditions in order to predict both components of the average velocity, vertically integrated, as well as the free surface elevation of the sea in coastal waters. The equations supporting the model are the well-known shallow-water equations, or quasi-static equations. In the classical theory for long waves in shallow water, the vertical accelerations of the fluid particles are neglected because these accelerations are very small with respect to gravity. In the same manner, vertical velocities may be neglected when compared with the horizontal ones. Integration of the system of differential equations in partial derivatives has been performed by using a “leapfrog” finite-difference technique under explicit solving. The computer program was developed in FORTRAN 77. Results and their agreement with coastal configuration are shown for two applications of this model: the Delta del Ebro, on the Mediterranean coast of Spain, and the Ria de Pontevedra, on the Atlantic northwestern coast of Spain. Here attention is focused on the application to the Delta del Ebro area.