Development of a numerical model of tidal and wind-driven circulation in Bass Strait

Abstract

The initial stages of the development of a numerical model to investigate the effects of wind and tidal forcing on the sea-surface height distribution and currents within Bass Strait are described. The hydrodynamical model is based on depth-averaged equations and incorporates the effects of the earth's rotation and variations in bottom topography. Numerical experiments have been performed with the model to determine the response of Bass Strait to two separate forcing mechanisms: stationary fields of uniform wind stress suddenly imposed over the sea surface, and tidal heights specified along the open-sea boundaries of the model. The results of these experiments are presented and discussed, the principal conclusions being that the maximum tidal currents generated are generally larger than those generated by the wind, and that variable bathymetry is a major influence on the flow. Furthermore the tidal motion may be characterized by two Kelvin waves travelling in opposite directions through the strait.