A Three-Dimensional Model of Tides and Surges in the Great Australian Bight

A three-dimensional spherical co-ordinate tide and storm surge model has been forced on the open boundary with the five major tidal constituents (O₁, K₁, M₂, S₂ and M₃) of the Great Australian Bight to investigate the tides and currents therein. The model has also been used to compute the surge produced by the passage of a 11–13 April 1996 storm with the aim of determining whether the surge observed at Thevenard was due to the amplitude of surge which passed Esperance or due to meteorological forcing.

Sea level data were available at Esperance, Thevenard and Port Lincoln, with meteorological data available in the form of diagrams of isobars. These were used to derive variable pressure and wind fields, and combined with the surge which occurred on the western model boundary at Esperance and the south-eastern model boundary near Port Lincoln. Excellent agreement between modelled and recorded surge at Thevenard was found.