COMPARISON OF THE SEMTNER AND CHERVIN EDDY-RESOLVING GLOBAL OCEAN MODEL WITH LUCIE AND SATELLITE-OBSERVATIONS IN THE LEEUWIN CURRENT REGION

Output from the Semtner and Chervin eddy-resolving global ocean genera l circulation model is compared with observations from the Leeuwin Cur rent Interdisciplinary Experiment (LUCIE) and satellite data for the c oastal waters of Western Australia. The model output is a snapshot ove r the domain 9-43 degrees S, 90-120 degrees E for a day in mid July 19 87, which is during the season that the Leeuwin Current is expected to be well established along the western and southern coasts of Western Australia. Maximum Leeuwin Current velocities in the model are of the order of 60 cm s(-1) and are found in the southern part of the current on the western coast and around into the Great Australian Eight. At d epths below about 200 m, and centred near 400 m, there is an equatonva rd-flowing undercurrent with maximum velocity of order 25 cm s(-1). Co mparison of temperature and salinity cross-sections with LUCIE observa tions reveals that the model output for this day exhibits many realist ic features. In particular, the model fields display a number of promi nent meanders and eddies on the Leeuwin Current as well as further off shore. Consistent with observations, mesoscale features associated wit h the Leeuwin Current are concentrated between 25 degrees S and the Ca pe Mentelle region; the flow in the northern part of the Leeuwin Curre nt and the North West Shelf may be too weak to induce eddy-generating instabilities. Prominent in the model output are two large meanders on the Leeuwin Current between 25 degrees S and 29 degrees S and two ant icyclonic eddies further downstream; features similar to these are evi dent in satellite data during winter 1987.