Upwelling on the south-west coast of Australia—source of the Capes Current?

A series of temperature—salinity and CTD sections off the south-west coast of Western Australia show the presence of cooler water on the upper (<50 m) continental shelf during the summer months, indicative of upwelling in this region. These data are used to investigate the local dynamics in the region and to determine the source of the relatively cool water of the Capes Current. In particular, a CTD transect off Cape Mentelle during early February 1987, in conjunction with CTD transects taken earlier (late January 1987) off Point D’Entrecasteaux and Albany, show that cooler water off Cape Mentelle is generated by localised upwelling during the summer period, forming the source of the Capes Current. A comprehensive data set in December 1994 revealed upwelling over the inner shelf at Cape Mentelle, coincident with the cool, northerly flow of the Capes Current. Estimates of Ekman driven transports show that flushing of the upper continental shelf can occur between 5 and 9 times per summer.