The eastern boundary current of the south Indian Ocean. It occupies the latitude band of the subtropical gyre but is not part of it; rather, it is found as a narrow and swift southward flowing current along the west Australian shelf opposing the broad northward flow of the subtropical gyre (the West Australian Current) farther offshore. The Leeuwin Current runs against the prevailing wind; it is driven by the alongshore pressure gradient caused by the connection between the Pacific and Indian Oceans north of Australia. Its water, which is of tropical origin, cools as it proceeds southward, producing convection and a continuous deepening of the surface mixed layer along the current's path. The associated heat loss is a significant heat gain for the atmosphere.