Episodic Events in Coastal Transport in the Keweenaw Current in Lake Superior

A major goal of the NSF-CoOP and NOAA-COP on Coastal Studies in the Great Lakes is to improve the understanding of coastal transport processes at the margins of the Great Lakes. One of the major features in all of the Great Lakes is the Keweenaw Current along the southern coast of Lake Superior. This current is a strong, narrow coastal jet with speeds exceeding 50 cm/sec including both barotropic and baroclinic components. This poster presents wind, temperature and current meter time series, as well as hydrographic sections, from two studies (1972-73 and 1998-2000) describing and comparing episodic coastal transport processes in the Keweenaw Current. The processes and events include both episodic and seasonal weather forcing of vertical and horizontal lake circulation with wind-driven coastal upwelling and downwelling, with heat-driven thermal bar circulation, and with wind-driven and heat driven coastal jets. The data suggests that as much as much as 25% of the lake volumn passes through the current each year, with the majority of the transport occuring in winter.