Abstract
Surface stress-driven coastal currents and upwelling were produced around the outer edge of a cylindrical tank having a conical bottom and a protuberance representing a cape. A large-standing wave formed at a distance Dsw ≈ 2Rcθ0.4*(λs/Rc)0.2 downstream of the cape, where Dsw is the distance between the wave trough and tip of the cape, Rc is the radius of the cape, and θ* = g′h0/u*fλs (where g′ = gδρ0 is the reduced gravity, h0 is the initial depth of the top layer, u* is the friction velocity applied to the top surface of the fluid, f is the Coriolis parameter and λs is the distance of the stationary position of the upwelling front at the surface from the wall of the tank). The extreme offshore extent of this stable wave trough (as seen from particle streaks) was Asw ≈ 3.4Rc. However, at low values of θ* after many rotation periods, the standing wave often grew in amplitude, producing a cyclone which detached from the wave trough.
Unstable baroclinic waves formed at the upwelled front upstream of the cape and drifted toward it. The presence of the cape caused the flow downstream to diverge horizontally, and this absorbed the oncoming baroclinic waves. The upwelled fluid originally within these waves was advected with this flow as it drifted downstream, so that eventually it was distorted by the divergence and formed a thin filament extending a considerable distance offshore. As the filament continued to drift downstream it was distorted by the downstream standing wave and eventually absorbed by it.
