Selective withdrawl and spin-up of a rotating stratified fluid

Authors present an experimental study demonstrating that rotation has a pronounced effect on currents induced by selective withdrawal of fluid from a density-stratified reservoir. Their observations show that initiating outflow from the reservoir generates Kelvin shear waves. These waves propagate cyclonically around the perimeter of the reservoir, establishing an anticyclonic withdrawal-layer flow. Authors also present a model that describes many features of the spin-up process observed before onset of separation and subsequent gyre formation. The model shows that vertical diffusion of vorticity plays an important role in the spin-up process, leading us to conclude that apparent thickening of the withdrawal layer over time, as seen in changes in the velocity profile, is associated with the vertical diffusion of the spun-up vorticity.