The forced-dissipative linear response is calculated for two-dimensional homogeneous flows on a beta-plane in cylindrical oceans with abrupt shelf topography. Forcing is either windstress or prescribed motion of the upper rigid lid in a horizontal plane, and is harmonically varying in time. Dissipation is restricted to be Ekman damping only. Semi-analytical calculations of the response are compared with their analytical limiting forms of pure planetary Rossby response and pure topographic shelf response, respectively, and with purely numerical two-dimensional finite-element calculations. Solutions without transients are presented for both ocean and laboratory values of basin and topographical dimensions. Forcing profiles considered are oscillating motion of the upper rigid lid, or its windstress analogue, and a meridional windstress localised over the Eastern shelf and zero elsewhere. The reponse to the global forcing in laboratory domains is compared with results from laboratory rotating tank experiments. The response to the Eastern localised shelf forcing is compared qualitatively with suggestive offshore radiation of planetary Rossby modes found in satellite imagery at the U.S. West Coast around 40N.
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12th Conference on Atmospheric and Oceanic Fluid Dynamics