ON THE GENERATION OF SEAMOUNT-TRAPPED WAVES

A model is presented for the excitation, by ambient currents, of subinertial frequency motions over a seamount. Continous density stratification, bottom friction and linear f-plane dynamics are assumed. For the case of a horizontally uniform ambient flow, the first few seamount-trapped wave modes are clearly excited, but more complex (lower frequency) modes are not generated because of frictional damping. For a horizontally-sheared ambient flow, resonances are less obvious, and the low-frequency response is dominated by flow having no azimuthal variations. In all cases, responses are strong enough that it seems likely that seamount-trapped motions often will be observable in nature. © 1990.