Model Studies of Near-Inertial Waves in Flow over the Oregon Continental Shelf

Abstract

Abstract Two-dimensional, primitive equation model studies of wind-forced flow over a continental shelf Show that, under upwelling conditions, high levels of near-inertial wave energy are found in the interior over the shelf. The regions of elevated wave energy, with maximum wave amplitudes of around ±0.2 m s−1, persist for up to two weeks and have spatial scales of 20–40 m vertically and 5–20 km horizontally. Relatively high dissipation levels are associated with these concentrations of wave energy. When forced with downwelling-favorable winds, model results show very little subsurface inertial energy on the shelf. A comparison of inertial wave propagation using the primitive equation model and a linearized version of the model demonstrates strong dependence on the background flow field. The behavior of inertial waves using the linearized model is completely different: very little subsurface inertial energy is seen on the shelf in either upwelling or downwelling conditions, except where the bottom slope ...