Near-Inertial Waves and their Interaction with Geostrophic Currents
Near-inertial waves (NIWs), i.e. inertia-gravity waves with a frequency close to f, account for about half of the wave energy in the ocean. Mainly forced by wind, NIWs propagate downward into the ocean’s interior. NIWs are ubiquitous in the oceans, superimposed over geostrophic currents. However, it is unclear if they exchange energy with the balanced flow, thus influencing the circulation. Using a two-layer shallow-water model, we investigate this question. We compare our results with those from the Xie & Vanneste (2015) model, which highlights energy transfers from the balanced flow to NIWs potential energy. We find the same result, though via a different mechanism.