Ocean tides can drag the atmosphere and cause tidal winds over broad continental shelves

Oceanic tides lead to some of the largest currents of the world ocean and have important implications for oceanic circulation. In the last decade, the feedback effect of surface currents on the overlying winds has been shown to strongly regulate the ocean circulation. Here we present evidence, using coupled high-resolution ocean-atmosphere simulations and in situ measurements, that ocean tides can drag the atmosphere above. The current-induced tidal winds expand across the atmospheric boundary layer, while dissipating tidal energy. They are likely present in many shelf regions of the world ocean, with an amplitude of about one-third of the underlying tidal currents, i.e., up to 1.5 ms−1. Consideration of surface tidal winds can have implications in areas ranging from climate modeling to wind farming.

Lionel Renault, Patrick Marchesiello