Detection of nearshore topographic eddies and wakes over a macrotidal coastal region: The influence of tidal currents on its generation

Abstract

Eddies behind headlands and islands may contribute to increasedaggregation and dispersion of organisms. A regional numericalmodel is used for the first time to associate tidal currents withstructures detected in a coastal region of Patagonia, using opticaland microwave images. Vortex diameter, vortex distance to itspoint of origin, and separation of vortices in a vortex dipole, donot exceed 10 km. In addition, CTD profiles are analysed to detectthe influence of an island in the dynamics. A slight influence in thelee of the island was observed in spring 2017. A dimensionlessparameter considering the size of the island and the intensity oflocal tidal currents suggests that instabilities as eddies could beshed from the lee of the island.