Meteorologically forced subinertial flows and internal wave generation at the main sill of the Strait of Gibraltar

The generation of large-amplitude internal waves in the Strait of Gibraltar is a widely known phenomenon. Those waves are produced by the interaction of barotropic tidal flow with the main sill (Camarinal Sill) topography and the stratified water column. That interaction primarily causes internal tides that evolve, by non-linear processes, into large-amplitude (more than 100 m) internal waves exhibiting much shorter oscillation periods than those related to the basic tidal variability. Recent observations have shown that on many occasions large-amplitude internal wave generation is dependent on the state of the subinertial flows, which are basically driven by the atmospheric pressure fluctuations over the Mediterranean. Therefore, depending on the meteorological situation over the Mediterranean, internal wave events may be inhibited or activated.