Rotary Velocity Spectra from Short Drifter Tracks

The authors describe a method utilizing short-duration drifter tracks to compute rotary velocity amplitudes and phases for tidal frequency bands. These are compared to amplitudes and phases from a tidal model, revealing the regions where strong internal tides dominate the observed record or the times when inertial motions compete with the tidal signals. This method therefore enables a direct comparison between Lagrangian drifter data and Eulerian model simulations, while providing information on possible origin and spatial variability of tidal currents.