A review of ocean current and vorticity measurements using long-range reciprocal acoustic transmissions

Reciprocal acoustic transmissions accurately measure the barotropic and, with suitable ray-path geometry, baroclinic components of ocean currents. Tomographically-derived tidal currents agree with both independent measurements and numerical models. Tomographically-derived currents are inherently range averages. Comparison with point measurements, such as from current meters, nonetheless show satisfactory agreement in all cases. Tomographically-derived, areal-averaged relative vorticity is unique and difficult to verify, but in both the Florida Straits and Gulf Stream regions tomographic vorticity estimates are consistent with current-meter-derived vorticity estimates