Field evaluations of a bottom-mounted acoustic doppler profiler and conventional current meter moorings

The performance of a prototype Doppler Acoustic Profiling Current Meter has been evaluated by comparison with state-of-the-art conventional current meter moorings in the Coastal Ocean Dynamics Experiment and also by consistency checks comparing velocities calculated from data from different combinations of acoustic beams. The RDI Doppler profiler generally yeilds high (lower) speeds than moored VMCM's (VACM's). Comparisons with laboratory calibrations of the mechanical current meters suggest that a large portion of the differences observed in the near-surface region could result from mooring motion and self-wake contamination experienced by the mechanical sensors in oscillatory flow.