An intercomparison of electromagnetic and acoustic current meters in a shallow estuary

摘要

We describe and compare the performance of a well known electomagnetic current meter and two types of acoustic Doppler current meters. Two Aanderraa Instruments DCS35OOs were separated by 84 cm and deployed on a mooring between two Interocean S4sand allowed to collect data for 145 hours in a shallow (10 m depth) site in Eastern Long Island Bound. Contemporaneously, two 300 kHz R.D. Instruments Workhorses were deployed on the bottom 30 m to the north and south of the mooring. The results of the intercomparison experiment showed that:(1)there were intermittent, unreasonably large amplitude spikes in the velocity records obtained by the Dc83500, and (2) that once the data spikes were removed and the vertical shear of the tidal flow has beenaccounted for, the mean difference between the DC83500 and 84 observations was within the range expected.