Simultaneous CODAR and OSCR Measurements of Ocean Surface Currents in Monterey Bay

Presently, three Coastal Ocean Dynamics Applications Radars, or CODARs, which are ocean surface current measuring radars, are operated around Monterey Bay, California and provide data hourly to an ONR-funded real time environmental monitoring system operated through UC Santa Cruz known as REINAS. CODARs operate using Bragg scatter of high frequency (HF) radio waves from the sea surface to infer radial surface currents. They use direction finding techniques applied to compact, co-located antennae to determine the bearing angle of the measurements. During 4-8 May 1995, a pair of high frequency radar units called Ocean Surface Current Radars, or OSCR’s, were deployed within close proximity of two CODAR systems. Unlike the CODAR units, OSCR units rely on standard beam forming techniques using a long ( 80 m) phased array to determine bearing angle. The purpose of this demonstration was to highlight the capabilities of the OSCR systems. The presence of the CODAR network also provided a unique opportunity to compare measurements from the two types of HF radars to each other and to the suite of in situ instrumentation available in the Monterey Bay area. This study focuses on comparisons of radials measured from each radar system along the corresponding radar baselines and comparisons of radial measurements from each radar site to the near-surface ADCP measurements.