Effective depth of HF current measurements: observations from COPE-3

Comparison of HF radar measurements of ocean surface current with those from moored acoustic Doppler current profilers (ADCPs) during the third Chesapeake Bay Outflow Plume Experiment during October and November 1997 suggests that the effective depth of the HF radar measurements is between (2k)^-1 and 1.4(2k)^-1, where k is the ocean wavenumber which is in Bragg resonance with the HF wavelength. This is consistent with the analysis of Stewart and Joy [1974] who estimated an effective depth of (2k)^-1 for a linear current profile