Spatially-averaged velocity from the seafloor horizontal electric field

The theoretical relationship between the horizontal electric field (HEF) and the vertically integrated, conductivity-weighted horizontal water velocity, including the effect of finite electrical conductivity beneath the seafloor, is reviewed. This is validated by comparing data from a six-element taut current meter mooring to nearby HEF data collected in 1986-7 in the central north Pacific. The similarity of the two data sets is limited only by a high noise level in the mooring data due to rotor stalling and by large vertical wavenumber components of the velocity field that cannot be resolved with a small number of discrete velocity samples. The results of this study constitute further verification of the utility of electric field methods in oceanography