An evaluation of wave parameters measured using a single HF radar system

The interpretation of high-frequency (HF) radar backscatter from the sea surface to provide measurements of waves, winds, and currents has been developing over the last 30 years. Dual radar systems are usually used because it is then possible to resolve direction and amplitude ambiguities in wave and wind measurement and provide full vector surface currents. In this paper the accuracy and limitations of wave measurements with single radar systems are explored using data sets obtained in a number of experiments using dual radar systems. It is shown that single radar estimates of significant wave height, mean wave period, and wind (or short wave) direction provide two alternative estimates, neither of which is as accurate as a dual radar estimate. Furthermore, there appears to be no way of selecting which of the single radar estimates is correct without bringing in additional information not provided by the radar itself. It is suggested that single radar systems could be used through assimilation of the data into models or a combined wave and backscatter model approach.