New developments in HF radar measurement of ocean waves

HF radars operating at frequencies 3-30 MHz have emerged as powerful tools for the remote sensing of sea-state. HF radar systems have the unique capability of providing continuous monitoring of ocean surface waves and currents over a wide area out to ranges of 200 km from the coast. Measurements of the ocean wave directional spectra obtained with these systems are self calibrating and do not suffer from any directional ambiguities. Such systems should be of enormous value for sea-truthing satellite wave imaging systems, e.g. SAR. In the UK two systems are in use or under development: the OSCR system (Marex Ltd.) is a short range high resolution system developed for coastal current measurement; the PISCES system (Neptune Radar Ltd.) is intended for longer range measurement of both currents and waves. The paper presents wave measurements from both these systems