Remote sensing of ocean surface currents with the Seasonde HF radar

The SeaSonde high-frequency radar is a portable, shore-based system for measuring ocean surface currents in real time over coverage areas exceeding 1000 km2. It utilizes compact antennas and direction finding methods to extract information on currents from the sea echo signals. Experiments with the radar in sheltered coastal waters in Canada and oceanic conditions in the Pacific Ocean have shown reasonable agreement with drifters and current meters. Forecasting methods have been developed that provide estimates of the slowly varying flows produced by tide, wind and buoyancy, and estimates of the spatially varying eddy diffusivity, based on a few days of measurements. These current data are suitable for use in oil spill models.