Operational oceanographic applications for the Wide Swath Ocean Altimeter

The Wide Swath Ocean Altimeter (WSOA) is an interferometric radar instrument presently being developed by the Jet Propulsion Laboratory for integration to the Ocean Surface Topography Mission. The Naval Research Laboratory has a long history of working with satellite remote sensing instruments and applying the information to ocean environment prediction. Traditional nadir altimeter satellites measure sea level at the satellite nadir point with a footprint of about 7 km at intervals of about 6.5 km along the ground track. While the information is very useful for ocean monitoring and prediction, the limited spatial extent creates a large possibility that ocean mesoscale features such as eddies or current meanders may not be sampled. The wide swath instrument provides a much greater spatial density of measurements. The intrinsic instrument resolution is about 1 km in the across-track direction and 11 km in the along-track direction. The instrument provides measurements within these cells across a 200 km wide swath. Errors levels are high, and averaging to 15 km bins greatly reduces error levels.