Operational Altimeter-Derived Oceanographic Information: The NORDA GEOSAT Ocean Applications Program

Abstract

The U.S. Navy's GEOSAT active microwave altimeter provides detailed oceanographic and atmospheric information. It measures global oceanic wind speeds and significant wave height, sea ice edge in the polar regions, and dynamic topography related to mesoscale ocean circulation. The Naval Ocean Research and Development Activity processed near-real-time GEOSAT data to monitor oceanic processes from July 1985 to January 1989. We found that the combination of topographic information from GEOSAT, synoptic sea-surface-temperature information from infrared imagery, and local information from bathythermographs provides valuable information on Gulf Stream circulation. The size of the area involved, the intensity of currents, and the rapidity with which changes occur previously limited our technical ability to observe the Gulf Stream and its attendant spin-off eddies. Long-term study with the information sources described above has given a more complete picture of the Gulf Stream region's mesoscale circulation than ever before achieved.