Surface Ocean Circulation and Variability Determined from Satellite Altimetry

Abstract

Measurements of the elevation of the ocean surface, obtained from radar altimeter data, are emerging as a powerful data set available to oceanographers for enhancing their knowledge of the oceans. Data (from the GEOS-3 and SEASAT satellites) obtained over a period of 3.6 years from April, 1975 to November, 1978, were used to study the spatial distribution of mesoscale sea surface variability in the Tasman Sea. Satellite data generally agreed with existing hydrographic measurements. Patterns of higher sea surface variability (up to 64 cm) were shown to be associated with the East Australian current and eddy areas. The low sea surface variability levels in the mid-Tasman Sea suggest some sort of topographic influence by the western edge of the Lord Howe Rise. No evidence for a permanent surface circulation front across the Tasman Sea was found. Altimetric eddy kinetic energy values calculated in the region are of the same order as those obtained from cruise results.