Use of Japanese satellite GMS for following the East Australian Current

Abstract

A series of infrared images from the Japanese geostationary meteorological satellite (GMS) for the period late July to early December 1980 was found to reveal many useful oceanographic features of the western Tasman Sea. Although the temperature signal is digitized in steps of 1.73º C, the disadvantage of this somewhat coarse thermal resolution was offset to some extent by the availability of frequent images. The positions of eddy centres could be estimated within ±0.25 of an eddy diameter from September onwards, and it was possible to follow their movements over time scales of the order of a month. The hot surface 'core' of the East Australian Current off northern New South Wales was discernible intermittently on images, and composites of core positions over a month revealed complex time variations in current axes. Cloud cover is a major limitation for infrared imagery, but some oceanographic feature was discernible on 63% of images.