Fine-jet structure of the Antarctic Circumpolar Current south of Africa

Abstract

The fine structure of the Antarctic Circumpolar Current (ACC) jets south of Africa is investigated by means of the statistical analysis of weekly satellite altimetry data provided by the French CLS agency (DT-Global-MADT-Upd product, http://aviso.oceanobs.com) and the data of the SR02 hydro-physical section executed onboard the R/V Akademik Ioffe in December 2009. Twelve jets of the ACC were revealed in this region. Six jets of the Subantarctic Current, four jets of the South Polar Current, and two jets of the South Antarctic Current are among them. In addition, a jet of the Weddell Current was also revealed. The range of the absolute dynamic topography (ADT) heights corresponding to each jet was about 10–15 cm. It is shown that the jet axes maintain approximately the same ADT values during time intervals of up to half a year, including the dates of the SR02 section. Good agreement was observed between the locations of the jet axes along the section revealed earlier by the authors from direct hydrophysical measurements and the data in this paper based on the altimetry data.