A Cyclonic Eddy in the Antarctic Circumpolar Current South of Australia: Results of Soviet-American Observations Aboard the R/VProfessor Zubov

Direct velocity measurements in the Subantarctic Front and over Campbell Plateau, southeast of New Zealand

“…Similar eddies have been observed elsewhere in the SAF. Savchenko et al [1978] identified a strong cyclonic eddy south of the SAF at longitude 132°E, south of Australia. Peterson et al [1982] described the generation and evolution of a cyclonic ring in Drake Passage.…”

Dynamics of the Antarctic circumpolar current : evidence for topographic effects from altimeter data and numerical model output

“…the baroclinic transport is relatively stable, while the barotropic transport fluctuates on the order of 50 x 106 m 3 s -1, with a standard deviation of 10 x 106 m 3 s -1 . In a few cases, wave growth and ring formation events have been observed in roughly synoptic expendable bathythermography (XBT) and hydrographic surveys at Drake Passage [Joyce and Patterson, 1977;Peterson et al, 1982] and south of Australia [Savchenko et al, 1978], but little information has been available to investigate variability throughout the Southern Ocean. One tool which has proved useful for synoptic studies of mesoscale structures in the Gulf Stream and the Kuroshio, advanced very high resolution radiometer (AVHRR) sea surface temperature data, is of extremely limited use in the Southern Ocean because of the nearly constant cloud cover in the region.…”

Baroclinic multipole evolution in shear and strain

“…In the oceans, the Mediterranean Water eddies southwest of the Iberian Peninsula (Carton 2001), the Southern Bay slope water oceanic eddies (Pingree and Le Cann 1992) or the Gulf Stream warm-core rings (Kennelly et al 1985) can form baroclinic multipoles which are also subject to shear and strain induced by neighboring currents and eddies. Although hetons have been observed in the Antarctic Circumpolar Current (Savchenko et al 1978), a generalization of this study to a baroclinic external flow should be carried out. But the stability of meddies or of Gulf Stream rings is due to their nonlinearity and to their finite size.…”

“…contraction occurs along y ¼ x) and cyclonic rotation around the origin of the (x, y) plane; if they are negative, all directions are reversed. An external flow of form (1) has a critical point (0; 0) of elliptic type when jj4jSj and of hyperbolic type when jj jSj.y For oceanic application, a nearly barotropic shear can correspond to the Antarctic circumpolar current in which hetons have been observed (Savchenko et al 1978).…”