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The Large-Scale Thermohaline Structure of the Ross Gyre

  • V. Gouretski

Abstract

This study describes the large-scale thermohaline structure and circulation patterns of the Ross Gyre and is based on a quality controlled data set including about 7,000 historical and modern hydrographic stations. A new regional climatology was obtained through the objective analysys of the data on neutral surfaces. Steric height anomaly maps portray Ross Gyre as a depression south of the mid-ocean ridge between about 170°E and 140°W. The centre of the gyre shifts with depth from about 68°S 164°W in near surface levels to about 63oS 150oW at 1500 meters. Maximum estimate of the geostrophic transport within the gyre is 8.5 Sv near 150°W, a factor of three lower than corresponding estimates for the Weddell Gyre. Data from a quasi-synoptic survey made by three former U.S.S.R vessels in 1985-86 are used for a more detailed description of the gyre’s northern, eastern and southern boundaries. Similar to the Weddell Gyre the location of the eastern boundary is controlled by the southward extension of the Antarctic Circumpolar Current core flowing through the Udintsev Fracture Zone with the geostrophic transport of 56 Sv. The Circumpolar Deep Water spreads westwards along the southern limb of the gyre with potential temperatures still as high as 1.6°C at 75°S, 150°W.

Keywords

Antarctic Circumpolar Current Antarctic Bottom Water Antarctic Polar Front Southern Limb Circumpolar Deep Water 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Italia, Milano 1999

Authors and Affiliations

  • V. Gouretski
    • 1
  1. 1.WHP Special Analysis Centre (jointly operated by Max-Planck-Institut für Meteorologie und Bundesamt für Seeschiffahrt und Hydrographie)HamburgGermany

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