Observations of the Dynamics of the Antarctic Circumpolar Current in the Pacific Sector of the Southern Ocean

  • E. Zambianchi
  • G. Budillon
  • P. Falco
  • G. Spezie
Conference paper


This paper describes long term measurements of the Antarctic Circumpolar Current carried out by means of surface and sub-surface drifters deployed as of the austral summer 1993-94, associated with XBT sections. At the surface, the velocity presents a gross zonal flow pattern, directed eastwards. The field is characterized by strong meridional shear and by a complex multiple jet structure, suggested in particular by the observations in the vicinity of the Antarctic-Pacific Ridge. The interaction with the bottom topography is seen to play a major role in shaping both the mean and the eddy fields, with a characteristic space lag which implies the presence of eddy-generating mechanisms in correspondence of major topographic features. Our subsurface float observations denote a strong vertical coupling in the velocity field. Velocities around 1000 m depth resemble those at the surface, with a scale factor of about 1/4 in magnitude. This vertical coherence is consistent with previous hydrographic analyses and with preliminary potential vorticity estimates drawn from our surface drifters data.


Southern Ocean Bottom Topography Antarctic Circumpolar Current Drake Passage Eddy Kinetic Energy 
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.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. 1.
    CLIMA Project Group (1997) Climatic Long-term Interaction for the Mass balance in Antarctica. Int WOCE News 27: 34–35Google Scholar
  2. 2.
    Deacon GER (1937) A general account of the hydrology of the Southern Ocean. Discovery Reps 15: 1–124Google Scholar
  3. 3.
    Deacon GER (1963) The Southern Ocean. In: Hill MN (ed) The sea. Interscience Publishers, New York, vol 2, pp 281–296Google Scholar
  4. 4.
    Nowlin WD Jr, Klinck JM (1986) The physics of the Antarctic Circumpolar Current. Rev Geophys 24: 469–491CrossRefGoogle Scholar
  5. 5.
    Gordon AL (1988) Spatial and temporal variability within the Southern Ocean. In: Sahrhage D (ed) Antarctic Ocean and resources variability. Springer-Verlag, Berlin, pp 43–56Google Scholar
  6. 6.
    Hofmann EE (1985) The large-scale horizontal structure of the Antarctic Circumpolar Current from FGGE drifters. J Geophys Res 90: 7087–7097CrossRefGoogle Scholar
  7. 7.
    Orsi AH, Whitworth T III, Nowlin WD Jr (1995) On the meridional extent and fronts of the Antarctic Circumpolar Current. Deep-Sea Res 42: 641–673CrossRefGoogle Scholar
  8. 8.
    Gordon AL, Molinelli E, Baker T (1978) Large-scale relative dynamic topography of the Southern Ocean. J Geophys Res 83: 3023–3032CrossRefGoogle Scholar
  9. 9.
    Gordon AL, Molinelli E (1982) Southern Ocean Atlas. Columbia University Press, New YorkGoogle Scholar
  10. 10.
    Tomczak M, Godfrey JS (1994) Regional Oceanography. Pergamon Press, OxfordGoogle Scholar
  11. 11.
    Patterson SL, Whitworth T (1990) Physical oceanography. In: Glasby GP (ed) Antarctic sector of the Pacific. Elsevier, Amsterdam, pp 55–93Google Scholar
  12. 12.
    Sciremammano F Jr, Pillsbury RT, Nowlin WD Jr, Whitworth T III (1980) Spatial scales of temperature and flow in Drake Passage J Geophys Res 85: 4015–4028Google Scholar
  13. 13.
    Sybrandy AL, Niiler PP (1991) WOCE/TOGA Lagrangian drifter construction manual. WOCE Rep 63, Scripps Institution of Oceanography, La Jolla, CaliforniaGoogle Scholar
  14. 14.
    Niiler PP, Davis RE, White HJ (1987) Water-following characteristics of a mixed layer drifter. Deep Sea Res 34: 1867–1881CrossRefGoogle Scholar
  15. 15.
    Niiler PP, Sybrandy AL, Bi K, Poulain P-M, Bitterman D (1995) Measurements of the water following capability of holey sock and TRISTAR drifters. Deep Sea Res 42: 1951–1964CrossRefGoogle Scholar
  16. 16.
    Hansen DV, Poulain P-M (1996) Processing of WOCE/TOGA drifter data. J Atmos Oceanic Technol 13: 900–909CrossRefGoogle Scholar
  17. 17.
    Gordon AL (1972) On the interaction of the Antarctic Circumpolar Current and the Macquarie Ridge. Antarctic Res Ser 19: 71–78CrossRefGoogle Scholar
  18. 18.
    Stramma L, Peterson RG, Tomczak M (1995) The South Pacific Current. J Phys Oceanogr 25: 77–91CrossRefGoogle Scholar
  19. 19.
    Piola AR, Figueroa HA, Bianchi AA (1987) Some aspects of the surface circulation south of 20°S revealed by FGGE drifters. J Geophys Res 92: 5101–5115CrossRefGoogle Scholar
  20. 20.
    Deacon GER (1982) Physical and biological zonation in the Southern Ocean. Deep Sea Res 29: 115Google Scholar
  21. 21.
    Olson DB, Podesta G, Evans R, Brown 0 (1988) Temporal variations in the separation of Brazil and Malvinas currents. Deep Sea Res 35: 1971–1990Google Scholar
  22. 22.
    Grezio A (1995) A study of the Antarctic Circumpolar Current by Lagrangian measurements (in Italian). Degree thesis, Istituto Universitario Navale, NapoliGoogle Scholar
  23. 23.
    Spezie G, Zambianchi E (1996) Lagrangian measurements in the Antarctic Circumpolar Current: preliminary results (in Italian). 11 AIOL Congress Proc 701–711Google Scholar
  24. 24.
    Bauer S, Swenson MS, Griffa A, Mariano A, Owens K (1997) Eddy-mean flow decomposition and eddy-diffusivity estimates in the tropical Pacific Ocean. J Geophys Res (in press)Google Scholar
  25. 25.
    Patterson SL (1985) Surface circulation and kinetic energy distribution in the Southern hemisphere oceans from FGGE buoys. J Phys Oceanogr 15: 865–884CrossRefGoogle Scholar
  26. 26.
    Morrow R, Coleman R, Church J, Chelton D (1994) Surface eddy momentum flux and velocity variances in the Southern Ocean from GEOSAT altimetry. J Phys Oceanogr 24: 2050–2061CrossRefGoogle Scholar
  27. 27.
    Lutjeharms JRE, Baker DJ Jr (1980) A statistical analysis of the meso-scale dynamics of the Southern Ocean. Deep Sea Res 27: 145–159CrossRefGoogle Scholar
  28. 28.
    Zambianchi E, Spezie G (1997) Lagrangian observations of shear and vorticity in the Antarctic Circumpolar Current. In preparationGoogle Scholar
  29. 29.
    Davis RE, Webb DC, Regier LA, Dufour J (1992) The Autonomous LAgrangian Circulation Explorer ( ALACE ). J Atmos Oceanic Technol 9: 264–285Google Scholar
  30. 30.
    Davis RE, Killworth PD, Blundell JR (1996) Comparison of Autonomous LAgrangian Circulation Explorer and Fine Resolution Antarctic Model results in the South Atlantic. J Geophys Res 101: 855–884CrossRefGoogle Scholar
  31. 31.
    Nowlin WD Jr, Whitworth T III, Pillsbury RT (1977) Structure and transport of the Antarctic Circumpolar Current at Drake Passage from short-term measurements. J Phys Oceanogr 7: 788–802CrossRefGoogle Scholar
  32. 32.
    Treshnikov AF, Pillsbury RT, Nowlin WD Jr, Sarukhanian EI, Smirnov NP (1977) A comparison of summer current measurements in the Drake Passage. J Phys Oceanogr 7: 610–614CrossRefGoogle Scholar
  33. 33.
    Wessel P, Smith WHF (1991). Free software helps map and display data. EOS Trans AGU 72: 441CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Italia, Milano 1999

Authors and Affiliations

  • E. Zambianchi
    • 1
  • G. Budillon
    • 1
  • P. Falco
    • 1
  • G. Spezie
    • 1
  1. 1.Istituto di Meteorologia e OceanografiaIstituto Universitario NavaleNapoliItaly

Personalised recommendations