Abstract
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.
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© 1999 Springer-Verlag Italia, Milano
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Zambianchi, E., Budillon, G., Falco, P., Spezie, G. (1999). Observations of the Dynamics of the Antarctic Circumpolar Current in the Pacific Sector of the Southern Ocean. In: Spezie, G., Manzella, G.M.R. (eds) Oceanography of the Ross Sea Antarctica . Springer, Milano. https://doi.org/10.1007/978-88-470-2250-8_3
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DOI: https://doi.org/10.1007/978-88-470-2250-8_3
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