Abstract
The jet structure of the Southern Ocean front south of Australia is studied in stream-coordinate with a new altimeter product—Absolute Dynamic Topography (ADT) from AVISO. The accuracy of the ADT data is validated with the mooring data from a two-year subantarctic-front experiment. It is demonstrated that the ADT is consistent with in-situ measurements and captures the meso-scale activity of the Antarctic Circumpolar Current (ACC). Stream-coordinate analysis of ADT surface geostrophic flows finds that ACC jets exhibit large spatio-temporal variability and do not correspond to particular streamfunction values. In the circumpolar scope ACC jets display a transient fragmented pattern controlled by topographic features. The poleward shift of jet in streamfunction space, as revealed by a streamwise correlation method, indicates the presence of meridional fluxes of zonal momentum. Such cross-stream eddy fluxes concentrate the broad ACC baroclinic flow into narrow jets. Combined with a recent discovery of gravest empirical mode (GEM) in the thermohaline fields, the study clarifies the interrelationship among front, jet and streamfunction in the Southern Ocean.
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Supported by the National Basic Research Program of China (973 Program) (Nos. 2006CB403601, 2007CB411804), the Knowledge Innovation Program of Chinese Academy of Sciences (No. KZCX2-YW-Q11-02), and the National Natural Sciences Foundation of China (No. 40776014)
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Sun, C., Zhang, L. & Yan, X. Stream-coordinate structure of oceanic jets based on merged altimeter data. Chin. J. Ocean. Limnol. 29, 1–9 (2011). https://doi.org/10.1007/s00343-011-9938-4
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DOI: https://doi.org/10.1007/s00343-011-9938-4