Properties of the Subantarctic Front and Polar Front from the skewness of sea level anomaly

TitleProperties of the Subantarctic Front and Polar Front from the skewness of sea level anomaly
Publication TypeJournal Article
Year of Publication2015
AuthorsShao A.E, Gille ST, Mecking S., Thompson L.
JournalJournal of Geophysical Research-Oceans
Date Published2015/07
Type of ArticleArticle
ISBN Number2169-9275
Accession NumberWOS:000359776000031
Keywordscircumpolar current fronts; hemisphere; jets; performance; satellite altimetry; southern-ocean fronts; surface height; topography; variability

The region of the Southern Ocean that encompasses the Subantarctic Front (SAF) to the north and the Polar Front (PF) to the south contains most of the transport of the Antarctic Circumpolar Current. Here skewness of sea level anomaly (SLA) from 1992 to 2013 is coupled with a meandering Gaussian jetw model to estimate the mean position, meridional width, and the percent variance that each front contributes to total SLA variability. The SAF and PF have comparable widths (85 km) in the circumpolar average, but their widths differ significantly in the East Pacific Basin (85 and 60 km, respectively). Interannual variability in the positions of the SAF and PF are also estimated using annual subsets of the SLA data from 1993 to 2012. The PF position has enhanced variability near strong topographic features such as the Kerguelen Plateau, the Campbell Plateau east of New Zealand, and downstream of Drake Passage. Neither the SAF nor the PF showed a robust meridional trend over the 20 year period. The Southern Annular Mode was significantly correlated with basin-averaged SAF and PF positions in the East Pacific and with the PF south of Australia. A correlation between the PF and the basin-scale wind stress curl anomaly was also found in the western extratropical Pacific but not in other basins.

Short TitleJ Geophys Res-Oceans
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