Outflow of Weddell sea waters into the Scotia Sea through the western sector of the South Scotia Ridge

• Main Author: Palmer García, Margarita
• Other Authors: Gomis Bosch, Damià, Universitat de les Illes Balears. Departament de Física
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: Universitat de les Illes Balears 2013
• Subjects: 53; Antarctic; Hesperides Trough; Sassi; Scotia Sea; South Orkney Islands; South Scotia Ridge; South Shetland Islands; The Antarctic; Weddell; Weddell Sea; Antarc*; International Polar Year
• Online Access: http://hdl.handle.net/10803/107969

This work compiles the results of the analysis of hydrographical data collected in January 2008 over the western sector of the South Scotia Ridge (SSR). The cruise was carried out on board R/V Hespérides in the framework of the Synoptic Antarctic Shelf-Slope Interaction (SASSI) study, one of the core projects endorsed by the International Polar Year. SASSI focused on shelf-slope processes taking place all along the Antarctic continental slope, paying particular attention to the Antarctic Slope Front (ASF) and its associated westward Antarctic Slope Current (ASC). The Spanish contribution to SASSI (framed by the E-SASSI project) focused on the SSR region between the South Shetland Islands and the South Orkney Islands, bounded to the north by the Scotia Sea and to the south by the Weddell Sea. The main objectives of E-SASSI were (1) to quantify the outflow of Weddell Sea waters into the Scotia Sea and to determine how these waters contribute to the modification of the Southern Boundary (SB) of the Antarctic Circumpolar Current (ACC); (2) to determine the role of the Antarctic Slope Front in these processes; and (3) to track the path of the Antarctic Slope Current before diluting into the Scotia Sea. This thesis aims to answer these questions. The sector of the SSR located between the South Shetland Islands and the South Orkney Islands is a region of especial interest. First because the gaps indenting the ridge constitute the first gate for the outflow of relatively shallow, recently ventilated waters from the northwestern Weddell Sea into the Scotia Sea. Second, because of the complexity of the bathymetry: a deep trough (the Hesperides Trough) separates the northern and southern flanks of the ridge and the location and depth of the different gaps indenting the ridge constrain the pathway of the Antarctic Slope Current. A key feature of the E-SASSI cruise with respect to previous studies conducted in the region is the unprecedented high spatial resolution of the hydrographic survey, particularly over the ...