The Antarctic Slope Current near 30 degree E

• Published in: Journal of geophysical research. Oceans 2016-02, Vol.121 (2), p.1051-1062
• Main Authors: Dong, Jun, Speer, Kevin, Jullion, Loic
• Format: Article
• Language: English
• Subjects: Antarctica; Banks; Coastal; Geophysics; Gyres; Marine; Sea currents; Slopes; Transport
• ISSN: 2169-9275; 2169-9291
• DOI: 10.1002/2015JC011099

The Antarctic Slope Current flows westward above the continental slope of Antarctica, entering the Weddell Sea near 30 degree E and supplying dense water to the deep overturning cell there, and contributing to global Antarctic Bottom Water formation. Observations from the 2008 I6S hydrographic section are used to investigate the strength of the Slope Current near 30 degree E. A prominent topographic feature, the Gunnerus Bank, diverts the Slope Current upstream of this longitude, and has a large effect on the current's structure, splitting it into a coastal and offshore component. The bank also enhances water mass mixing and lateral exchange across the slope. As part of the 2008 occupation, an additional line was made along the crest of the bank, forming a closed volume over the western side. By combining hydrographic and Lowered Acoustic Doppler Current Profiler measurements in this box using an inverse method, the Slope Current transport is estimated to be 9.6 plus or minus 2.3 Sv; the transport associated with the Antarctic Slope Front is 4.0 plus or minus 0.3 Sv, of which 1.8 plus or minus 0.3 Sv enters the Weddell Gyre as recently formed dense water. Key Points: * Antarctic Slope Current transport near 30 E is estimated to be 9.6 plus or minus 2.3 Sv * The Antarctic Slope Front transport is 4.0 plus or minus 0.3 Sv * 1.8 plus or minus 0.03 Sv enters the Weddell Gyre as recently formed dense water