An anticyclonic circulation above the Northwest Georgia Rise, Southern Ocean

• Published in: Geophysical research letters Vol. 30; no. 20; pp. 2061 - n/a
• Main Authors: Meredith, Michael P., Watkins, Jon L., Murphy, Eugene J., Cunningham, Nathan J., Wood, Andrew G., Korb, Rebecca, Whitehouse, Mick J., Thorpe, Sally E., Vivier, Frédéric
• Format: Journal Article
• Language: English
• Published: American Geophysical Union 01.10.2003; Blackwell Publishing Ltd
• Subjects: Arctic and Antarctic oceanography; Currents; Fronts and jets; General circulation; Hydrography; Marine; Oceanography; Physical; PSW, South Atlantic, Georgia Rise; ASW, USA, Georgia; PSW, South Atlantic, South Georgia
• ISSN: 0094-8276; 1944-8007
• DOI: 10.1029/2003GL018039

Data from a variety of sources reveal a warm‐core anticyclonic circulation above the Northwest Georgia Rise (NWGR), an ∼2000‐m high bathymetric feature north of South Georgia. The sense of the circulation is opposite to the general cyclonic flow in the Georgia Basin. The circulation shows the characteristics of a stratified Taylor column: dimensional analysis shows that the local bathymetry and hydrography are conducive to the formation of such. ERS2 altimeter data show that the column, whilst not fully permanent, is nonetheless a recurring feature. High concentrations of chlorophyll‐a are observed at the centre of the circulation, indicating that the modulation of the physical environment has significant consequences for the local biogeochemical system via enhanced primary production. Enhanced chlorophyll‐a extends in a long plume from the NWGR along pathways indicated by drifters; this passive redistribution may have consequences for the larger (basin‐) scale ecosystem.