Circulation and transport of water masses in the Lazarev Sea, Antarctica, during summer and winter 2006

Cisewski, Boris, Strass, Volker H and Leach, Harry ORCID: 0000-0003-1774-5167 (2011) Circulation and transport of water masses in the Lazarev Sea, Antarctica, during summer and winter 2006. Deep Sea Research Part I: Oceanographic Research Papers, 58 (2). pp. 186-199.

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Abstract

The distribution and circulation of water masses in the region between 6°W and 3°E and between the Antarctic continental shelf and 60°S are analyzed using hydrographic and shipboard acoustic Doppler current profiler (ADCP) data taken during austral summer 2005/2006 and austral winter 2006. In both seasons two gateways are apparent where Warm Deep Water (WDW) and other water masses enter the Weddell Gyre through the Lazarev Sea: (a) a probably topographically trapped westward, then southwestward circulation around the northwestern edge of Maud Rise with maximum velocities of about 20cms-1 and (b) the Antarctic Coastal Current (AntCC), which is confined to the Antarctic continental shelf slope and is associated with maximum velocities of about 25cms-1.Along two meridional sections that run close to the top of Maud Rise along 3°E, geostrophic velocity shears were calculated from CTD measurements and referenced to velocity profiles recorded by an ADCP in the upper 300m. The mean accuracy of the absolute geostrophic velocity is estimated at ±2cms-1. The net baroclinic transport across the 3°E section amounts to 20 and 17Sv westward for the summer and winter season, respectively. The majority of the baroclinic transport, which accounts for ~60% of the total baroclinic transport during both surveys, occurs north of Maud Rise between 65° and 60°S.However, the comparison between geostrophic estimates and direct velocity measurements shows that the circulation within the study area has a strong barotropic component, so that calculations based on the dynamic method underestimate the transport considerably. Estimation of the net absolute volume transports across 3°E suggests a westward flow of 23.9±19.9. Sv in austral summer and 93.6±20.1. Sv in austral winter. Part of this large seasonal transport variation can be explained by differences in the gyre-scale forcing through wind stress curl. © 2010 Elsevier Ltd.

Item Type:	Article
Additional Information:	## TULIP Type: Articles/Papers (Journal) ##
Uncontrolled Keywords:	14 Life Below Water
Divisions:	Faculty of Science and Engineering > School of Environmental Sciences
Depositing User:	Symplectic Admin
Date Deposited:	19 Mar 2024 16:34
Last Modified:	19 Mar 2024 16:34
DOI:	10.1016/j.dsr.2010.12.001
Related URLs:	Publisher
URI:	https://livrepository.liverpool.ac.uk/id/eprint/3179638