Transport of warm Upper Circumpolar Deep Water onto the western Antarctic Peninsula continental shelf 1Division of Ocean and Climate Physics, Lamont-Doherty Earth Observatory of Columbia University, 61 Route 9W, Palisades, NY 10964, USA
10 Jul 2012
2Department of Earth and Environmental Sciences, Columbia University, New York, NY USA
Received: 31 October 2011 – Published in Ocean Sci. Discuss.: 15 December 2011 Abstract. Five thermistor moorings were placed on the continental shelf of the western
Antarctic Peninsula (between 2007 and 2010) in an effort to identify the
mechanism(s) responsible for delivering warm Upper Circumpolar Deep Water
(UCDW) onto the broad continental shelf from the Antarctic Circumpolar
Current (ACC) flowing over the adjacent continental slope. Historically,
four mechanisms have been suggested: (1) eddies shed from the ACC, (2) flow
into the cross-shelf-cutting canyons with overflow onto the nominal shelf,
(3) general upwelling, and (4) episodic advective diversions of the ACC onto
the shelf. The mooring array showed that for the years of deployment, the
dominant mechanism is eddies; upwelling may also contribute but to an
unknown extent. Mechanism 2 played no role, though the canyons have been
shown previously to channel UCDW across the shelf into Marguerite Bay.
Mechanism 4 played no role independently, though eddies may be advected
within a greater intrusion of the background flow.
Revised: 14 April 2012 – Accepted: 02 May 2012 – Published: 10 July 2012
Citation: Martinson, D. G. and McKee, D. C.: Transport of warm Upper Circumpolar Deep Water onto the western Antarctic Peninsula continental shelf, Ocean Sci., 8, 433-442, doi:10.5194/os-8-433-2012, 2012.