Variability of Circumpolar Deep Water transport onto the Amundsen Sea Continental shelf through a shelf break trough

Journal of Geophysical Research: Oceans - Tập 118 Số 12 - Trang 6603-6620 - 2013
Karen M. Assmann1, Adrian Jenkins1, Deborah R. Shoosmith1, Dziga P. Walker1, Stanley S. Jacobs2, Keith W. Nicholls1
1British Antarctic Survey, Cambridge, UK
2Lamont-Doherty Earth Observatory, Columbia University, Palisades, New York, USA

Tóm tắt

The presence of warm Circumpolar Deep Water (CDW) intrusions on the Amundsen continental shelf has been linked to recent thinning of the outlet glaciers draining the West Antarctic ice sheet into the Amundsen Sea. Inflow of the CDW onto the shelf is thought to occur within a series of troughs that intersect the continental shelf break. We use observations between 1994 and 2011 and a numerical model to investigate the variability of CDW transport in a trough intersecting the shelf break at 113°W. The location of the main CDW inflow into the trough varies between its eastern flank and center, while the western part of the trough is filled by a recirculation that commonly entrains cooler water originating further south on the shelf. Thermocline depth decreases between the early and late 2000s with an indication that the depth of the 1994 thermocline was similar to the later years. Mooring results show that the CDW layer cools and thins in summer and thickens and warms in winter. In addition to a deeper thermocline in summer, we observe a stronger presence of Lower CDW in the bottom of the trough. Heat flux onto the shelf is controlled by current velocities rather than CDW temperature and the majority of the heat is carried onto the shelf by background flow rather than episodic events.

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Tài liệu tham khảo

10.1175/1520-0426(1995)012<0567:SATCIT>2.0.CO;2

Antonov J. I., 2010, NOAA Atlas NESDIS 69, 184

10.1038/NGEO1644

10.1007/s10236‐004‐0106‐7

10.1038/ngeo362

10.1175/2008JCLI2131.1

10.1007/978-88-470-2250-8_6

10.1029/AR075p0083

10.5670/oceanog.2012.90

10.1002/JGRC.20298

10.1029/96GL00723

10.1126/science.1069574

10.1038/ngeo1188

10.1038/NGEO890

10.1175/2008JPO3753.1

10.1029/95JC02901

10.1029/94RG01872

Locarnini R. A., 2010, NOAA Atlas NESDIS 68, 184

10.1029/2007JC004368

10.1016/j.ocemod.2009.12.008

10.5194/os‐8–433‐2012

10.1175/1520-0485(1999)029<1723:WFDSCA>2.0.CO;2

10.1029/2008JC004955

10.1016/j.dsr.2013.04.001

10.1029/2007RG000250

10.1029/2007GC001694

10.1016/0967-0637(95)00021-W

10.3189/172756402781817752

10.1017/S0954102003001032

10.1016/S0098-3004(02)00013-4

10.1038/nature08471

10.1126/science.1070942

10.1038/ngeo102

10.1126/science.1235798

10.1175/2010BAMS3001.1

10.3189/2012AoG6‐A073

10.1126/science.291.5505.862

10.1175/JPO‐D‐11–0237.1

10.3189/2012AoG60A110

10.1029/2008GL034939

10.5194/essd‐2–261‐2010

10.1016/0167-2789(92)90103-T

10.1175/2010JPO4431.1

10.1175/JPO‐D‐12–0157.1

10.1029/2006GL028154

10.1002/JGRC.20212

10.1029/AR075p0001

10.1029/2009GL039126

10.3189/172756505781829007

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Journal of Geophysical Research: Oceans

Tập 118 Số 12

6603-6620

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