The Antarctic Circumpolar Current between the Falkland Islands and South Georgia
Hydrographic and lowered acoustic Doppler current profiler data along a line from the Falkland Islands to South Georgia via the Maurice Ewing Bank are used to estimate the flow of circumpolar water into the Argentine Basin, and to study the interaction of the Antarctic Circumpolar Current with the F...
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ftoceandocs:oai:aquadocs.org:1834/17160 2024-06-09T07:40:36+00:00 The Antarctic Circumpolar Current between the Falkland Islands and South Georgia Arhan, M. Naveira Garabato, A. Heywood, K. Stevens, D. 2002 pp.1914-1931 http://hdl.handle.net/1834/17160 https://doi.org/10.1175/1520-0485(2002)032<1914:TACCBT>2.0.CO;2 en eng https://doi.org/10.1175/1520-0485(2002)032<1914:TACCBT>2.0.CO;2 http://hdl.handle.net/1834/17160 Journal Contribution Refereed 2002 ftoceandocs https://doi.org/10.1175/1520-0485(2002)032<1914:TACCBT>2.0.CO;2 2024-05-15T08:02:16Z Hydrographic and lowered acoustic Doppler current profiler data along a line from the Falkland Islands to South Georgia via the Maurice Ewing Bank are used to estimate the flow of circumpolar water into the Argentine Basin, and to study the interaction of the Antarctic Circumpolar Current with the Falkland Plateau. The estimated net transport of 129 21 Sv (Sv 106 m3 s1 ) across the section is shared between three major current bands. One is associated with the Subantarctic Front (SAF; 52 6 Sv), and the other two with branches of the Polar Front (PF) over the sill of the Falkland Plateau (44 9 Sv) and in the northwestern Georgia Basin (45 9 Sv). The latter includes a local reinforcement (20 Sv) by a deep anticyclonic recirculation around the Maurice Ewing Bank. While the classical hydrographic signature of the PF stands out in this eastbound branch, it is less distinguishable in the northbound branch over the plateau. Other circulation features are a southward entrainment of diluted North Atlantic Deep Water from the Argentine Basin over the eastern part of the Falkland Plateau, and an abyssal anticyclonic flow in the western Georgia Basin, opposite to what was generally assumed. The different behavior of the SAF and PF at the Falkland Plateau (no structural modification of the former and partitioning of the latter) is attributed to the PF being deeper than the sill depth on the upstream side of the plateau, unlike the SAF. It is suggested that the partitioning takes place at a location where the 2500-m and 3000-m isobaths diverge at the southern edge of the plateau. The western branch of the PF crosses the plateau at a distance of 250 km to the east of the SAF. Comparison with a section across the Falkland Current farther downstream shows that its deep part subsequently joins the SAF on the northern side of the plateau where the 2000–3000 m isobaths converge in the steep Falkland Escarpment. The result of this two-stage bathymetric effect is a net transfer of at least 10 Sv from the PF to the SAF at ... Book Antarc* Antarctic North Atlantic Deep Water North Atlantic IODE-UNESCO: OceanDocs - E-Repository of Ocean Publications Antarctic Argentine Ewing ENVELOPE(-61.257,-61.257,-69.924,-69.924) Falkland Escarpment ENVELOPE(-45.000,-45.000,-50.000,-50.000) Falkland Plateau ENVELOPE(-50.000,-50.000,-51.000,-51.000) Georgia Basin ENVELOPE(-35.500,-35.500,-50.750,-50.750) Maurice ENVELOPE(-55.817,-55.817,-63.133,-63.133) Maurice Ewing Bank ENVELOPE(-43.500,-43.500,-50.667,-50.667) The Antarctic |
institution |
Open Polar |
collection |
IODE-UNESCO: OceanDocs - E-Repository of Ocean Publications |
op_collection_id |
ftoceandocs |
language |
English |
description |
Hydrographic and lowered acoustic Doppler current profiler data along a line from the Falkland Islands to South Georgia via the Maurice Ewing Bank are used to estimate the flow of circumpolar water into the Argentine Basin, and to study the interaction of the Antarctic Circumpolar Current with the Falkland Plateau. The estimated net transport of 129 21 Sv (Sv 106 m3 s1 ) across the section is shared between three major current bands. One is associated with the Subantarctic Front (SAF; 52 6 Sv), and the other two with branches of the Polar Front (PF) over the sill of the Falkland Plateau (44 9 Sv) and in the northwestern Georgia Basin (45 9 Sv). The latter includes a local reinforcement (20 Sv) by a deep anticyclonic recirculation around the Maurice Ewing Bank. While the classical hydrographic signature of the PF stands out in this eastbound branch, it is less distinguishable in the northbound branch over the plateau. Other circulation features are a southward entrainment of diluted North Atlantic Deep Water from the Argentine Basin over the eastern part of the Falkland Plateau, and an abyssal anticyclonic flow in the western Georgia Basin, opposite to what was generally assumed. The different behavior of the SAF and PF at the Falkland Plateau (no structural modification of the former and partitioning of the latter) is attributed to the PF being deeper than the sill depth on the upstream side of the plateau, unlike the SAF. It is suggested that the partitioning takes place at a location where the 2500-m and 3000-m isobaths diverge at the southern edge of the plateau. The western branch of the PF crosses the plateau at a distance of 250 km to the east of the SAF. Comparison with a section across the Falkland Current farther downstream shows that its deep part subsequently joins the SAF on the northern side of the plateau where the 2000–3000 m isobaths converge in the steep Falkland Escarpment. The result of this two-stage bathymetric effect is a net transfer of at least 10 Sv from the PF to the SAF at ... |
format |
Book |
author |
Arhan, M. Naveira Garabato, A. Heywood, K. Stevens, D. |
spellingShingle |
Arhan, M. Naveira Garabato, A. Heywood, K. Stevens, D. The Antarctic Circumpolar Current between the Falkland Islands and South Georgia |
author_facet |
Arhan, M. Naveira Garabato, A. Heywood, K. Stevens, D. |
author_sort |
Arhan, M. |
title |
The Antarctic Circumpolar Current between the Falkland Islands and South Georgia |
title_short |
The Antarctic Circumpolar Current between the Falkland Islands and South Georgia |
title_full |
The Antarctic Circumpolar Current between the Falkland Islands and South Georgia |
title_fullStr |
The Antarctic Circumpolar Current between the Falkland Islands and South Georgia |
title_full_unstemmed |
The Antarctic Circumpolar Current between the Falkland Islands and South Georgia |
title_sort |
antarctic circumpolar current between the falkland islands and south georgia |
publishDate |
2002 |
url |
http://hdl.handle.net/1834/17160 https://doi.org/10.1175/1520-0485(2002)032<1914:TACCBT>2.0.CO;2 |
long_lat |
ENVELOPE(-61.257,-61.257,-69.924,-69.924) ENVELOPE(-45.000,-45.000,-50.000,-50.000) ENVELOPE(-50.000,-50.000,-51.000,-51.000) ENVELOPE(-35.500,-35.500,-50.750,-50.750) ENVELOPE(-55.817,-55.817,-63.133,-63.133) ENVELOPE(-43.500,-43.500,-50.667,-50.667) |
geographic |
Antarctic Argentine Ewing Falkland Escarpment Falkland Plateau Georgia Basin Maurice Maurice Ewing Bank The Antarctic |
geographic_facet |
Antarctic Argentine Ewing Falkland Escarpment Falkland Plateau Georgia Basin Maurice Maurice Ewing Bank The Antarctic |
genre |
Antarc* Antarctic North Atlantic Deep Water North Atlantic |
genre_facet |
Antarc* Antarctic North Atlantic Deep Water North Atlantic |
op_relation |
https://doi.org/10.1175/1520-0485(2002)032<1914:TACCBT>2.0.CO;2 http://hdl.handle.net/1834/17160 |
op_doi |
https://doi.org/10.1175/1520-0485(2002)032<1914:TACCBT>2.0.CO;2 |
_version_ |
1801383978477813760 |