Physical and biological coupling in eddies in the lee of the South-West Indian Ridge
Eddies have some decisive functions in the dynamics of the Southern Ocean ecosystems. This is particularly true in the Indian sector of the Southern Ocean, where a region of unusually high-mesoscale variability has been observed in the vicinity of the South-West Indian Ridge. In April 2003, three ed...
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ftsealsdc:vital:6493 2023-05-15T13:39:22+02:00 Physical and biological coupling in eddies in the lee of the South-West Indian Ridge Ansorge, Isabelle J Pakhomov, E A Kaehler, Sven Lutjeharms, Johan R E Durgadoo, J V 2010 17 pages pdf http://vital.seals.ac.za:8080/vital/access/manager/Repository/vital:6493 http://hdl.handle.net/10962/d1004477 English eng vital:6493 http://vital.seals.ac.za:8080/vital/access/manager/Repository/vital:6493 http://hdl.handle.net/10962/d1004477 Article 2010 ftsealsdc 2021-09-02T23:10:08Z Eddies have some decisive functions in the dynamics of the Southern Ocean ecosystems. This is particularly true in the Indian sector of the Southern Ocean, where a region of unusually high-mesoscale variability has been observed in the vicinity of the South-West Indian Ridge. In April 2003, three eddies were studied: eddy A, a recently spawned anticyclone south of the Antarctic Polar Front (APF),; eddy B, an anticyclone north of lying between the Subantarctic Front and the APF; and eddy C, a cyclone north of the APF west of the ridge. Elevated concentrations of total Chl-a coincided with the edges of the cyclonic eddy, whereas both anticyclonic eddies A and B were characterised by low total Chl-a concentrations. Biologically, the two anticyclonic eddies A and B were distinctly different in their biogeographic origin. The zooplankton community in the larger anticyclonic eddy A was similar in composition to the Antarctic Polar Frontal Zone (APFZ) community with an addition of some Antarctic species suggesting an origin just north of the APF. In contrast, the species composition within the second anticyclonic eddy B appeared to be more typical of the transitional nature of the APFZ, comprising species of both subantarctic and subtropical origin and thus influenced by intrusions of water masses from both north and south of the Subantarctic Front. Back-tracking of these features shows that the biological composition clearly demarcates the hydrographic origin of these features. Article in Journal/Newspaper Antarc* Antarctic Southern Ocean SEALS Digital Commons (South East Academic Libraries System, South Africa) Antarctic Southern Ocean The Antarctic Indian |
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SEALS Digital Commons (South East Academic Libraries System, South Africa) |
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ftsealsdc |
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English |
description |
Eddies have some decisive functions in the dynamics of the Southern Ocean ecosystems. This is particularly true in the Indian sector of the Southern Ocean, where a region of unusually high-mesoscale variability has been observed in the vicinity of the South-West Indian Ridge. In April 2003, three eddies were studied: eddy A, a recently spawned anticyclone south of the Antarctic Polar Front (APF),; eddy B, an anticyclone north of lying between the Subantarctic Front and the APF; and eddy C, a cyclone north of the APF west of the ridge. Elevated concentrations of total Chl-a coincided with the edges of the cyclonic eddy, whereas both anticyclonic eddies A and B were characterised by low total Chl-a concentrations. Biologically, the two anticyclonic eddies A and B were distinctly different in their biogeographic origin. The zooplankton community in the larger anticyclonic eddy A was similar in composition to the Antarctic Polar Frontal Zone (APFZ) community with an addition of some Antarctic species suggesting an origin just north of the APF. In contrast, the species composition within the second anticyclonic eddy B appeared to be more typical of the transitional nature of the APFZ, comprising species of both subantarctic and subtropical origin and thus influenced by intrusions of water masses from both north and south of the Subantarctic Front. Back-tracking of these features shows that the biological composition clearly demarcates the hydrographic origin of these features. |
format |
Article in Journal/Newspaper |
author |
Ansorge, Isabelle J Pakhomov, E A Kaehler, Sven Lutjeharms, Johan R E Durgadoo, J V |
spellingShingle |
Ansorge, Isabelle J Pakhomov, E A Kaehler, Sven Lutjeharms, Johan R E Durgadoo, J V Physical and biological coupling in eddies in the lee of the South-West Indian Ridge |
author_facet |
Ansorge, Isabelle J Pakhomov, E A Kaehler, Sven Lutjeharms, Johan R E Durgadoo, J V |
author_sort |
Ansorge, Isabelle J |
title |
Physical and biological coupling in eddies in the lee of the South-West Indian Ridge |
title_short |
Physical and biological coupling in eddies in the lee of the South-West Indian Ridge |
title_full |
Physical and biological coupling in eddies in the lee of the South-West Indian Ridge |
title_fullStr |
Physical and biological coupling in eddies in the lee of the South-West Indian Ridge |
title_full_unstemmed |
Physical and biological coupling in eddies in the lee of the South-West Indian Ridge |
title_sort |
physical and biological coupling in eddies in the lee of the south-west indian ridge |
publishDate |
2010 |
url |
http://vital.seals.ac.za:8080/vital/access/manager/Repository/vital:6493 http://hdl.handle.net/10962/d1004477 |
geographic |
Antarctic Southern Ocean The Antarctic Indian |
geographic_facet |
Antarctic Southern Ocean The Antarctic Indian |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_relation |
vital:6493 http://vital.seals.ac.za:8080/vital/access/manager/Repository/vital:6493 http://hdl.handle.net/10962/d1004477 |
_version_ |
1766117777334075392 |