Upper-layer circulation in the eastern Equatorial and South Atlantic Ocean in January–March 1995.

International audience The upper-layer circulation in the eastern basin of the South Atlantic was studied from hydrographic and direct velocity measurements along WOCE lines A11, A13 and A14. A13 and A14 provide quasi-meridional samplings of the equatorial, subequatorial and subtropical circulation...

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Published in:Deep Sea Research Part I: Oceanographic Research Papers
Main Authors: Mercier, Herlé, Arhan, Michel, Lutjeharms, Johann R. E.
Other Authors: Laboratoire de physique des océans (LPO), Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS), Department of Oceanography Cape Town, University of Cape Town
Format: Article in Journal/Newspaper
Language:English
Published: HAL CCSD 2003
Subjects:
Online Access:https://hal.archives-ouvertes.fr/hal-00271267
https://doi.org/10.1016/S0967-0637(03)00071-2
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spelling ftccsdartic:oai:HAL:hal-00271267v1 2023-05-15T18:21:17+02:00 Upper-layer circulation in the eastern Equatorial and South Atlantic Ocean in January–March 1995. Mercier, Herlé Arhan, Michel Lutjeharms, Johann R. E. Laboratoire de physique des océans (LPO) Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS) Department of Oceanography Cape Town University of Cape Town 2003-07 https://hal.archives-ouvertes.fr/hal-00271267 https://doi.org/10.1016/S0967-0637(03)00071-2 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/S0967-0637(03)00071-2 hal-00271267 https://hal.archives-ouvertes.fr/hal-00271267 doi:10.1016/S0967-0637(03)00071-2 ISSN: 0967-0637 Deep Sea Research Part I: Oceanographic Research Papers https://hal.archives-ouvertes.fr/hal-00271267 Deep Sea Research Part I: Oceanographic Research Papers, Elsevier, 2003, 50 (7), pp.863-887. &#x27E8;10.1016/S0967-0637(03)00071-2&#x27E9; Equatorial Atlantic South Atlantic Circulation Current Hydrography [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography info:eu-repo/semantics/article Journal articles 2003 ftccsdartic https://doi.org/10.1016/S0967-0637(03)00071-2 2021-10-17T02:10:37Z International audience The upper-layer circulation in the eastern basin of the South Atlantic was studied from hydrographic and direct velocity measurements along WOCE lines A11, A13 and A14. A13 and A14 provide quasi-meridional samplings of the equatorial, subequatorial and subtropical circulation regimes. A13 was carried out along the African coast at about 600 km offshore from it, and A14 along the nominal longitude 9°W. A11 intersects the Cape Basin between 46°S in the west and 30°S in the east. Transport estimates were derived from direct velocity measurements and a box inverse model. In the equatorial eastern Atlantic, the Equatorial Undercurrent (EUC) transport decreases from 25×106 m3 s−1 at 9°W to 13×106 m3 s−1 at 5°E. Re-circulations of the EUC into the northern and equatorial branches of the South Equatorial Current (SEC) are evidenced at 5°E and quantified. In the tropical Atlantic, we estimate 7.5×106 and 4.2×106 m3 s−1 for the transports at 9°W of the South Equatorial Undercurrent (SEUC) and South Equatorial Countercurrent (SECC), respectively. Both the SEUC and SECC extend vertically down to intermediate depths and contribute to the northern limb of the Angola Gyre. The Angola Current transport is estimated to be 16±5×106 m3 s−1 for σ1<32.1 at 13°S. South of the Angola Gyre, the transports show an apparent cyclonic circulation, developed mostly at the intermediate level. The water mass properties suggest that it is, at least partially, a re-circulation of the Benguela Current. Further south and for the subtropical gyre, we estimate 10±5×106 m3 s−1 for the transport of the South Atlantic Current across 9°W and 28±4×106 m3 s−1 for the transport of the Benguela Current at 10°E for σ1<32.1. Article in Journal/Newspaper South Atlantic Ocean Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) Deep Sea Research Part I: Oceanographic Research Papers 50 7 863 887
institution Open Polar
collection Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe)
op_collection_id ftccsdartic
language English
topic Equatorial Atlantic
South Atlantic
Circulation
Current
Hydrography
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography
spellingShingle Equatorial Atlantic
South Atlantic
Circulation
Current
Hydrography
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography
Mercier, Herlé
Arhan, Michel
Lutjeharms, Johann R. E.
Upper-layer circulation in the eastern Equatorial and South Atlantic Ocean in January–March 1995.
topic_facet Equatorial Atlantic
South Atlantic
Circulation
Current
Hydrography
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography
description International audience The upper-layer circulation in the eastern basin of the South Atlantic was studied from hydrographic and direct velocity measurements along WOCE lines A11, A13 and A14. A13 and A14 provide quasi-meridional samplings of the equatorial, subequatorial and subtropical circulation regimes. A13 was carried out along the African coast at about 600 km offshore from it, and A14 along the nominal longitude 9°W. A11 intersects the Cape Basin between 46°S in the west and 30°S in the east. Transport estimates were derived from direct velocity measurements and a box inverse model. In the equatorial eastern Atlantic, the Equatorial Undercurrent (EUC) transport decreases from 25×106 m3 s−1 at 9°W to 13×106 m3 s−1 at 5°E. Re-circulations of the EUC into the northern and equatorial branches of the South Equatorial Current (SEC) are evidenced at 5°E and quantified. In the tropical Atlantic, we estimate 7.5×106 and 4.2×106 m3 s−1 for the transports at 9°W of the South Equatorial Undercurrent (SEUC) and South Equatorial Countercurrent (SECC), respectively. Both the SEUC and SECC extend vertically down to intermediate depths and contribute to the northern limb of the Angola Gyre. The Angola Current transport is estimated to be 16±5×106 m3 s−1 for σ1<32.1 at 13°S. South of the Angola Gyre, the transports show an apparent cyclonic circulation, developed mostly at the intermediate level. The water mass properties suggest that it is, at least partially, a re-circulation of the Benguela Current. Further south and for the subtropical gyre, we estimate 10±5×106 m3 s−1 for the transport of the South Atlantic Current across 9°W and 28±4×106 m3 s−1 for the transport of the Benguela Current at 10°E for σ1<32.1.
author2 Laboratoire de physique des océans (LPO)
Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)
Department of Oceanography Cape Town
University of Cape Town
format Article in Journal/Newspaper
author Mercier, Herlé
Arhan, Michel
Lutjeharms, Johann R. E.
author_facet Mercier, Herlé
Arhan, Michel
Lutjeharms, Johann R. E.
author_sort Mercier, Herlé
title Upper-layer circulation in the eastern Equatorial and South Atlantic Ocean in January–March 1995.
title_short Upper-layer circulation in the eastern Equatorial and South Atlantic Ocean in January–March 1995.
title_full Upper-layer circulation in the eastern Equatorial and South Atlantic Ocean in January–March 1995.
title_fullStr Upper-layer circulation in the eastern Equatorial and South Atlantic Ocean in January–March 1995.
title_full_unstemmed Upper-layer circulation in the eastern Equatorial and South Atlantic Ocean in January–March 1995.
title_sort upper-layer circulation in the eastern equatorial and south atlantic ocean in january–march 1995.
publisher HAL CCSD
publishDate 2003
url https://hal.archives-ouvertes.fr/hal-00271267
https://doi.org/10.1016/S0967-0637(03)00071-2
genre South Atlantic Ocean
genre_facet South Atlantic Ocean
op_source ISSN: 0967-0637
Deep Sea Research Part I: Oceanographic Research Papers
https://hal.archives-ouvertes.fr/hal-00271267
Deep Sea Research Part I: Oceanographic Research Papers, Elsevier, 2003, 50 (7), pp.863-887. &#x27E8;10.1016/S0967-0637(03)00071-2&#x27E9;
op_relation info:eu-repo/semantics/altIdentifier/doi/10.1016/S0967-0637(03)00071-2
hal-00271267
https://hal.archives-ouvertes.fr/hal-00271267
doi:10.1016/S0967-0637(03)00071-2
op_doi https://doi.org/10.1016/S0967-0637(03)00071-2
container_title Deep Sea Research Part I: Oceanographic Research Papers
container_volume 50
container_issue 7
container_start_page 863
op_container_end_page 887
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