Zonal jets in the equatorial Atlantic Ocean
18 pages, 15 figures, 1 table, 1 appendix: Harmonic analysis We use position data from Argo floats, smoothed out over 400 km × 200 km zonal ellipses and interpolated onto a 0.5° grid, to investigate the zonal jet structure of the flow field at the sea surface and on three subsurface layers (Central...
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ftcsic:oai:digital.csic.es:10261/117579 2024-02-11T09:57:30+01:00 Zonal jets in the equatorial Atlantic Ocean Rosell Fieschi, Miquel Pelegrí, Josep Lluís Gourrion, Jérôme 2015-01 http://hdl.handle.net/10261/117579 https://doi.org/10.1016/j.pocean.2014.08.008 unknown Elsevier https://doi.org/10.1016/j.pocean.2014.08.008 issn: 0079-6611 Progress in Oceanography 130: 1-18 (2015) http://hdl.handle.net/10261/117579 doi:10.1016/j.pocean.2014.08.008 none artículo http://purl.org/coar/resource_type/c_6501 2015 ftcsic https://doi.org/10.1016/j.pocean.2014.08.008 2024-01-16T10:08:25Z 18 pages, 15 figures, 1 table, 1 appendix: Harmonic analysis We use position data from Argo floats, smoothed out over 400 km × 200 km zonal ellipses and interpolated onto a 0.5° grid, to investigate the zonal jet structure of the flow field at the sea surface and on three subsurface layers (Central Waters, CW, 200 m; Antarctic Intermediate Waters, AAIW, 1000 m; upper North Atlantic Deep Waters, uNADW, 1500 m) in the equatorial Atlantic Ocean (15°S to 15°N). The annual-mean fields exhibit narrow zonal jets, typically 4–5° wide at the sea surface and only 2° at the subsurface levels, with directions alternating in latitude and maximum speeds about 0.5 m s−1 at the surface, 0.1 m s−1 at CW and uNADW, and 0.03 m s−1 at AAIW. The available data also allows us to explore the seasonal variability of these jets at the surface and AAIW levels. The surface currents are dominated by an annual cycle between 4°N and 10°N and, to a lesser degree, by a semi-annual contribution close to the equator. This variability is an outcome of evolving zonal recirculations, with the North Equatorial Countercurrent (NECC) arising from the diversion of the northern branch of the South Equatorial Current (nSEC); the diversion begins in the eastern Atlantic and propagates west between April and August, following the Inter-Tropical Convergence Zone (ITCZ). The AAIW current field is largely affected by westward propagating anomalies, most visible near 3°S, 0°, 3°N and 7°N, which give rise to current reversals. Annual averaging produces the illusion of more (5 instead of 3) and slower (peak values about 0.03 m s−1 instead of 0.1 m s−1) jets than found on any month Funding for this work comes from the Ministerio de Ciencia e Innovación, Spain, through projects Transmisión de perfiladores Argo en la Cuenca de Canarias (ARGO-Canarias, Ref. CTM2009-08462-E/MAR), Memoria Oceánica del Clima (MOC2, Ref. CTM2008-06438-C02-01) and Tipping Corners in the Meridional Overturning Circulation (TIC-MOC, Ref. CTM2011-28867). Miquel Rosell-Fieschi would like ... Article in Journal/Newspaper Antarc* Antarctic North Atlantic Digital.CSIC (Spanish National Research Council) Antarctic Progress in Oceanography 130 1 18 |
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Digital.CSIC (Spanish National Research Council) |
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ftcsic |
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18 pages, 15 figures, 1 table, 1 appendix: Harmonic analysis We use position data from Argo floats, smoothed out over 400 km × 200 km zonal ellipses and interpolated onto a 0.5° grid, to investigate the zonal jet structure of the flow field at the sea surface and on three subsurface layers (Central Waters, CW, 200 m; Antarctic Intermediate Waters, AAIW, 1000 m; upper North Atlantic Deep Waters, uNADW, 1500 m) in the equatorial Atlantic Ocean (15°S to 15°N). The annual-mean fields exhibit narrow zonal jets, typically 4–5° wide at the sea surface and only 2° at the subsurface levels, with directions alternating in latitude and maximum speeds about 0.5 m s−1 at the surface, 0.1 m s−1 at CW and uNADW, and 0.03 m s−1 at AAIW. The available data also allows us to explore the seasonal variability of these jets at the surface and AAIW levels. The surface currents are dominated by an annual cycle between 4°N and 10°N and, to a lesser degree, by a semi-annual contribution close to the equator. This variability is an outcome of evolving zonal recirculations, with the North Equatorial Countercurrent (NECC) arising from the diversion of the northern branch of the South Equatorial Current (nSEC); the diversion begins in the eastern Atlantic and propagates west between April and August, following the Inter-Tropical Convergence Zone (ITCZ). The AAIW current field is largely affected by westward propagating anomalies, most visible near 3°S, 0°, 3°N and 7°N, which give rise to current reversals. Annual averaging produces the illusion of more (5 instead of 3) and slower (peak values about 0.03 m s−1 instead of 0.1 m s−1) jets than found on any month Funding for this work comes from the Ministerio de Ciencia e Innovación, Spain, through projects Transmisión de perfiladores Argo en la Cuenca de Canarias (ARGO-Canarias, Ref. CTM2009-08462-E/MAR), Memoria Oceánica del Clima (MOC2, Ref. CTM2008-06438-C02-01) and Tipping Corners in the Meridional Overturning Circulation (TIC-MOC, Ref. CTM2011-28867). Miquel Rosell-Fieschi would like ... |
format |
Article in Journal/Newspaper |
author |
Rosell Fieschi, Miquel Pelegrí, Josep Lluís Gourrion, Jérôme |
spellingShingle |
Rosell Fieschi, Miquel Pelegrí, Josep Lluís Gourrion, Jérôme Zonal jets in the equatorial Atlantic Ocean |
author_facet |
Rosell Fieschi, Miquel Pelegrí, Josep Lluís Gourrion, Jérôme |
author_sort |
Rosell Fieschi, Miquel |
title |
Zonal jets in the equatorial Atlantic Ocean |
title_short |
Zonal jets in the equatorial Atlantic Ocean |
title_full |
Zonal jets in the equatorial Atlantic Ocean |
title_fullStr |
Zonal jets in the equatorial Atlantic Ocean |
title_full_unstemmed |
Zonal jets in the equatorial Atlantic Ocean |
title_sort |
zonal jets in the equatorial atlantic ocean |
publisher |
Elsevier |
publishDate |
2015 |
url |
http://hdl.handle.net/10261/117579 https://doi.org/10.1016/j.pocean.2014.08.008 |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic North Atlantic |
genre_facet |
Antarc* Antarctic North Atlantic |
op_relation |
https://doi.org/10.1016/j.pocean.2014.08.008 issn: 0079-6611 Progress in Oceanography 130: 1-18 (2015) http://hdl.handle.net/10261/117579 doi:10.1016/j.pocean.2014.08.008 |
op_rights |
none |
op_doi |
https://doi.org/10.1016/j.pocean.2014.08.008 |
container_title |
Progress in Oceanography |
container_volume |
130 |
container_start_page |
1 |
op_container_end_page |
18 |
_version_ |
1790609796514185216 |