On the generation and role of eddy variability in the central North Atlantic Ocean: Results from surface drifters satellite altimetry and numerical modelling
Sources of near-surface oceanic variability in the central North Atlantic are identified from a combined analysis of climatology, surface drifter, and Geosat altimeter data as well as eddy-resolving math formula and math formula Community Modeling Effort North Atlantic model results. Both observatio...
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AGU (American Geophysical Union)
1994
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ftoceanrep:oai:oceanrep.geomar.de:5400 2023-05-15T17:25:17+02:00 On the generation and role of eddy variability in the central North Atlantic Ocean: Results from surface drifters satellite altimetry and numerical modelling Beckmann, Aike Böning, Claus W. Brügge, Bernd Stammer, Detlef 1994 text https://oceanrep.geomar.de/id/eprint/5400/ https://oceanrep.geomar.de/id/eprint/5400/1/Beckman_B%C3%B6ning%281994%29.pdf https://doi.org/10.1029/94JC01654 en eng AGU (American Geophysical Union) https://oceanrep.geomar.de/id/eprint/5400/1/Beckman_B%C3%B6ning%281994%29.pdf Beckmann, A., Böning, C. W. , Brügge, B. and Stammer, D. (1994) On the generation and role of eddy variability in the central North Atlantic Ocean: Results from surface drifters satellite altimetry and numerical modelling. Open Access Journal of Geophysical Research: Oceans, 99 (C10). pp. 20381-20391. DOI 10.1029/94JC01654 <https://doi.org/10.1029/94JC01654>. doi:10.1029/94JC01654 info:eu-repo/semantics/openAccess Article PeerReviewed 1994 ftoceanrep https://doi.org/10.1029/94JC01654 2023-04-07T14:51:03Z Sources of near-surface oceanic variability in the central North Atlantic are identified from a combined analysis of climatology, surface drifter, and Geosat altimeter data as well as eddy-resolving math formula and math formula Community Modeling Effort North Atlantic model results. Both observational and numerical methods give a consistent picture of the concentration of mesoscale variability along the mean zonal flow bands. Three areas of high eddy energy can be found in all observational data sets: the North Equatorial Current, the North Atlantic Current, and the Azores Current. With increasing horizontal resolution the numerical models give a more realistic representation of the variability in the first two regimes, while no improvement is found with respect to the Azores Current Frontal Zone. Examination of the upper ocean hydrographic structure indicates baroclinic instability to be the main mechanism of eddy generation and suggests that the model deficiencies in the Azores Current area are related to deficiencies in the mean hydrographic fields. A linear instability analysis of the numerical model output reveals that instability based on the velocity shear between the mixed layer and the interior is also important for the generation of the mid-ocean variability, indicating a potential role of the mixed layer representation for the model. The math formula model successfully simulates the northward decrease of eddy length scales observed in the altimeter data, which follow a linear relationship with the first baroclinic Rossby radius. An analysis of the eddy-mean flow interaction terms and the energy budget indicates a release of mean potential energy by downgradient fluxes of heat in the main frontal zones. At the same time the North Atlantic Current is found to be supported by convergent eddy fluxes of zonal momentum. Article in Journal/Newspaper north atlantic current North Atlantic OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) Journal of Geophysical Research 99 C10 20381 |
institution |
Open Polar |
collection |
OceanRep (GEOMAR Helmholtz Centre für Ocean Research Kiel) |
op_collection_id |
ftoceanrep |
language |
English |
description |
Sources of near-surface oceanic variability in the central North Atlantic are identified from a combined analysis of climatology, surface drifter, and Geosat altimeter data as well as eddy-resolving math formula and math formula Community Modeling Effort North Atlantic model results. Both observational and numerical methods give a consistent picture of the concentration of mesoscale variability along the mean zonal flow bands. Three areas of high eddy energy can be found in all observational data sets: the North Equatorial Current, the North Atlantic Current, and the Azores Current. With increasing horizontal resolution the numerical models give a more realistic representation of the variability in the first two regimes, while no improvement is found with respect to the Azores Current Frontal Zone. Examination of the upper ocean hydrographic structure indicates baroclinic instability to be the main mechanism of eddy generation and suggests that the model deficiencies in the Azores Current area are related to deficiencies in the mean hydrographic fields. A linear instability analysis of the numerical model output reveals that instability based on the velocity shear between the mixed layer and the interior is also important for the generation of the mid-ocean variability, indicating a potential role of the mixed layer representation for the model. The math formula model successfully simulates the northward decrease of eddy length scales observed in the altimeter data, which follow a linear relationship with the first baroclinic Rossby radius. An analysis of the eddy-mean flow interaction terms and the energy budget indicates a release of mean potential energy by downgradient fluxes of heat in the main frontal zones. At the same time the North Atlantic Current is found to be supported by convergent eddy fluxes of zonal momentum. |
format |
Article in Journal/Newspaper |
author |
Beckmann, Aike Böning, Claus W. Brügge, Bernd Stammer, Detlef |
spellingShingle |
Beckmann, Aike Böning, Claus W. Brügge, Bernd Stammer, Detlef On the generation and role of eddy variability in the central North Atlantic Ocean: Results from surface drifters satellite altimetry and numerical modelling |
author_facet |
Beckmann, Aike Böning, Claus W. Brügge, Bernd Stammer, Detlef |
author_sort |
Beckmann, Aike |
title |
On the generation and role of eddy variability in the central North Atlantic Ocean: Results from surface drifters satellite altimetry and numerical modelling |
title_short |
On the generation and role of eddy variability in the central North Atlantic Ocean: Results from surface drifters satellite altimetry and numerical modelling |
title_full |
On the generation and role of eddy variability in the central North Atlantic Ocean: Results from surface drifters satellite altimetry and numerical modelling |
title_fullStr |
On the generation and role of eddy variability in the central North Atlantic Ocean: Results from surface drifters satellite altimetry and numerical modelling |
title_full_unstemmed |
On the generation and role of eddy variability in the central North Atlantic Ocean: Results from surface drifters satellite altimetry and numerical modelling |
title_sort |
on the generation and role of eddy variability in the central north atlantic ocean: results from surface drifters satellite altimetry and numerical modelling |
publisher |
AGU (American Geophysical Union) |
publishDate |
1994 |
url |
https://oceanrep.geomar.de/id/eprint/5400/ https://oceanrep.geomar.de/id/eprint/5400/1/Beckman_B%C3%B6ning%281994%29.pdf https://doi.org/10.1029/94JC01654 |
genre |
north atlantic current North Atlantic |
genre_facet |
north atlantic current North Atlantic |
op_relation |
https://oceanrep.geomar.de/id/eprint/5400/1/Beckman_B%C3%B6ning%281994%29.pdf Beckmann, A., Böning, C. W. , Brügge, B. and Stammer, D. (1994) On the generation and role of eddy variability in the central North Atlantic Ocean: Results from surface drifters satellite altimetry and numerical modelling. Open Access Journal of Geophysical Research: Oceans, 99 (C10). pp. 20381-20391. DOI 10.1029/94JC01654 <https://doi.org/10.1029/94JC01654>. doi:10.1029/94JC01654 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.1029/94JC01654 |
container_title |
Journal of Geophysical Research |
container_volume |
99 |
container_issue |
C10 |
container_start_page |
20381 |
_version_ |
1766116670677450752 |