Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap?
The southward-flowing deep limb of the Atlantic meridional overturning circulation is composed of both the deep western boundary current (DWBC) and interior pathways. The latter are fed by ‘‘leakiness’’ from the DWBC in the Newfoundland Basin. However, the cause of this leakiness has not yet been ex...
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ftcdlib:oai:escholarship.org:ark:/13030/qt1zv6h673 2023-07-16T03:59:37+02:00 Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? Solodoch, Aviv McWilliams, James C Stewart, Andrew L Gula, Jonathan Renault, Lionel 1989 - 2016 2020-07-01 application/pdf https://escholarship.org/uc/item/1zv6h673 unknown eScholarship, University of California qt1zv6h673 https://escholarship.org/uc/item/1zv6h673 CC-BY Journal of Physical Oceanography, vol 50, iss 7 Oceanography Maritime Engineering article 2020 ftcdlib 2023-06-26T18:00:12Z The southward-flowing deep limb of the Atlantic meridional overturning circulation is composed of both the deep western boundary current (DWBC) and interior pathways. The latter are fed by ‘‘leakiness’’ from the DWBC in the Newfoundland Basin. However, the cause of this leakiness has not yet been explored mechanistically. Here the statistics and dynamics of the DWBC leakiness in the Newfoundland Basin are explored using two float datasets and a high-resolution numerical model. The float leakiness around Flemish Cap is found to be concentrated in several areas (hot spots) that are collocated with bathymetric curvature and steepening. Numerical particle advection experiments reveal that the Lagrangian mean velocity is offshore at these hot spots, while Lagrangian variability is minimal locally. Furthermore, model Eulerian mean streamlines separate from the DWBC to the interior at the leakiness hot spots. This suggests that the leakiness of Lagrangian particles is primarily accomplished by an Eulerian mean flow across isobaths, though eddies serve to transfer around 50% of the Lagrangian particles to the leakiness hot spots via chaotic advection, and rectified eddy transport accounts for around 50% of the offshore flow along the southern face of Flemish Cap. Analysis of the model’s energy and potential vorticity budgets suggests that the flow is baroclinically unstable after separation, but that the resulting eddies induce modest modifications of the mean potential vorticity along streamlines. These results suggest that mean uncompensated leakiness occurs mostly through inertial separation, for which a scaling analysis is presented. Implications for leakiness of other major boundary current systems are discussed. Article in Journal/Newspaper Newfoundland University of California: eScholarship |
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University of California: eScholarship |
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language |
unknown |
topic |
Oceanography Maritime Engineering |
spellingShingle |
Oceanography Maritime Engineering Solodoch, Aviv McWilliams, James C Stewart, Andrew L Gula, Jonathan Renault, Lionel Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? |
topic_facet |
Oceanography Maritime Engineering |
description |
The southward-flowing deep limb of the Atlantic meridional overturning circulation is composed of both the deep western boundary current (DWBC) and interior pathways. The latter are fed by ‘‘leakiness’’ from the DWBC in the Newfoundland Basin. However, the cause of this leakiness has not yet been explored mechanistically. Here the statistics and dynamics of the DWBC leakiness in the Newfoundland Basin are explored using two float datasets and a high-resolution numerical model. The float leakiness around Flemish Cap is found to be concentrated in several areas (hot spots) that are collocated with bathymetric curvature and steepening. Numerical particle advection experiments reveal that the Lagrangian mean velocity is offshore at these hot spots, while Lagrangian variability is minimal locally. Furthermore, model Eulerian mean streamlines separate from the DWBC to the interior at the leakiness hot spots. This suggests that the leakiness of Lagrangian particles is primarily accomplished by an Eulerian mean flow across isobaths, though eddies serve to transfer around 50% of the Lagrangian particles to the leakiness hot spots via chaotic advection, and rectified eddy transport accounts for around 50% of the offshore flow along the southern face of Flemish Cap. Analysis of the model’s energy and potential vorticity budgets suggests that the flow is baroclinically unstable after separation, but that the resulting eddies induce modest modifications of the mean potential vorticity along streamlines. These results suggest that mean uncompensated leakiness occurs mostly through inertial separation, for which a scaling analysis is presented. Implications for leakiness of other major boundary current systems are discussed. |
format |
Article in Journal/Newspaper |
author |
Solodoch, Aviv McWilliams, James C Stewart, Andrew L Gula, Jonathan Renault, Lionel |
author_facet |
Solodoch, Aviv McWilliams, James C Stewart, Andrew L Gula, Jonathan Renault, Lionel |
author_sort |
Solodoch, Aviv |
title |
Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? |
title_short |
Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? |
title_full |
Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? |
title_fullStr |
Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? |
title_full_unstemmed |
Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? Why Does the DeepWestern Boundary Current “Leak” Around Flemish Cap? |
title_sort |
why does the deepwestern boundary current “leak” around flemish cap? why does the deepwestern boundary current “leak” around flemish cap? |
publisher |
eScholarship, University of California |
publishDate |
2020 |
url |
https://escholarship.org/uc/item/1zv6h673 |
op_coverage |
1989 - 2016 |
genre |
Newfoundland |
genre_facet |
Newfoundland |
op_source |
Journal of Physical Oceanography, vol 50, iss 7 |
op_relation |
qt1zv6h673 https://escholarship.org/uc/item/1zv6h673 |
op_rights |
CC-BY |
_version_ |
1771547692704464896 |