Mechanisms of variability in a convective basin
International audience An idealized model for a convective basin is used to investigate the mechanisms of variability of the formation and export of dense water. In this model, which consists of two isopycnic layers, dense water formation is induced by surface buoyancy loss in the interior, which is...
Published in: | Journal of Marine Research |
---|---|
Main Authors: | , , |
Other Authors: | , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2009
|
Subjects: | |
Online Access: | https://hal.science/hal-00455770 https://doi.org/10.1357/002224009789954757 |
id |
ftsorbonneuniv:oai:HAL:hal-00455770v1 |
---|---|
record_format |
openpolar |
spelling |
ftsorbonneuniv:oai:HAL:hal-00455770v1 2024-09-15T18:17:12+00:00 Mechanisms of variability in a convective basin Deshayes, Julie Straneo, F. Spall, M.A. Department of Physical Oceanography Woods Hole Oceanographic Institution (WHOI) 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) 2009-05 https://hal.science/hal-00455770 https://doi.org/10.1357/002224009789954757 en eng HAL CCSD Yale University info:eu-repo/semantics/altIdentifier/doi/10.1357/002224009789954757 hal-00455770 https://hal.science/hal-00455770 doi:10.1357/002224009789954757 ISSN: 0022-2402 EISSN: 1543-9542 Journal of marine research https://hal.science/hal-00455770 Journal of marine research, 2009, 67 (3), pp.273-303. ⟨10.1357/002224009789954757⟩ MERIDIONAL OVERTURNING CIRCULATION WESTERN BOUNDARY CURRENT LABRADOR SEA-WATER ATLANTIC THERMOHALINE CIRCULATION NORTH-ATLANTIC DEEP-WATER HEAT-TRANSPORT IRMINGER SEAS OCEAN RESTRATIFICATION [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography info:eu-repo/semantics/article Journal articles 2009 ftsorbonneuniv https://doi.org/10.1357/002224009789954757 2024-07-25T23:47:36Z International audience An idealized model for a convective basin is used to investigate the mechanisms of variability of the formation and export of dense water. In this model, which consists of two isopycnic layers, dense water formation is induced by surface buoyancy loss in the interior, which is at rest. Newly formed dense water is transmitted to the surrounding boundary current through parameterized eddy fluxes. Variability in the formation and export of dense water is due to changes in the two main drivers: variations in the surface buoyancy fluxes and variations in the large-scale wind via a barotropic boundary current. Numerical integrations of the nonlinear model, with parameters and forcings corresponding to the Labrador Sea, show that the rate of dense water formation in the interior of the basin is strongly affected by changes in the buoyancy forcing, but not significantly affected by seasonal to interannual changes in the wind-driven barotropic boundary current. The basin tends to integrate the buoyancy forcing variability with a memory time scale set by eddies, which is decadal for the Labrador Sea. Variability in dense water export, on the contrary, is strongly affected by changes in the wind-driven barotropic boundary current but hardly affected by changes in buoyancy forcing. Indeed changes in the transport of dense water at the basin outflow are dominated by those at the basin inflow, which, in this model, are directly related to fluctuations in the wind-driven barotropic boundary current. These results, which are consistent with analytical solutions of the linear model, suggest that fluctuations in the surface buoyancy fluxes in the interior Labrador Sea have little impact on the interannual variability of the dense water transport by the Deep Western Boundary Current at the outflow of the Labrador Sea, which is dominated by fluctuations in the wind-driven North Atlantic subpolar gyre, but influence the formation and export of recently ventilated waters. Article in Journal/Newspaper Labrador Sea North Atlantic Deep Water North Atlantic HAL Sorbonne Université Journal of Marine Research 67 3 273 303 |
institution |
Open Polar |
collection |
HAL Sorbonne Université |
op_collection_id |
ftsorbonneuniv |
language |
English |
topic |
MERIDIONAL OVERTURNING CIRCULATION WESTERN BOUNDARY CURRENT LABRADOR SEA-WATER ATLANTIC THERMOHALINE CIRCULATION NORTH-ATLANTIC DEEP-WATER HEAT-TRANSPORT IRMINGER SEAS OCEAN RESTRATIFICATION [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
spellingShingle |
MERIDIONAL OVERTURNING CIRCULATION WESTERN BOUNDARY CURRENT LABRADOR SEA-WATER ATLANTIC THERMOHALINE CIRCULATION NORTH-ATLANTIC DEEP-WATER HEAT-TRANSPORT IRMINGER SEAS OCEAN RESTRATIFICATION [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography Deshayes, Julie Straneo, F. Spall, M.A. Mechanisms of variability in a convective basin |
topic_facet |
MERIDIONAL OVERTURNING CIRCULATION WESTERN BOUNDARY CURRENT LABRADOR SEA-WATER ATLANTIC THERMOHALINE CIRCULATION NORTH-ATLANTIC DEEP-WATER HEAT-TRANSPORT IRMINGER SEAS OCEAN RESTRATIFICATION [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
description |
International audience An idealized model for a convective basin is used to investigate the mechanisms of variability of the formation and export of dense water. In this model, which consists of two isopycnic layers, dense water formation is induced by surface buoyancy loss in the interior, which is at rest. Newly formed dense water is transmitted to the surrounding boundary current through parameterized eddy fluxes. Variability in the formation and export of dense water is due to changes in the two main drivers: variations in the surface buoyancy fluxes and variations in the large-scale wind via a barotropic boundary current. Numerical integrations of the nonlinear model, with parameters and forcings corresponding to the Labrador Sea, show that the rate of dense water formation in the interior of the basin is strongly affected by changes in the buoyancy forcing, but not significantly affected by seasonal to interannual changes in the wind-driven barotropic boundary current. The basin tends to integrate the buoyancy forcing variability with a memory time scale set by eddies, which is decadal for the Labrador Sea. Variability in dense water export, on the contrary, is strongly affected by changes in the wind-driven barotropic boundary current but hardly affected by changes in buoyancy forcing. Indeed changes in the transport of dense water at the basin outflow are dominated by those at the basin inflow, which, in this model, are directly related to fluctuations in the wind-driven barotropic boundary current. These results, which are consistent with analytical solutions of the linear model, suggest that fluctuations in the surface buoyancy fluxes in the interior Labrador Sea have little impact on the interannual variability of the dense water transport by the Deep Western Boundary Current at the outflow of the Labrador Sea, which is dominated by fluctuations in the wind-driven North Atlantic subpolar gyre, but influence the formation and export of recently ventilated waters. |
author2 |
Department of Physical Oceanography Woods Hole Oceanographic Institution (WHOI) 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) |
format |
Article in Journal/Newspaper |
author |
Deshayes, Julie Straneo, F. Spall, M.A. |
author_facet |
Deshayes, Julie Straneo, F. Spall, M.A. |
author_sort |
Deshayes, Julie |
title |
Mechanisms of variability in a convective basin |
title_short |
Mechanisms of variability in a convective basin |
title_full |
Mechanisms of variability in a convective basin |
title_fullStr |
Mechanisms of variability in a convective basin |
title_full_unstemmed |
Mechanisms of variability in a convective basin |
title_sort |
mechanisms of variability in a convective basin |
publisher |
HAL CCSD |
publishDate |
2009 |
url |
https://hal.science/hal-00455770 https://doi.org/10.1357/002224009789954757 |
genre |
Labrador Sea North Atlantic Deep Water North Atlantic |
genre_facet |
Labrador Sea North Atlantic Deep Water North Atlantic |
op_source |
ISSN: 0022-2402 EISSN: 1543-9542 Journal of marine research https://hal.science/hal-00455770 Journal of marine research, 2009, 67 (3), pp.273-303. ⟨10.1357/002224009789954757⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1357/002224009789954757 hal-00455770 https://hal.science/hal-00455770 doi:10.1357/002224009789954757 |
op_doi |
https://doi.org/10.1357/002224009789954757 |
container_title |
Journal of Marine Research |
container_volume |
67 |
container_issue |
3 |
container_start_page |
273 |
op_container_end_page |
303 |
_version_ |
1810455195279163392 |