Heat budget in the North Atlantic subpolar gyre: Impacts of atmospheric weather regimes on the 1995 warming event
International audience In the mid 1990s, the North Atlantic subpolar gyre has shown a dramatic warming event that has been thoroughly investigated from observations and numerical simulations. Some studies suggest that it was due to an interannual, wind-driven weakening and shrinking of the gyre that...
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Online Access: | https://hal.science/hal-01126661 https://doi.org/10.1016/j.pocean.2014.10.001 |
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ftsorbonneuniv:oai:HAL:hal-01126661v1 2023-12-17T10:33:04+01:00 Heat budget in the North Atlantic subpolar gyre: Impacts of atmospheric weather regimes on the 1995 warming event Barrier, Nicolas Deshayes, Julie Tréguier, Anne-Marie Cassou, Christophe 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) ICEMASA University of Cape Town Centre Européen de Recherche et de Formation Avancée en Calcul Scientifique (CERFACS) 2015-01 https://hal.science/hal-01126661 https://doi.org/10.1016/j.pocean.2014.10.001 en eng HAL CCSD Elsevier info:eu-repo/semantics/altIdentifier/doi/10.1016/j.pocean.2014.10.001 hal-01126661 https://hal.science/hal-01126661 BIBCODE: fdi:010063926 doi:10.1016/j.pocean.2014.10.001 ISSN: 0079-6611 Progress in Oceanography https://hal.science/hal-01126661 Progress in Oceanography, 2015, 130, pp.75-90. ⟨10.1016/j.pocean.2014.10.001⟩ [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere info:eu-repo/semantics/article Journal articles 2015 ftsorbonneuniv https://doi.org/10.1016/j.pocean.2014.10.001 2023-11-21T23:55:48Z International audience In the mid 1990s, the North Atlantic subpolar gyre has shown a dramatic warming event that has been thoroughly investigated from observations and numerical simulations. Some studies suggest that it was due to an interannual, wind-driven weakening and shrinking of the gyre that facilitated the penetration of warm Atlantic Water, the weakening of the gyre being attributed to changes in the North Atlantic Oscillation (NAO) and in the East Atlantic Pattern, which are the two dominant modes of atmospheric variability in the North Atlantic. However, other studies suggest that the warming event was due to a decadal, buoyancy-driven strengthening of the meridional overturning circulation and subsequent intensification of the poleward heat transport, in response to the positive NAO conditions of 1988–1995. To reconcile this discrepancy, the heat budget in the North Atlantic subpolar gyre is reconstructed from four ocean hindcast simulations sharing the same modelling platform but using different settings. The novelty of this work is the decomposition of the subpolar gyre into a western and an eastern subregion, which is motivated by water mass distribution around Reykjanes Ridge and by the fact that deep convection only occurs in the western subpolar gyre.In the western subpolar gyre, the 1995 warming event is the decadal, baroclinic ocean response to positive NAO conditions from 1988 to 1995. The latter induced increased surface heat loss in the Labrador Sea that intensified deep convection hence strengthened the meridional overturning circulation and the associated poleward heat transport. In the eastern subregion, a concomittant warming is induced by an interannual, barotropic adjustment of the gyre circulation to an abrupt switch from positive NAO conditions in winter 1995 to negative NAO conditions in winter 1996. Indeed, the gyre response to negative NAO conditions is a cyclonic intergyre-gyre that increases northward volume and heat transports at the southeastern limit of the subpolar ... Article in Journal/Newspaper Labrador Sea North Atlantic North Atlantic oscillation HAL Sorbonne Université Reykjanes ENVELOPE(-22.250,-22.250,65.467,65.467) Progress in Oceanography 130 75 90 |
institution |
Open Polar |
collection |
HAL Sorbonne Université |
op_collection_id |
ftsorbonneuniv |
language |
English |
topic |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere |
spellingShingle |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere Barrier, Nicolas Deshayes, Julie Tréguier, Anne-Marie Cassou, Christophe Heat budget in the North Atlantic subpolar gyre: Impacts of atmospheric weather regimes on the 1995 warming event |
topic_facet |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere |
description |
International audience In the mid 1990s, the North Atlantic subpolar gyre has shown a dramatic warming event that has been thoroughly investigated from observations and numerical simulations. Some studies suggest that it was due to an interannual, wind-driven weakening and shrinking of the gyre that facilitated the penetration of warm Atlantic Water, the weakening of the gyre being attributed to changes in the North Atlantic Oscillation (NAO) and in the East Atlantic Pattern, which are the two dominant modes of atmospheric variability in the North Atlantic. However, other studies suggest that the warming event was due to a decadal, buoyancy-driven strengthening of the meridional overturning circulation and subsequent intensification of the poleward heat transport, in response to the positive NAO conditions of 1988–1995. To reconcile this discrepancy, the heat budget in the North Atlantic subpolar gyre is reconstructed from four ocean hindcast simulations sharing the same modelling platform but using different settings. The novelty of this work is the decomposition of the subpolar gyre into a western and an eastern subregion, which is motivated by water mass distribution around Reykjanes Ridge and by the fact that deep convection only occurs in the western subpolar gyre.In the western subpolar gyre, the 1995 warming event is the decadal, baroclinic ocean response to positive NAO conditions from 1988 to 1995. The latter induced increased surface heat loss in the Labrador Sea that intensified deep convection hence strengthened the meridional overturning circulation and the associated poleward heat transport. In the eastern subregion, a concomittant warming is induced by an interannual, barotropic adjustment of the gyre circulation to an abrupt switch from positive NAO conditions in winter 1995 to negative NAO conditions in winter 1996. Indeed, the gyre response to negative NAO conditions is a cyclonic intergyre-gyre that increases northward volume and heat transports at the southeastern limit of the subpolar ... |
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) ICEMASA University of Cape Town Centre Européen de Recherche et de Formation Avancée en Calcul Scientifique (CERFACS) |
format |
Article in Journal/Newspaper |
author |
Barrier, Nicolas Deshayes, Julie Tréguier, Anne-Marie Cassou, Christophe |
author_facet |
Barrier, Nicolas Deshayes, Julie Tréguier, Anne-Marie Cassou, Christophe |
author_sort |
Barrier, Nicolas |
title |
Heat budget in the North Atlantic subpolar gyre: Impacts of atmospheric weather regimes on the 1995 warming event |
title_short |
Heat budget in the North Atlantic subpolar gyre: Impacts of atmospheric weather regimes on the 1995 warming event |
title_full |
Heat budget in the North Atlantic subpolar gyre: Impacts of atmospheric weather regimes on the 1995 warming event |
title_fullStr |
Heat budget in the North Atlantic subpolar gyre: Impacts of atmospheric weather regimes on the 1995 warming event |
title_full_unstemmed |
Heat budget in the North Atlantic subpolar gyre: Impacts of atmospheric weather regimes on the 1995 warming event |
title_sort |
heat budget in the north atlantic subpolar gyre: impacts of atmospheric weather regimes on the 1995 warming event |
publisher |
HAL CCSD |
publishDate |
2015 |
url |
https://hal.science/hal-01126661 https://doi.org/10.1016/j.pocean.2014.10.001 |
long_lat |
ENVELOPE(-22.250,-22.250,65.467,65.467) |
geographic |
Reykjanes |
geographic_facet |
Reykjanes |
genre |
Labrador Sea North Atlantic North Atlantic oscillation |
genre_facet |
Labrador Sea North Atlantic North Atlantic oscillation |
op_source |
ISSN: 0079-6611 Progress in Oceanography https://hal.science/hal-01126661 Progress in Oceanography, 2015, 130, pp.75-90. ⟨10.1016/j.pocean.2014.10.001⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1016/j.pocean.2014.10.001 hal-01126661 https://hal.science/hal-01126661 BIBCODE: fdi:010063926 doi:10.1016/j.pocean.2014.10.001 |
op_doi |
https://doi.org/10.1016/j.pocean.2014.10.001 |
container_title |
Progress in Oceanography |
container_volume |
130 |
container_start_page |
75 |
op_container_end_page |
90 |
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1785586952908570624 |