Density Staircases Are Disappearing in the Canada Basin of the Arctic Ocean
International audience In the Canada Basin of the Arctic Ocean, warm and salty Atlantic-origin Water (AW) lies in the intermediate layer (250–800 m) below a colder and fresher surface layer. It results in a depth range where vertical thermohaline gradients are propitious to double-diffusion. Indeed,...
Published in: | Journal of Geophysical Research: Oceans |
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Online Access: | https://hal.science/hal-03910680 https://hal.science/hal-03910680/document https://hal.science/hal-03910680/file/JGR%20Oceans%20-%202022%20-%20M%20nesguen%20-%20Density%20Staircases%20Are%20Disappearing%20in%20the%20Canada%20Basin%20of%20the%20Arctic%20Ocean.pdf https://doi.org/10.1029/2022JC018877 |
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ftunivrennes1hal:oai:HAL:hal-03910680v1 2023-12-10T09:45:33+01:00 Density Staircases Are Disappearing in the Canada Basin of the Arctic Ocean Ménesguen, Claire Lique, Camille Caspar‐cohen, Zoé Océan Dynamique Observations Analyse (ODYSSEY) Université de Bretagne Occidentale - UFR Sciences et Techniques (UBO UFR ST) Université de Brest (UBO)-Université de Brest (UBO)-Université de Rennes (UR)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Inria Rennes – Bretagne Atlantique Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-IMT Atlantique (IMT Atlantique) Institut Mines-Télécom Paris (IMT)-Institut Mines-Télécom Paris (IMT) Laboratoire d'Océanographie Physique et Spatiale (LOPS) Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS) 2022-11 https://hal.science/hal-03910680 https://hal.science/hal-03910680/document https://hal.science/hal-03910680/file/JGR%20Oceans%20-%202022%20-%20M%20nesguen%20-%20Density%20Staircases%20Are%20Disappearing%20in%20the%20Canada%20Basin%20of%20the%20Arctic%20Ocean.pdf https://doi.org/10.1029/2022JC018877 en eng HAL CCSD Wiley-Blackwell info:eu-repo/semantics/altIdentifier/doi/10.1029/2022JC018877 hal-03910680 https://hal.science/hal-03910680 https://hal.science/hal-03910680/document https://hal.science/hal-03910680/file/JGR%20Oceans%20-%202022%20-%20M%20nesguen%20-%20Density%20Staircases%20Are%20Disappearing%20in%20the%20Canada%20Basin%20of%20the%20Arctic%20Ocean.pdf doi:10.1029/2022JC018877 http://creativecommons.org/licenses/by-nc-sa/ info:eu-repo/semantics/OpenAccess ISSN: 2169-9275 EISSN: 2169-9291 Journal of Geophysical Research. Oceans https://hal.science/hal-03910680 Journal of Geophysical Research. Oceans, 2022, 127 (11), pp.1-17. ⟨10.1029/2022JC018877⟩ [SDU]Sciences of the Universe [physics] [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere info:eu-repo/semantics/article Journal articles 2022 ftunivrennes1hal https://doi.org/10.1029/2022JC018877 2023-11-14T23:44:40Z International audience In the Canada Basin of the Arctic Ocean, warm and salty Atlantic-origin Water (AW) lies in the intermediate layer (250–800 m) below a colder and fresher surface layer. It results in a depth range where vertical thermohaline gradients are propitious to double-diffusion. Indeed, thermohaline staircases are commonly observed and associated with double-diffusive processes. Using observations from the Beaufort Gyre Exploration Project large database and Ice-Tethered Profilers, we document the presence of density staircases in the 300–700 m depth range with a striking strong spatial and temporal coherence. However, since 2007, a progressive smoothing of these staircases has occurred, beginning from the western half of the basin. Quantifying this evolution, we find that a general pattern is a clear evolution over time from numerous thicksteps (≃40 m) with sharp interfaces to fewer and thinner steps (≃30 m) with smoother interfaces. After 2014, marked density staircases have almost disappeared in most of the Canada Basin. The vanishing of staircases occurs over a few years and coincides with modifications of the large scale circulation and thermohaline large scale horizontal gradients. As the small scale thermohaline structures are thought to play an important role for the vertical and horizontal exchanges of heat within the Canada Basin, the disappearance of the steps may impact the heat distribution at depth, with potential consequences for the evolution of the sea ice cover. Article in Journal/Newspaper Arctic Arctic Ocean canada basin Sea ice Université de Rennes 1: Publications scientifiques (HAL) Arctic Arctic Ocean Canada Journal of Geophysical Research: Oceans 127 11 |
institution |
Open Polar |
collection |
Université de Rennes 1: Publications scientifiques (HAL) |
op_collection_id |
ftunivrennes1hal |
language |
English |
topic |
[SDU]Sciences of the Universe [physics] [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere |
spellingShingle |
[SDU]Sciences of the Universe [physics] [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere Ménesguen, Claire Lique, Camille Caspar‐cohen, Zoé Density Staircases Are Disappearing in the Canada Basin of the Arctic Ocean |
topic_facet |
[SDU]Sciences of the Universe [physics] [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere |
description |
International audience In the Canada Basin of the Arctic Ocean, warm and salty Atlantic-origin Water (AW) lies in the intermediate layer (250–800 m) below a colder and fresher surface layer. It results in a depth range where vertical thermohaline gradients are propitious to double-diffusion. Indeed, thermohaline staircases are commonly observed and associated with double-diffusive processes. Using observations from the Beaufort Gyre Exploration Project large database and Ice-Tethered Profilers, we document the presence of density staircases in the 300–700 m depth range with a striking strong spatial and temporal coherence. However, since 2007, a progressive smoothing of these staircases has occurred, beginning from the western half of the basin. Quantifying this evolution, we find that a general pattern is a clear evolution over time from numerous thicksteps (≃40 m) with sharp interfaces to fewer and thinner steps (≃30 m) with smoother interfaces. After 2014, marked density staircases have almost disappeared in most of the Canada Basin. The vanishing of staircases occurs over a few years and coincides with modifications of the large scale circulation and thermohaline large scale horizontal gradients. As the small scale thermohaline structures are thought to play an important role for the vertical and horizontal exchanges of heat within the Canada Basin, the disappearance of the steps may impact the heat distribution at depth, with potential consequences for the evolution of the sea ice cover. |
author2 |
Océan Dynamique Observations Analyse (ODYSSEY) Université de Bretagne Occidentale - UFR Sciences et Techniques (UBO UFR ST) Université de Brest (UBO)-Université de Brest (UBO)-Université de Rennes (UR)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Inria Rennes – Bretagne Atlantique Institut National de Recherche en Informatique et en Automatique (Inria)-Institut National de Recherche en Informatique et en Automatique (Inria)-IMT Atlantique (IMT Atlantique) Institut Mines-Télécom Paris (IMT)-Institut Mines-Télécom Paris (IMT) Laboratoire d'Océanographie Physique et Spatiale (LOPS) Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Ménesguen, Claire Lique, Camille Caspar‐cohen, Zoé |
author_facet |
Ménesguen, Claire Lique, Camille Caspar‐cohen, Zoé |
author_sort |
Ménesguen, Claire |
title |
Density Staircases Are Disappearing in the Canada Basin of the Arctic Ocean |
title_short |
Density Staircases Are Disappearing in the Canada Basin of the Arctic Ocean |
title_full |
Density Staircases Are Disappearing in the Canada Basin of the Arctic Ocean |
title_fullStr |
Density Staircases Are Disappearing in the Canada Basin of the Arctic Ocean |
title_full_unstemmed |
Density Staircases Are Disappearing in the Canada Basin of the Arctic Ocean |
title_sort |
density staircases are disappearing in the canada basin of the arctic ocean |
publisher |
HAL CCSD |
publishDate |
2022 |
url |
https://hal.science/hal-03910680 https://hal.science/hal-03910680/document https://hal.science/hal-03910680/file/JGR%20Oceans%20-%202022%20-%20M%20nesguen%20-%20Density%20Staircases%20Are%20Disappearing%20in%20the%20Canada%20Basin%20of%20the%20Arctic%20Ocean.pdf https://doi.org/10.1029/2022JC018877 |
geographic |
Arctic Arctic Ocean Canada |
geographic_facet |
Arctic Arctic Ocean Canada |
genre |
Arctic Arctic Ocean canada basin Sea ice |
genre_facet |
Arctic Arctic Ocean canada basin Sea ice |
op_source |
ISSN: 2169-9275 EISSN: 2169-9291 Journal of Geophysical Research. Oceans https://hal.science/hal-03910680 Journal of Geophysical Research. Oceans, 2022, 127 (11), pp.1-17. ⟨10.1029/2022JC018877⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2022JC018877 hal-03910680 https://hal.science/hal-03910680 https://hal.science/hal-03910680/document https://hal.science/hal-03910680/file/JGR%20Oceans%20-%202022%20-%20M%20nesguen%20-%20Density%20Staircases%20Are%20Disappearing%20in%20the%20Canada%20Basin%20of%20the%20Arctic%20Ocean.pdf doi:10.1029/2022JC018877 |
op_rights |
http://creativecommons.org/licenses/by-nc-sa/ info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1029/2022JC018877 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
127 |
container_issue |
11 |
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1784888831259967488 |