Dissipation Rate Estimates from Microstructure and Finescale Internal Wave Observations along the A25 Greenland–Portugal OVIDE Line
International audience A total of 96 finestructure and 30 microstructure full-depth vertical profiles were collected along the A25 Greenland–Portugal Observatoire de la Variabilité Interannuelle et Décennale en Atlantique Nord (OVIDE) hydrographic line in 2008. The microstructure of the horizontal v...
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ftunivbrest:oai:HAL:hal-01128174v1 2024-01-14T10:07:19+01:00 Dissipation Rate Estimates from Microstructure and Finescale Internal Wave Observations along the A25 Greenland–Portugal OVIDE Line Ferron, Bruno Kokoszka, Florian Mercier, Herlé Lherminier, Pascale 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) 2014-11 https://hal.science/hal-01128174 https://hal.science/hal-01128174/document https://hal.science/hal-01128174/file/33628.pdf https://doi.org/10.1175/JTECH-D-14-00036.1 en eng HAL CCSD American Meteorological Society info:eu-repo/semantics/altIdentifier/doi/10.1175/JTECH-D-14-00036.1 hal-01128174 https://hal.science/hal-01128174 https://hal.science/hal-01128174/document https://hal.science/hal-01128174/file/33628.pdf doi:10.1175/JTECH-D-14-00036.1 info:eu-repo/semantics/OpenAccess ISSN: 0739-0572 EISSN: 1520-0426 Journal of Atmospheric and Oceanic Technology https://hal.science/hal-01128174 Journal of Atmospheric and Oceanic Technology, 2014, 31 (11), pp.2530-2543. ⟨10.1175/JTECH-D-14-00036.1⟩ Diapycnal mixing [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography info:eu-repo/semantics/article Journal articles 2014 ftunivbrest https://doi.org/10.1175/JTECH-D-14-00036.1 2023-12-19T23:36:15Z International audience A total of 96 finestructure and 30 microstructure full-depth vertical profiles were collected along the A25 Greenland–Portugal Observatoire de la Variabilité Interannuelle et Décennale en Atlantique Nord (OVIDE) hydrographic line in 2008. The microstructure of the horizontal velocity was used to calculate turbulent kinetic energy dissipation rates εvmp, where vmp refers to the vertical microstructure profiler. The lowest dissipation values (εvmp < 0.5 × 10−10 W kg−1) are found below 2000 m in the Iberian Abyssal Plain and in the center of the Irminger basin; the largest values (>5 × 10−10 W kg−1) are found in the main thermocline, around the Reykjanes Ridge, and in a 1000-m-thick layer above the bottom near 48°N. The finestructure of density was used to estimate isopycnal strain and that of the lowered acoustic Doppler current profiler to estimate the vertical shear of horizontal velocities. Strain and shear were used to estimate dissipation rates εG03 (Gregg et al.) associated with the internal wave field. The shear-to-strain ratio correction term of the finescale parameterization εG03 brings the fine- and microscale estimates of the dissipation rate into better agreement as Polzin et al. found. The latitude/buoyancy frequency term slightly improves the parameterization for weakly stratified waters. Correction term εG03 is consistent with εvmp within a factor of 4.5 over 95% of the profiles. This good consistency suggests that most of the turbulent activity recorded in this dataset is due to the internal wave field. The canonical globally averaged diffusivity value of order 10−4 m2 s−1 needed to maintain the global abyssal stratification (Munk) is only reached on the flank of the Reykjanes Ridge and in the region around 48°N. Article in Journal/Newspaper Greenland Université de Bretagne Occidentale: HAL Greenland Irminger Basin ENVELOPE(-36.000,-36.000,61.000,61.000) Munk ENVELOPE(-95.993,-95.993,55.979,55.979) Reykjanes ENVELOPE(-22.250,-22.250,65.467,65.467) Journal of Atmospheric and Oceanic Technology 31 11 2530 2543 |
institution |
Open Polar |
collection |
Université de Bretagne Occidentale: HAL |
op_collection_id |
ftunivbrest |
language |
English |
topic |
Diapycnal mixing [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
spellingShingle |
Diapycnal mixing [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography Ferron, Bruno Kokoszka, Florian Mercier, Herlé Lherminier, Pascale Dissipation Rate Estimates from Microstructure and Finescale Internal Wave Observations along the A25 Greenland–Portugal OVIDE Line |
topic_facet |
Diapycnal mixing [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
description |
International audience A total of 96 finestructure and 30 microstructure full-depth vertical profiles were collected along the A25 Greenland–Portugal Observatoire de la Variabilité Interannuelle et Décennale en Atlantique Nord (OVIDE) hydrographic line in 2008. The microstructure of the horizontal velocity was used to calculate turbulent kinetic energy dissipation rates εvmp, where vmp refers to the vertical microstructure profiler. The lowest dissipation values (εvmp < 0.5 × 10−10 W kg−1) are found below 2000 m in the Iberian Abyssal Plain and in the center of the Irminger basin; the largest values (>5 × 10−10 W kg−1) are found in the main thermocline, around the Reykjanes Ridge, and in a 1000-m-thick layer above the bottom near 48°N. The finestructure of density was used to estimate isopycnal strain and that of the lowered acoustic Doppler current profiler to estimate the vertical shear of horizontal velocities. Strain and shear were used to estimate dissipation rates εG03 (Gregg et al.) associated with the internal wave field. The shear-to-strain ratio correction term of the finescale parameterization εG03 brings the fine- and microscale estimates of the dissipation rate into better agreement as Polzin et al. found. The latitude/buoyancy frequency term slightly improves the parameterization for weakly stratified waters. Correction term εG03 is consistent with εvmp within a factor of 4.5 over 95% of the profiles. This good consistency suggests that most of the turbulent activity recorded in this dataset is due to the internal wave field. The canonical globally averaged diffusivity value of order 10−4 m2 s−1 needed to maintain the global abyssal stratification (Munk) is only reached on the flank of the Reykjanes Ridge and in the region around 48°N. |
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) |
format |
Article in Journal/Newspaper |
author |
Ferron, Bruno Kokoszka, Florian Mercier, Herlé Lherminier, Pascale |
author_facet |
Ferron, Bruno Kokoszka, Florian Mercier, Herlé Lherminier, Pascale |
author_sort |
Ferron, Bruno |
title |
Dissipation Rate Estimates from Microstructure and Finescale Internal Wave Observations along the A25 Greenland–Portugal OVIDE Line |
title_short |
Dissipation Rate Estimates from Microstructure and Finescale Internal Wave Observations along the A25 Greenland–Portugal OVIDE Line |
title_full |
Dissipation Rate Estimates from Microstructure and Finescale Internal Wave Observations along the A25 Greenland–Portugal OVIDE Line |
title_fullStr |
Dissipation Rate Estimates from Microstructure and Finescale Internal Wave Observations along the A25 Greenland–Portugal OVIDE Line |
title_full_unstemmed |
Dissipation Rate Estimates from Microstructure and Finescale Internal Wave Observations along the A25 Greenland–Portugal OVIDE Line |
title_sort |
dissipation rate estimates from microstructure and finescale internal wave observations along the a25 greenland–portugal ovide line |
publisher |
HAL CCSD |
publishDate |
2014 |
url |
https://hal.science/hal-01128174 https://hal.science/hal-01128174/document https://hal.science/hal-01128174/file/33628.pdf https://doi.org/10.1175/JTECH-D-14-00036.1 |
long_lat |
ENVELOPE(-36.000,-36.000,61.000,61.000) ENVELOPE(-95.993,-95.993,55.979,55.979) ENVELOPE(-22.250,-22.250,65.467,65.467) |
geographic |
Greenland Irminger Basin Munk Reykjanes |
geographic_facet |
Greenland Irminger Basin Munk Reykjanes |
genre |
Greenland |
genre_facet |
Greenland |
op_source |
ISSN: 0739-0572 EISSN: 1520-0426 Journal of Atmospheric and Oceanic Technology https://hal.science/hal-01128174 Journal of Atmospheric and Oceanic Technology, 2014, 31 (11), pp.2530-2543. ⟨10.1175/JTECH-D-14-00036.1⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1175/JTECH-D-14-00036.1 hal-01128174 https://hal.science/hal-01128174 https://hal.science/hal-01128174/document https://hal.science/hal-01128174/file/33628.pdf doi:10.1175/JTECH-D-14-00036.1 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1175/JTECH-D-14-00036.1 |
container_title |
Journal of Atmospheric and Oceanic Technology |
container_volume |
31 |
container_issue |
11 |
container_start_page |
2530 |
op_container_end_page |
2543 |
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1788061726763122688 |