Annual cycle of turbulent dissipation estimated from seagliders
The rate of dissipation of turbulent kinetic energy is estimated using Seaglider observations of vertical water velocity in the midlatitude North Atlantic. This estimate is based on the large‐eddy method, allowing the use of measurements of turbulent energy at large scales O(1–10 m) to diagnose the...
Published in: | Geophysical Research Letters |
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Online Access: | http://nora.nerc.ac.uk/id/eprint/521197/ https://nora.nerc.ac.uk/id/eprint/521197/1/Annual%20Cycle%20of%20Turbulent%20Dissipation%20Estimated%20from%20Seagliders%20-%20Evans%20-%202018%20-%20Geophysical%20Research%20Letters%20-%20Wiley%20Online%20Library.html https://doi.org/10.1029/2018GL079966 |
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ftnerc:oai:nora.nerc.ac.uk:521197 2023-05-15T17:32:03+02:00 Annual cycle of turbulent dissipation estimated from seagliders Evans, Dafydd Gwyn Lucas, Natasha Sarah Hemsley, Victoria Frajka-Williams, Eleanor Naveira Garabato, Alberto C. Martin, Adrian Painter, Stuart C. Inall, Mark E. Palmer, Matthew R. 2018 text http://nora.nerc.ac.uk/id/eprint/521197/ https://nora.nerc.ac.uk/id/eprint/521197/1/Annual%20Cycle%20of%20Turbulent%20Dissipation%20Estimated%20from%20Seagliders%20-%20Evans%20-%202018%20-%20Geophysical%20Research%20Letters%20-%20Wiley%20Online%20Library.html https://doi.org/10.1029/2018GL079966 en eng https://nora.nerc.ac.uk/id/eprint/521197/1/Annual%20Cycle%20of%20Turbulent%20Dissipation%20Estimated%20from%20Seagliders%20-%20Evans%20-%202018%20-%20Geophysical%20Research%20Letters%20-%20Wiley%20Online%20Library.html Evans, Dafydd Gwyn orcid:0000-0002-6328-4093 Lucas, Natasha Sarah; Hemsley, Victoria; Frajka-Williams, Eleanor orcid:0000-0001-8773-7838 Naveira Garabato, Alberto C.; Martin, Adrian orcid:0000-0002-1202-8612 Painter, Stuart C.; Inall, Mark E.; Palmer, Matthew R. 2018 Annual cycle of turbulent dissipation estimated from seagliders. Geophysical Research Letters, 45 (19). 10,560-10,569. https://doi.org/10.1029/2018GL079966 <https://doi.org/10.1029/2018GL079966> cc_by_4 CC-BY Publication - Article PeerReviewed 2018 ftnerc https://doi.org/10.1029/2018GL079966 2023-02-04T19:47:13Z The rate of dissipation of turbulent kinetic energy is estimated using Seaglider observations of vertical water velocity in the midlatitude North Atlantic. This estimate is based on the large‐eddy method, allowing the use of measurements of turbulent energy at large scales O(1–10 m) to diagnose the rate of energy dissipated through viscous processes at scales O(1 mm). The Seaglider data considered here were obtained in a region of high stratification (1 × 10−4<N < 1×10−2s−1), where previous implementations of this method fail. The large‐eddy method is generalized to high‐stratification by high‐pass filtering vertical velocity with a cutoff dependent on the local buoyancy frequency, producing a year‐long time series of dissipation rate spanning the uppermost 1,000 m with subdaily resolution. This is compared to the dissipation rate estimated from a moored 600 kHz acoustic Doppler current profiler. The variability of the Seaglider‐based dissipation correlates with one‐dimensional scalings of wind‐ and buoyancy‐driven mixed‐layer turbulence. Plain Language Summary Measuring ocean turbulence is crucial for understanding how heat and carbon dioxide are transferred from the atmosphere to the deep ocean. However, measurements of ocean turbulence are sparse. Here autonomous Seagliders are used to estimate turbulence in the surface kilometer of the North Atlantic Ocean. Using an estimate of the vertical water velocity from the flight of the Seaglider through the water, we estimate turbulence by assuming the energy of the largest turbulent fluctuations is representative of the energy dissipated at molecular scales. This approach has been used previously in an ocean region where the vertical gradient of density is small. Our results show that this previous approach fails when the vertical density gradient increases, as it does not account for other processes that are unrelated to turbulence. We introduce a generalized method that isolates only the turbulent processes by accounting for the strength of the vertical ... Article in Journal/Newspaper North Atlantic Natural Environment Research Council: NERC Open Research Archive Geophysical Research Letters 45 19 10,560 10,569 |
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Open Polar |
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Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
description |
The rate of dissipation of turbulent kinetic energy is estimated using Seaglider observations of vertical water velocity in the midlatitude North Atlantic. This estimate is based on the large‐eddy method, allowing the use of measurements of turbulent energy at large scales O(1–10 m) to diagnose the rate of energy dissipated through viscous processes at scales O(1 mm). The Seaglider data considered here were obtained in a region of high stratification (1 × 10−4<N < 1×10−2s−1), where previous implementations of this method fail. The large‐eddy method is generalized to high‐stratification by high‐pass filtering vertical velocity with a cutoff dependent on the local buoyancy frequency, producing a year‐long time series of dissipation rate spanning the uppermost 1,000 m with subdaily resolution. This is compared to the dissipation rate estimated from a moored 600 kHz acoustic Doppler current profiler. The variability of the Seaglider‐based dissipation correlates with one‐dimensional scalings of wind‐ and buoyancy‐driven mixed‐layer turbulence. Plain Language Summary Measuring ocean turbulence is crucial for understanding how heat and carbon dioxide are transferred from the atmosphere to the deep ocean. However, measurements of ocean turbulence are sparse. Here autonomous Seagliders are used to estimate turbulence in the surface kilometer of the North Atlantic Ocean. Using an estimate of the vertical water velocity from the flight of the Seaglider through the water, we estimate turbulence by assuming the energy of the largest turbulent fluctuations is representative of the energy dissipated at molecular scales. This approach has been used previously in an ocean region where the vertical gradient of density is small. Our results show that this previous approach fails when the vertical density gradient increases, as it does not account for other processes that are unrelated to turbulence. We introduce a generalized method that isolates only the turbulent processes by accounting for the strength of the vertical ... |
format |
Article in Journal/Newspaper |
author |
Evans, Dafydd Gwyn Lucas, Natasha Sarah Hemsley, Victoria Frajka-Williams, Eleanor Naveira Garabato, Alberto C. Martin, Adrian Painter, Stuart C. Inall, Mark E. Palmer, Matthew R. |
spellingShingle |
Evans, Dafydd Gwyn Lucas, Natasha Sarah Hemsley, Victoria Frajka-Williams, Eleanor Naveira Garabato, Alberto C. Martin, Adrian Painter, Stuart C. Inall, Mark E. Palmer, Matthew R. Annual cycle of turbulent dissipation estimated from seagliders |
author_facet |
Evans, Dafydd Gwyn Lucas, Natasha Sarah Hemsley, Victoria Frajka-Williams, Eleanor Naveira Garabato, Alberto C. Martin, Adrian Painter, Stuart C. Inall, Mark E. Palmer, Matthew R. |
author_sort |
Evans, Dafydd Gwyn |
title |
Annual cycle of turbulent dissipation estimated from seagliders |
title_short |
Annual cycle of turbulent dissipation estimated from seagliders |
title_full |
Annual cycle of turbulent dissipation estimated from seagliders |
title_fullStr |
Annual cycle of turbulent dissipation estimated from seagliders |
title_full_unstemmed |
Annual cycle of turbulent dissipation estimated from seagliders |
title_sort |
annual cycle of turbulent dissipation estimated from seagliders |
publishDate |
2018 |
url |
http://nora.nerc.ac.uk/id/eprint/521197/ https://nora.nerc.ac.uk/id/eprint/521197/1/Annual%20Cycle%20of%20Turbulent%20Dissipation%20Estimated%20from%20Seagliders%20-%20Evans%20-%202018%20-%20Geophysical%20Research%20Letters%20-%20Wiley%20Online%20Library.html https://doi.org/10.1029/2018GL079966 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_relation |
https://nora.nerc.ac.uk/id/eprint/521197/1/Annual%20Cycle%20of%20Turbulent%20Dissipation%20Estimated%20from%20Seagliders%20-%20Evans%20-%202018%20-%20Geophysical%20Research%20Letters%20-%20Wiley%20Online%20Library.html Evans, Dafydd Gwyn orcid:0000-0002-6328-4093 Lucas, Natasha Sarah; Hemsley, Victoria; Frajka-Williams, Eleanor orcid:0000-0001-8773-7838 Naveira Garabato, Alberto C.; Martin, Adrian orcid:0000-0002-1202-8612 Painter, Stuart C.; Inall, Mark E.; Palmer, Matthew R. 2018 Annual cycle of turbulent dissipation estimated from seagliders. Geophysical Research Letters, 45 (19). 10,560-10,569. https://doi.org/10.1029/2018GL079966 <https://doi.org/10.1029/2018GL079966> |
op_rights |
cc_by_4 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1029/2018GL079966 |
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Geophysical Research Letters |
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45 |
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19 |
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10,560 |
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10,569 |
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1766129971139444736 |