Enhanced Diapycnal Diffusivity in Intrusive Regions of the Drake Passage
Direct measurements of oceanic turbulent parameters were taken upstream of and across Drake Passage, in the region of the Subantarctic and Polar Fronts. Values of turbulent kinetic energy dissipation rate ε estimated by microstructure are up to two orders of magnitude lower than previously published...
| Main Authors: | , , , , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
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American Meteorological Society
2017
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| Online Access: | http://hdl.handle.net/1721.1/106308 https://orcid.org/0000-0002-4152-7285 |
| _version_ | 1826208836226121728 |
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| author | Laurent, Louis St. Owens, Breck Thurnherr, Andreas M. Toole, John M. Merrifield, Sophia Tiare |
| author2 | Woods Hole Oceanographic Institution |
| author_facet | Woods Hole Oceanographic Institution Laurent, Louis St. Owens, Breck Thurnherr, Andreas M. Toole, John M. Merrifield, Sophia Tiare |
| author_sort | Laurent, Louis St. |
| collection | MIT |
| description | Direct measurements of oceanic turbulent parameters were taken upstream of and across Drake Passage, in the region of the Subantarctic and Polar Fronts. Values of turbulent kinetic energy dissipation rate ε estimated by microstructure are up to two orders of magnitude lower than previously published estimates in the upper 1000 m. Turbulence levels in Drake Passage are systematically higher than values upstream, regardless of season. The dissipation of thermal variance χ is enhanced at middepth throughout the surveys, with the highest values found in northern Drake Passage, where water mass variability is the most pronounced. Using the density ratio, evidence for double-diffusive instability is presented. Subject to double-diffusive physics, the estimates of diffusivity using the Osborn–Cox method are larger than ensemble statistics based on ε and the buoyancy frequency. |
| first_indexed | 2024-09-23T14:13:05Z |
| format | Article |
| id | mit-1721.1/106308 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T14:13:05Z |
| publishDate | 2017 |
| publisher | American Meteorological Society |
| record_format | dspace |
| spelling | mit-1721.1/1063082024-06-26T20:40:09Z Enhanced Diapycnal Diffusivity in Intrusive Regions of the Drake Passage Laurent, Louis St. Owens, Breck Thurnherr, Andreas M. Toole, John M. Merrifield, Sophia Tiare Woods Hole Oceanographic Institution Merrifield, Sophia Tiare Direct measurements of oceanic turbulent parameters were taken upstream of and across Drake Passage, in the region of the Subantarctic and Polar Fronts. Values of turbulent kinetic energy dissipation rate ε estimated by microstructure are up to two orders of magnitude lower than previously published estimates in the upper 1000 m. Turbulence levels in Drake Passage are systematically higher than values upstream, regardless of season. The dissipation of thermal variance χ is enhanced at middepth throughout the surveys, with the highest values found in northern Drake Passage, where water mass variability is the most pronounced. Using the density ratio, evidence for double-diffusive instability is presented. Subject to double-diffusive physics, the estimates of diffusivity using the Osborn–Cox method are larger than ensemble statistics based on ε and the buoyancy frequency. National Science Foundation (U.S.) 2017-01-09T20:51:36Z 2017-01-09T20:51:36Z 2016-04 2015-04 Article http://purl.org/eprint/type/JournalArticle 0022-3670 1520-0485 http://hdl.handle.net/1721.1/106308 Merrifield, Sophia T. et al. “Enhanced Diapycnal Diffusivity in Intrusive Regions of the Drake Passage.” Journal of Physical Oceanography 46.4 (2016): 1309–1321. © 2016 American Meteorological Society https://orcid.org/0000-0002-4152-7285 en_US http://dx.doi.org/10.1175/jpo-d-15-0068.1 Journal of Physical Oceanography Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Meteorological Society American Meteorological Society |
| spellingShingle | Laurent, Louis St. Owens, Breck Thurnherr, Andreas M. Toole, John M. Merrifield, Sophia Tiare Enhanced Diapycnal Diffusivity in Intrusive Regions of the Drake Passage |
| title | Enhanced Diapycnal Diffusivity in Intrusive Regions of the Drake Passage |
| title_full | Enhanced Diapycnal Diffusivity in Intrusive Regions of the Drake Passage |
| title_fullStr | Enhanced Diapycnal Diffusivity in Intrusive Regions of the Drake Passage |
| title_full_unstemmed | Enhanced Diapycnal Diffusivity in Intrusive Regions of the Drake Passage |
| title_short | Enhanced Diapycnal Diffusivity in Intrusive Regions of the Drake Passage |
| title_sort | enhanced diapycnal diffusivity in intrusive regions of the drake passage |
| url | http://hdl.handle.net/1721.1/106308 https://orcid.org/0000-0002-4152-7285 |
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