Rates and mechanisms of turbulent dissipation and mixing in the Southern Ocean: Results from the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES)
The spatial distribution of turbulent dissipation rates and internal wave field characteristics is analysed across two contrasting regimes of the Antarctic Circumpolar Current (ACC), using microstructure and finestructure data collected as part of the Diapycnal and Isopycnal Mixing Experiment in the...
Published in: | Journal of Geophysical Research: Oceans |
---|---|
Main Authors: | , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2013
|
Subjects: | |
Online Access: | https://eprints.soton.ac.uk/352457/ https://eprints.soton.ac.uk/352457/1/jgrc20217_Sheen.pdf |
id |
ftsouthampton:oai:eprints.soton.ac.uk:352457 |
---|---|
record_format |
openpolar |
spelling |
ftsouthampton:oai:eprints.soton.ac.uk:352457 2023-08-27T04:04:27+02:00 Rates and mechanisms of turbulent dissipation and mixing in the Southern Ocean: Results from the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) Sheen, K.L. Brearley, J. A. Naveira Garabato, A.C. Waterman, S. Smeed, D.A. Ledwell, J.R. Meredith, M.P. St. Laurent, L. Thurnherr, A.M. Toole, J.M. Watson, A.J. 2013-06 text https://eprints.soton.ac.uk/352457/ https://eprints.soton.ac.uk/352457/1/jgrc20217_Sheen.pdf en English eng https://eprints.soton.ac.uk/352457/1/jgrc20217_Sheen.pdf Sheen, K.L., Brearley, J. A., Naveira Garabato, A.C., Waterman, S., Smeed, D.A., Ledwell, J.R., Meredith, M.P., St. Laurent, L., Thurnherr, A.M., Toole, J.M. and Watson, A.J. (2013) Rates and mechanisms of turbulent dissipation and mixing in the Southern Ocean: Results from the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES). Journal of Geophysical Research: Oceans, 118 (6), 2774-2792. (doi:10.1002/jgrc.20217 <http://dx.doi.org/10.1002/jgrc.20217>). Article PeerReviewed 2013 ftsouthampton https://doi.org/10.1002/jgrc.20217 2023-08-03T22:20:16Z The spatial distribution of turbulent dissipation rates and internal wave field characteristics is analysed across two contrasting regimes of the Antarctic Circumpolar Current (ACC), using microstructure and finestructure data collected as part of the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES). Mid-depth turbulent dissipation rates are found to increase from O (1×10-10 W kg-1) in the Southeast Pacific to O (1×10-9 W kg-1) in the Scotia Sea, typically reaching 3×10-9 W kg-1 within a kilometre of the seabed. Enhanced levels of turbulent mixing are associated with strong near-bottom flows, rough topography, and regions where the internal wave field is found to have enhanced energy, a less-inertial frequency content and a dominance of upward-propagating energy. These results strongly suggest that bottom-generated internal waves play a major role in determining the spatial distribution of turbulent dissipation in the ACC. The energy flux associated with the bottom internal wave generation process is calculated using wave radiation theory, and found to vary between 0.8 mWm-2 in the Southeast Pacific and 14 m W m-2 in the Scotia Sea. Typically, 10-30% of this energy is found to dissipate within 1 km of the seabed. Comparison between turbulent dissipation rates inferred from finestructure parameterizations and microstructure-derived estimates suggests a significant departure from wave-wave interaction physics in the near-field of wave generation sites. Article in Journal/Newspaper Antarc* Antarctic Scotia Sea Southern Ocean University of Southampton: e-Prints Soton Antarctic Pacific Scotia Sea Southern Ocean The Antarctic Journal of Geophysical Research: Oceans 118 6 2774 2792 |
institution |
Open Polar |
collection |
University of Southampton: e-Prints Soton |
op_collection_id |
ftsouthampton |
language |
English |
description |
The spatial distribution of turbulent dissipation rates and internal wave field characteristics is analysed across two contrasting regimes of the Antarctic Circumpolar Current (ACC), using microstructure and finestructure data collected as part of the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES). Mid-depth turbulent dissipation rates are found to increase from O (1×10-10 W kg-1) in the Southeast Pacific to O (1×10-9 W kg-1) in the Scotia Sea, typically reaching 3×10-9 W kg-1 within a kilometre of the seabed. Enhanced levels of turbulent mixing are associated with strong near-bottom flows, rough topography, and regions where the internal wave field is found to have enhanced energy, a less-inertial frequency content and a dominance of upward-propagating energy. These results strongly suggest that bottom-generated internal waves play a major role in determining the spatial distribution of turbulent dissipation in the ACC. The energy flux associated with the bottom internal wave generation process is calculated using wave radiation theory, and found to vary between 0.8 mWm-2 in the Southeast Pacific and 14 m W m-2 in the Scotia Sea. Typically, 10-30% of this energy is found to dissipate within 1 km of the seabed. Comparison between turbulent dissipation rates inferred from finestructure parameterizations and microstructure-derived estimates suggests a significant departure from wave-wave interaction physics in the near-field of wave generation sites. |
format |
Article in Journal/Newspaper |
author |
Sheen, K.L. Brearley, J. A. Naveira Garabato, A.C. Waterman, S. Smeed, D.A. Ledwell, J.R. Meredith, M.P. St. Laurent, L. Thurnherr, A.M. Toole, J.M. Watson, A.J. |
spellingShingle |
Sheen, K.L. Brearley, J. A. Naveira Garabato, A.C. Waterman, S. Smeed, D.A. Ledwell, J.R. Meredith, M.P. St. Laurent, L. Thurnherr, A.M. Toole, J.M. Watson, A.J. Rates and mechanisms of turbulent dissipation and mixing in the Southern Ocean: Results from the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) |
author_facet |
Sheen, K.L. Brearley, J. A. Naveira Garabato, A.C. Waterman, S. Smeed, D.A. Ledwell, J.R. Meredith, M.P. St. Laurent, L. Thurnherr, A.M. Toole, J.M. Watson, A.J. |
author_sort |
Sheen, K.L. |
title |
Rates and mechanisms of turbulent dissipation and mixing in the Southern Ocean: Results from the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) |
title_short |
Rates and mechanisms of turbulent dissipation and mixing in the Southern Ocean: Results from the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) |
title_full |
Rates and mechanisms of turbulent dissipation and mixing in the Southern Ocean: Results from the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) |
title_fullStr |
Rates and mechanisms of turbulent dissipation and mixing in the Southern Ocean: Results from the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) |
title_full_unstemmed |
Rates and mechanisms of turbulent dissipation and mixing in the Southern Ocean: Results from the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES) |
title_sort |
rates and mechanisms of turbulent dissipation and mixing in the southern ocean: results from the diapycnal and isopycnal mixing experiment in the southern ocean (dimes) |
publishDate |
2013 |
url |
https://eprints.soton.ac.uk/352457/ https://eprints.soton.ac.uk/352457/1/jgrc20217_Sheen.pdf |
geographic |
Antarctic Pacific Scotia Sea Southern Ocean The Antarctic |
geographic_facet |
Antarctic Pacific Scotia Sea Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Scotia Sea Southern Ocean |
genre_facet |
Antarc* Antarctic Scotia Sea Southern Ocean |
op_relation |
https://eprints.soton.ac.uk/352457/1/jgrc20217_Sheen.pdf Sheen, K.L., Brearley, J. A., Naveira Garabato, A.C., Waterman, S., Smeed, D.A., Ledwell, J.R., Meredith, M.P., St. Laurent, L., Thurnherr, A.M., Toole, J.M. and Watson, A.J. (2013) Rates and mechanisms of turbulent dissipation and mixing in the Southern Ocean: Results from the Diapycnal and Isopycnal Mixing Experiment in the Southern Ocean (DIMES). Journal of Geophysical Research: Oceans, 118 (6), 2774-2792. (doi:10.1002/jgrc.20217 <http://dx.doi.org/10.1002/jgrc.20217>). |
op_doi |
https://doi.org/10.1002/jgrc.20217 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
118 |
container_issue |
6 |
container_start_page |
2774 |
op_container_end_page |
2792 |
_version_ |
1775351473264132096 |