Modification of turbulent dissipation rates by a deep Southern Ocean eddy
Modification of turbulent dissipation rates by a deep Southern Ocean eddy
The impact of a mesoscale eddy on the magnitude and spatial distribution of diapycnal ocean mixing is investigated using a set of hydrographic and microstructure measurements collected in the Southern Ocean. These data sampled a baroclinic, mid-depth eddy formed during the disintegration of a deep boundary current. Turbulent dissipation is suppressed within the eddy, but is elevated by up to an order of magnitude along the upper and lower eddy boundaries. A ray-tracing approximation is employed asa heuristic device to elucidate how the internal wave field evolves in the ambient velocity and stratification conditions accompanying the eddy. These calculations are consistent with the observations, suggesting reflection of internal wave energy from the eddy center and enhanced breaking through critical layer processes along the eddy boundaries. These results have important implications for understanding where and how internal wave energy is dissipated in the presence of energetic deep geostrophic flows.
mixing, eddy, turbulent dissipation, internal waves, southern ocean, ray tracing
3450-3457
Sheen, K.L.
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Brearley, J.A.
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Naveira Garabato, A.C.
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Smeed, D.A.
79eece5a-c870-47f9-bba0-0a4ef0369490
St. Laurent, L.
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Meredith, M.P.
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Thurnherr, A.M.
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Waterman, S.N.
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16 May 2015
Sheen, K.L.
11fc9ce4-1a9a-4925-ae04-816e5e8660ae
Brearley, J.A.
91ab83c7-8d07-4b93-acbf-16ee4a6cdfe5
Naveira Garabato, A.C.
97c0e923-f076-4b38-b89b-938e11cea7a6
Smeed, D.A.
79eece5a-c870-47f9-bba0-0a4ef0369490
St. Laurent, L.
745fc400-a419-4bce-859b-89e63b0cd80d
Meredith, M.P.
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Thurnherr, A.M.
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Waterman, S.N.
e1bb793b-91e2-49a8-bfba-00ddb446ab65
Sheen, K.L., Brearley, J.A., Naveira Garabato, A.C., Smeed, D.A., St. Laurent, L., Meredith, M.P., Thurnherr, A.M. and Waterman, S.N.
(2015)
Modification of turbulent dissipation rates by a deep Southern Ocean eddy.
Geophysical Research Letters, 42 (9), .
(doi:10.1002/2015GL063216).
Abstract
The impact of a mesoscale eddy on the magnitude and spatial distribution of diapycnal ocean mixing is investigated using a set of hydrographic and microstructure measurements collected in the Southern Ocean. These data sampled a baroclinic, mid-depth eddy formed during the disintegration of a deep boundary current. Turbulent dissipation is suppressed within the eddy, but is elevated by up to an order of magnitude along the upper and lower eddy boundaries. A ray-tracing approximation is employed asa heuristic device to elucidate how the internal wave field evolves in the ambient velocity and stratification conditions accompanying the eddy. These calculations are consistent with the observations, suggesting reflection of internal wave energy from the eddy center and enhanced breaking through critical layer processes along the eddy boundaries. These results have important implications for understanding where and how internal wave energy is dissipated in the presence of energetic deep geostrophic flows.
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Accepted/In Press date: April 2015
Published date: 16 May 2015
Keywords:
mixing, eddy, turbulent dissipation, internal waves, southern ocean, ray tracing
Organisations:
Physical Oceanography, Marine Physics and Ocean Climate
Identifiers
Local EPrints ID: 376616
URI: http://eprints.soton.ac.uk/id/eprint/376616
ISSN: 0094-8276
PURE UUID: 7ee5dea0-7442-4257-a519-7bd20b52e8a1
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Date deposited: 29 Apr 2015 08:35
Last modified: 15 Mar 2024 03:24
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Contributors
Author:
K.L. Sheen
Author:
J.A. Brearley
Author:
D.A. Smeed
Author:
L. St. Laurent
Author:
M.P. Meredith
Author:
A.M. Thurnherr
Author:
S.N. Waterman
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