Editorial Type:
Article
Article Type:
Research Article

Eddy-Induced Diapycnal Fluxes and Their Role in the Maintenance of the Thermocline

Timour Radko Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts

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John Marshall Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts

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Print Publication:
01 Feb 2004
DOI:
https://doi.org/10.1175/1520-0485(2004)034<0372:EDFATR>2.0.CO;2
Page(s):
372–383
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Abstract

High-resolution numerical experiments are diagnosed to study the integral effects of geostrophic eddy fluxes on the large-scale ocean circulation. Three characteristic large-scale flows are considered: 1) an anticyclonic single gyre, 2) a double gyre, and 3) an unblocked zonal flow, a simple analog of the Antarctic Circumpolar Current. It is found that buoyancy and potential vorticity budgets in the presence of eddies are dominated by a balance between vertical advection into the control volume by Ekman pumping and eddy transfer across the density surfaces achieved by diapycnal eddy fluxes, with small-scale mixing making only a minor contribution. Possible oceanographic implications of the results are discussed.

Corresponding author address: Dr. Timour Radko, Dept. of Earth, Atmospheric, and Planetary Sciences, MIT, Bldg. 54-1517, 77 Massachusetts Avenue, Cambridge, MA 02139. Email: timour@ocean.mit.edu

Abstract

High-resolution numerical experiments are diagnosed to study the integral effects of geostrophic eddy fluxes on the large-scale ocean circulation. Three characteristic large-scale flows are considered: 1) an anticyclonic single gyre, 2) a double gyre, and 3) an unblocked zonal flow, a simple analog of the Antarctic Circumpolar Current. It is found that buoyancy and potential vorticity budgets in the presence of eddies are dominated by a balance between vertical advection into the control volume by Ekman pumping and eddy transfer across the density surfaces achieved by diapycnal eddy fluxes, with small-scale mixing making only a minor contribution. Possible oceanographic implications of the results are discussed.

Corresponding author address: Dr. Timour Radko, Dept. of Earth, Atmospheric, and Planetary Sciences, MIT, Bldg. 54-1517, 77 Massachusetts Avenue, Cambridge, MA 02139. Email: timour@ocean.mit.edu

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