Forcing of the overturning circulation across a circumpolar channel by internal wave breaking
The hypothesis that the impingement of mesoscale eddy flows on small-scale topography regulates diapycnal mixing and meridional overturning across the deep Southern Ocean is assessed in an idealised model. The model simulates an eddying circumpolar current coupled to a double-celled meridional overt...
| Published in: | Journal of Geophysical Research: Oceans |
|---|---|
| Main Authors: | , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
2016
|
| Subjects: | |
| Online Access: | http://nora.nerc.ac.uk/id/eprint/513884/ https://nora.nerc.ac.uk/id/eprint/513884/7/jgrc21824.pdf https://nora.nerc.ac.uk/id/eprint/513884/1/jgrc21824.pdf https://doi.org/10.1002/2015JC011597 |
| Summary: | The hypothesis that the impingement of mesoscale eddy flows on small-scale topography regulates diapycnal mixing and meridional overturning across the deep Southern Ocean is assessed in an idealised model. The model simulates an eddying circumpolar current coupled to a double-celled meridional overturning with properties broadly resembling those of the Southern Ocean circulation, and represents lee wave-induced diapycnal mixing using an online formulation grounded on wave radiation theory. The diapycnal mixing generated by the simulated eddy field is found to play a major role in sustaining the lower overturning cell in the model, and to underpin a significant sensitivity of this cell to wind forcing. The vertical structure of lower overturning is set by mesoscale eddies, which propagate the effects of near-bottom diapycnal mixing by displacing isopycnals vertically. |
|---|