Eddy cancellation of the Ekman cell in subtropical gyres
The presence of large-scale Ekman pumping associated with the climatological wind stress curl is the textbook explanation for low biological activity in the subtropical gyres. Using an idealized eddy-resolving model it is shown that Eulerian-mean Ekman pumping may be opposed by an eddy-driven circul...
| Published in: | Journal of Physical Oceanography |
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| Main Authors: | , , |
| Format: | Article in Journal/Newspaper |
| Language: | unknown |
| Published: |
American Meteorological Society
2016
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| Subjects: | |
| Online Access: | https://doi.org/10.1175/JPO-D-16-0097.1 https://ora.ox.ac.uk/objects/uuid:b53bc9b2-c622-46b1-aecf-9ff86411f0f2 |
| Summary: | The presence of large-scale Ekman pumping associated with the climatological wind stress curl is the textbook explanation for low biological activity in the subtropical gyres. Using an idealized eddy-resolving model it is shown that Eulerian-mean Ekman pumping may be opposed by an eddy-driven circulation, analogous to the way in which the atmospheric Ferrel cell and the Southern Ocean Deacon cell are opposed by eddy-driven circulations. Lagrangian particle tracking, potential vorticity fluxes, and depth-density streamfunctions are used to show that, in the model, the rectified effect of eddies acts to largely cancel the Eulerian-mean Ekman downwelling. To distinguish this effect from eddy compensation, it is proposed that the suppression of Eulerian-mean downwelling by eddies be called ``eddy cancellation.'' |
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