Articles | Volume 20, issue 2
https://doi.org/10.5194/os-20-601-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/os-20-601-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
19 Apr 2024
Research article |
| 19 Apr 2024
| 19 Apr 2024
The Southern Ocean deep mixing band emerges from a competition between winter buoyancy loss and upper stratification strength
Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
Fabien Roquet
Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden
Jonas Nycander
Department of Meteorology, Stockholm University, Stockholm, Sweden
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Short summary
In winter, heat loss increases density at the surface of the Southern Ocean. This increase in density creates a mixed layer deeper than 250 m only in a narrow deep mixing band (DMB) located around 50° S. North of the DMB, the stratification is too strong to be eroded, so mixed layers are shallower. The density of cold water is almost not impacted by temperature changes. Thus, heat loss does not significantly increase the density south of the DMB, so no deep mixed layers are produced.
In winter, heat loss increases density at the surface of the Southern Ocean. This increase in...
