Essential Site Maintenance: Authorea-powered sites will be updated circa 15:00-17:00 Eastern on Tuesday 5 November.
There should be no interruption to normal services, but please contact us at [email protected] in case you face any issues.

loading page

Impact of Isopycnal Mixing on Southern Ocean Overturning Geometry
  • Nicole Neumann,
  • C Spencer Jones
Nicole Neumann
Texas A&M University

Corresponding Author:[email protected]

Author Profile
C Spencer Jones
Texas A&M University
Author Profile

Abstract

In coarse resolution ocean models, eddy diffusive effects are parameterized with an isopycnal mixing coefficient, which controls mixing strength along isopycnals. Both wind and isopycnal mixing affect surface temperature and salinity in the Southern Ocean, influencing the buoyancy of waters near Antarctica. Using an idealized MITgcm basin-channel model, we varied both Southern Ocean wind stress and the isopycnal mixing coefficient. We found that strong Southern Ocean winds make the abyssal cell’s strength insensitive to isopycnal mixing, while weak winds only allow AABW formation if the mixing coefficient exceeds 500 $m^2/s$. Higher isopycnal mixing brings warmer, saltier water to the surface of the Southern Ocean, where it cools, becomes denser, and forms AABW. Increasing the isopycnal mixing coefficient increases the latitudinal span of negative surface buoyancy flux close to Antarctica. Hence, changing the isopycnal mixing is likely to have an impact on the water properties of AABW.
05 Sep 2024Submitted to ESS Open Archive
09 Sep 2024Published in ESS Open Archive