Widespread Intense Turbulent Mixing in the Southern Ocean
Alberto C. Naveira Garabato,1*
Kurt L. Polzin,2
Brian A. King,3
Karen J. Heywood,1
Martin Visbeck4
Observations of internal wave velocity fluctuations show that
enhanced turbulent mixing over rough topography in the Southern
Ocean is remarkably intense and widespread. Mixing rates exceeding
background values by a factor of 10 to 1000 are common above
complex bathymetry over a distance of 2000 to 3000 kilometers
at depths greater than 500 to 1000 meters. This suggests that
turbulent mixing in the Southern Ocean may contribute crucially
to driving the upward transport of water closing the ocean's
meridional overturning circulation, and thus needs to be represented
in numerical simulations of the global ocean circulation and
the spreading of biogeochemical tracers.
2 Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
3 Southampton Oceanography Centre, Southampton SO14 3ZH, UK.
4 Lamont-Doherty Earth Observatory, Palisades, NY 10964–8000, USA.
* To whom correspondence should be addressed. E-mail: a.naveira-garabato{at}uea.ac.uk
