Ocean Circulation and Climate Dynamics

SVDEP

Contact: Willi Rath und Richard J. Greatbatch

Influence of the ocean surface velocity dependence of the surface wind stress on the dynamics of the Southern Ocean

The figure shows time averaged wind power input (W/m2) for the five days preceeding May 10, 2001. It clearly reveals the enormous range of temporal and spatial scales contributing to the problem. The large wavy structure shows the location of three fast moving storms. The small filaments show the various
  • The project aims at understanding the impact of neglecting/including the ocean surface velocity dependence of the surface wind stress on the circulation of the Southern Ocean using a realistic eddying model. 
  • Typical wind velocities do by far exceed the typical velocities of the surface ocean circulation. Hence, the contribution of the oceanic surface velocity to the wind stress is often neglected. The impact of this simplification is not straightforward. Earlier studies suggest that including the ocean surface velocity dependence leads to a reduction of the work done by the wind, and a "damping" of mesoscale eddies, which leads to reduction of Eddy Kinetic Energy by more than 10 percent. However, the impact of this eddy damping on the meridional overturning circulation and, in turn, on the stratification and on vertically integrated transport is still under debate.