Forschung im HLRN-Verbund 2011

53Figure 1: Four snapshots of bottom passive tracer concentration at spring tides with 6h intervals (clockwise). Thepassive tracer was injected into the high salinity shelf water (HSSW), the source of the overflow water.It is restored to one inside HSSW over the inner shelf and is set to zero anywhere else at the beginningof the simulation. Reduction of concentration along the plume path is due to mixing of HSSW with ambientwarm water. The black arrows indicate the near bottom velocity. These snapshots show the tidaladvection effect on the overflows.bottom water formation because of energetic mixingover the upper slope. Compared to a simulationwithout tidal forcing, tides (with the major K1 andO1 constituents) increase the outflow rate over thecontinental slope off Cape Adare by about 70%. Aset of sensitivity experiments show that the rate ofbottom water production is not a monotonic functionof the tidal currents amplitude. Tidal forcingwith intermediate strength leads to the most efficientbottom water formation.FESOM simulations require a massively parallelenvironment and would hardly be possible withoutthe support from HLRN. Our future work will needlarger meshes and more computational resources.We hope that it will also benefit from the HLRN assistance.More Information1. Wang, Q., S. Danilov, and J. Schröter (2008),Finite element ocean circulation model basedon triangular prismatic elements, with applicationin studying the effect of vertical discretization,J. Geophys. Res., 113, C05015,doi:10.1029/2007JC004482.2. Timmermann, R., S. Danilov, J. Schröter, C.Böning, D. Sidorenko, and K. Rollenhagen(2009), Ocean circulation and sea ice distributionin a finite element global sea ice-oceanmodel, Ocean Modell. 27, 114-129.3. Sidorenko, D., Q. Wang, S. Danilov, andJ. Schröter (2010), FESOM under CoordinatedOcean-ice Reference Experiment forcing,Ocean Dynamics, submitted.4. Wang, Q., S. Danilov, H. H. Hellmer, and J.Schröter (2010), Overflow dynamics and bottomwater formation in the western Ross Sea: Influenceof tides, J. Geophys. Res., 115, C10054,doi:10.1029/2010JC006189.FundingHelmholtz AssociationGeowissenschaften