The Cryosphere www.the-cryosphere.net 1994-0416 1994-0424 4 2 2010 10.5194/tc-4-147-2010 http://www.the-cryosphere.net/4/147/2010/ http://www.the-cryosphere.net/4/147/2010/tc-4-147-2010.html http://www.the-cryosphere.net/4/147/2010/tc-4-147-2010.pdf 147 160 2010-04-28 Polynyas in a dynamic-thermodynamic sea-ice model E. Ö. Ólason einar.olason@zmaw.de I. Harms Centre for Marine and Atmospheric Research, Institute of Oceanography, University of Hamburg, Hamburg, Germany The representation of polynyas in viscous-plastic dynamic-thermodynamic sea-ice models is studied in a simplified test domain, in order to give recommendations about parametrisation choices. Bjornsson et al. (2001) validated their dynamic-thermodynamic model against a polynya flux model in a similar setup and we expand on that work here, testing more sea-ice rheologies and new-ice thickness formulations. 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