Articles | Volume 4, issue 2
https://doi.org/10.5194/tc-4-147-2010
https://doi.org/10.5194/tc-4-147-2010
Research article
 | 
28 Apr 2010
Research article |  | 28 Apr 2010

Polynyas in a dynamic-thermodynamic sea-ice model

E. Ö. Ólason and I. Harms

Abstract. 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. The two additional rheologies tested give nearly identical results whereas the two new-ice thickness parametrisations tested give widely different results. Based on our results we argue for using the new-ice thickness parametrisation of Hibler (1979). We also implement a new parametrisation for the parameter h0 from Hibler's scheme, based on ideas from a collection depth parametrisation for flux polynya models.