Atmospheric drag coefficients over sea ice–validation of a parameterisation concept

Abstract

The concept of drag partitioning to parameterise the surface roughness of sea ice is validatedusing topography data of regions with high sea ice concentrations. The parameterised drag iscompared to measurements obtained by aircraft and ship. The form drag can well be expressedas a function of mean ridge heights and spacings averaged over flight legs of 12 km, if animproved approximation for the coefficient of resistance of a single ridge is used. We find agood agreement between the parameterised and observed drag coefficients. The highest sea iceroughness was encountered close to coastal regions and the lowest in the central Arctic.