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Sensitivity of Arctic Sea ice in Rossby Centre numerical models 
Sensitivity of Arctic Sea ice in Rossby Centre numerical models 
Ralf Doscher, H.E. Markus Meier and Klaus Wyser 
Swedish Meteorological and Hydrological Institute (SMHI) / Rossby Centre 
E-mail: ralf.doescher@smhi.se 
Abstract 
The Rossby Centre modelling system (RCO for the ocean, RCA for the atmosphere and RCAO 
for the coupled setup) is applied in a wider arctic domain. Validation and sensitivity runs are 
carried out based on ERA-40 forcing. 
RCAO and its component models have earlier been successfully applied in a Baltic Sea 
domain. Application of the very same model in the Arctic reveals a tendency towards too much 
sea ice. 
Sea ice extent and concentration serves as a sensitive integral measure of 
(1) the models capability to respresent relevant processes and 
(2) the influence of initial conditions. 
Process formulations such as atmospheric radiation, reflection at the ice surface (albedo), sea 
ice parametersand, the sea ice-atmosphere coupling algorithm and the atlantic oceanic 
boundary condition are tested for their influences. 
A long-term goal for the model development are more robust, physically based and thus more 
universal model formulations which hold for many application domains.