Impacts of modifying unresolved cloud structure for radiative transfer in the CCCma GCM

Using a global climate model (GCM) developed at the Canadian Centre for Climate Modelling and Analysis (CCCma) we examine the impact on this GCM of different assumptions about unresolved cloud structure used in the radiative transfer model. Two assumptions will be used to describe unresolved clouds, in one experiment clouds will be assumed to be horizontally homogeneous and follow the maximum-overlap vertical overlap rule and in the second experiment clouds will be assumed horizontally inhomogeneous and use decorrelation lengths to describe overlap.