Sensitivity of the simulated Asian summer monsoon to parameterized physical processes

A study of the sensitivity of the simulated Asian summer monsoon to changes in general circulation model formulation is reported. The baseline version of the model fails to realistically simulate the precipitation, wind, and temperature fields. In one experiment the stratiform cloud parameterization was changed from a simple large-scale saturation Scheme to a scheme that p rognostically determines cloud water, cloud ice, and rain. In a second expe riment a parameter that relates the cumulus mass flux to the cumulus kineti c energy was altered so as to increase the convective adjustment time. Thes e changes in the stratiform and cumuliform cloud parameterizations signific antly improve the simulations of the precipitation and upper level wind fie lds, respectively.