| 100 | 100 | Two-moment cloud microphysics according to Seifert and Beheng (2006), Khairoutdinov and Kogan (2000), Khvorostyanov and Curry (2006) and Morrison and Grabowski (2007). The 'morrison'-scheme can be understood as an extension of the implemented 'seifert_beheng'-scheme. In comparison to the 'seifert_beheng'-scheme there are three main differences. First, instead of saturation adjustment the diffusional growth is parametrized while calculating condensation/evaporation rates explicitly. However, for a appropriate usage of this scheme the time-step must smaller than the diffusional growth relaxation time. Usually, this is in the order of 1-2 seconds. Second, the activation is considered with a simple Twomey activation-scheme. For this also Koehler-theory can take into account with the parameter [#curvature_solution_effects_bulk curvature_solution_effects_bulk] = T. The background aerosol concentration, which also determines the maximum number of activated cloud droplets, can be prescribed with [#na_init na_init]. Thirdly, the number concentration of cloud droplets (nc) and the cloud water mixing ratio (qc) are prognostic quantities. This allows a change of the cloud droplet number which is also considered for all microphysical processes. \\\\ |
