SIMULATION OF CLOUD MICROPHYSICAL AND CHEMICAL PROCESSES USING A MULTICOMPONENT FRAMEWORK .1. DESCRIPTION OF THE MICROPHYSICAL MODEL

A detailed microphysical and chemical cloud model has been developed to investigate the redistribution of atmospheric trace substances through cloud processes. A multicomponent categorization scheme is used to group cloud particles into different bins according to their various properties. Cloud drops are categorized simultaneously and independently in both their water mass and solute mass components. Ice phase particles are additionally categorized according to their ''shapes,'' special effort having been paid to the parameterization of their growth and habit changes. The hybrid bin method used conserves the mass and number of particles while at the same time performing fast and accurate calculations for transferring various properties between categories within the multicomponent framework. With a minimum of parameterization, this model is capable of simulating detailed microphysical and chemical processes that occur during cloud and precipitation formation.