CESM2/CARMA Cloud and CARMA Aerosol Model Descriptions

The Community Aerosol and Radiation Model for Atmospheres (CARMA) is a sectional microphysical model widely used to understand the formation of aerosols and clouds. This paper is an updated description of the CARMA model algorithms since Toon et al 1988, with examples from the newly developed CARMA Cloud model. This paper describes the general algorithms and solvers for nucleation, condensation/evaporation, coagulation, and sedimentation shared among all CARMA aerosols and clouds models; specific microphysical processes needed for water droplet and ice; how the CARMA Cloud is set up and how it interacts with other processes inside the Community Earth System Model.