A Multidimensional Model for Aerosols: Description of Computational Analogs

The numerical algorithms which we use to simulate the advection, diffusion, sedimentation, coagulation and condensational growth of atmospheric aerosols are described. The model can be used in one, two, or three spatial dimensions. We develop the continuity equation in a generalized horizontal and vertical coordinate system which allows the model to be quickly adapted to a wide variety of dynamical models of global or regional scale. Algorithms are developed to treat the various physical processes and the results of simulations are presented which show the strengths and weaknesses of these algorithms. Although our emphasis is on the modeling of aerosols, the work is also applicable to simulations of the transport of gases.