Study of Ice Cloud Formation and Evolution in the Tropical Cloud Belt with a Detailed Microphysical Model

MARSBOX is a recently developed microphysical model for Martian ice clouds based on the state-ofthe-art model for terrestrial Polar Stratospheric Clouds PSCbox [2, 3]. Two types of particles are considered: dust particles and dust coated with ice (ice particles), with, for both, a size-resolved distribution discretized in geometrically increasing size bins. We here run the model with 30 bins. The microphysical processes taken into account are: heterogeneous nucleation of dust particles by surface diffusion of water vapor, and condensation/sublimation of water vapor on/from ice particles. The vertical transport is described by gravitational sedimentation and eddy diffusion. The model has a timestep of 1/10solhr and an internal variable timestep, of minimum 0.1s and maximum 1/10solhr determined by the speed of the microphysical processes.