A 3D-CTM with detailed online PSC-microphysics: analysis of the Antarctic winter 2003 by comparison with satellite observations

[摘要] We present the first detailed microphysical simulations which are performedonline within the framework of a global 3-D chemical transport model (CTM)with full chemistry. The model describes the formation and evolution of fourtypes of polar stratospheric cloud (PSC) particles. Aerosol freezing andother relevant microphysical processes are treated in a full explicit way.Each particle type is described by a binned size distribution for the numberdensity and chemical composition. This set-up allows for an accuratetreatment of sedimentation and for detailed calculation of surface areadensities and optical properties. Simulations are presented for the Antarcticwinter of 2003 and comparisons are made to a diverse set of satelliteobservations (optical and chemical measurements of POAM III and MIPAS) toillustrate the capabilities of the model. This study shows that a combinedresolution approach where microphysical processes are simulated incoarse-grained conditions gives good results for PSC formation and itslarge-scale effect on the chemical environment through processes such asdenitrification, dehydration and ozone loss.

[学科分类] 大气科学