A model for particle formation and growth in the atmosphere with molecular resolution in size

[摘要] The formation and growth of atmospheric aerosol particles is considered using an exactdiscrete method with molecular resolution in size space. The method is immune to numericaldiffusion problems that are a nuisance for typical simulation methods using a sectionalrepresentation for the particle size distribution. For condensational growth, a slightmodification is proposed for the Fuchs-Sutugin expression, which improves the prediction ofthe growth rate of nano-sized particles by as much as a factor of two. The presented method isapplied to particle formation in a Finnish Boreal forest and is shown to capture the essentialfeatures of the dynamics quite nicely. Furthermore, it is shown that the growth of the particlesis roughly linear, which means that the amount of condensable vapour is constant (of theorder 10¹³ 1/m³).

[学科分类] 大气科学