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Abstract

This study investigated seasonal variations of new particle formation (NPF) events in Beijing by using observations of particle size distributions and chemical compositions of aerosols and numerical model simulations. The authors found no apparent growth of new particles in winter whereas the growth of new particles to CCN size (50 or 75 nm) was often observed in summer. The three patterns of NPF events during the summertime were discussed in terms of secondary aerosol formation, evaporation of semivolatile species, and spatial heterogeneity of NPF events. The scope of this manuscript