Community Research and Development Information Service - CORDIS

Abstract

A full scale aerosol dynamical model is used to model formation and growth of H(2)SO(4)-H(2)O particles in the homogeneous gas phase. The model describes the evolution in time of the particle size distribution, allowing the calculation of the detectable fraction of the aerosol (CN) as well as the number of cloud condensation nuclei (CCN) active at various supersaturations. The model is applied to CN and CCN formation in the remote marine environment. Constrained by observed CN concentrations, the model confirms in a rigorous way that nucleation of H(2)SO(4)-H(2)O droplets preferentially occurs at relative humidities betweeen 80 and 98 %. It further predicts that the lifetime of the particles formed by nucleation is more than 4 days when subject only to dry deposition. This is sufficient to make them grow by condensation and coagulation to sizes up to Rp = 0.08 microns, and implies that CCN active at supersaturations as low as 0.5 % can be formed eventually by these in situ gas phase processes.

Additional information

Authors: RAES F, JRC Ispra (IT);VAN DINGENEN R, JRC Ispra (IT)
Bibliographic Reference: Article: Journal of Geophysical Research, Vol. 97 (1992) No. D12, pp. 12901-12912
Follow us on: RSS Facebook Twitter YouTube Managed by the EU Publications Office Top