Formation of sulphuric acid aerosols and cloud condensation nuclei : An expression for significant nucleation and model comparison

• Published in: Journal of aerosol science Vol. 30; no. 8; pp. 1079 - 1094
• Main Authors: PIRJOLA, L, KULMALA, M, WILCK, M, BISCHOFF, A, STRATMANN, F, OTTO, E
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Science 01.09.1999
• Subjects: Applied sciences; Atmospheric pollution; Chemistry; Colloidal gels. Colloidal sols; Colloidal state and disperse state; Exact sciences and technology; General and physical chemistry; Pollution; Prevention and purification methods; Aerosols; Atmospheric condition; Nucleation; Condensation nucleus; Modeling; Sulfuric acid
• ISSN: 0021-8502; 1879-1964
• DOI: 10.1016/S0021-8502(98)00776-9

The evolution of sulfuric acid aerosols is examined mathematically, and the formation of these new particles is simulated using three different aerosol dynamic models: a monodisperse model, a sectional model, and a moment model. Each is detailed. The model results are compared to determine the atmospheric conditions when significant aerosol formation and cloud condensation nuclei formation take place. A new expression for these conditions is then derived, which holds that the threshold of the particle and cloud condensation nuclei formation can be obtained using the ratio between the chemical reactions and the condensational sink for the condensable vapor. This ratio is a function of temperature, relative humidity, and the properties of the pre-existing aerosol. Of the three models evaluated, the sectional model is shown to be the most accurate.