References

ACP

Atmospheric Chemistry and Physics

ACP

1680-7324

Copernicus GmbH

Göttingen, Germany

10.5194/acp-8-1985-2008

Technical note: Analytical formulae for the critical supersaturations and droplet diameters of CCN containing insoluble material

Kokkola

¹ Vesterinen

³ Anttila

² Laaksonen

² ³ Lehtinen

K. E. J.

¹ ³

Finnish Meteorological Institute, Kuopio Unit, P.O.Box 1627, FI-70211 Kuopio, Finland

Finnish Meteorological Institute, P.O.Box 503, FI-00101 Helsinki, Finland

Department of Physics, University of Kuopio, P.O.Box 1672, FI-70211 Kuopio, Finland

08 04 2008

8 7 1985 1988

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In this paper, we consider the cloud drop activation of aerosol particles consisting of water soluble material and an insoluble core. Based on the Köhler theory, we derive analytical equations for the critical diameters and supersaturations of such particles. We demonstrate the use of the equations by comparing the critical supersaturations of particles composed of ammonium sulfate and insoluble substances with those of model organic particles with varying molecular sizes.

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