Chemical consequences of the initial diffusional growth of cloud droplets: a clean marine case

C. H. Twohy; P. H. Austin; R. J. Charlson

doi:10.3402/tellusb.v41i1.15047

Chemical consequences of the initial diffusional growth of cloud droplets: a clean marine case

Tellus B: Chemical and Physical Meteorology

Volume 41 (1989): Issue 1

By: C. H. Twohy, P. H. Austin and R. J. Charlson

Open Access

|Jan 1989

Abstract

A simple microphysical cloud parcel model and a simple representation of the background marine aerosol are used to predict the concentrations and compositions of droplets of various sizes near cloud base. The aerosol consists of an externally-mixed ammonium bisulfate accumulation mode and a sea-salt coarse particle mode. The difference in diffusional growth rates between the small and large droplets as well as the differences in composition between the two aerosol modes result in substantial differences in solute concentration and composition with size of droplets in the parcel. The chemistry of individual droplets is not, in general, representative of the “bulk” (volume-weighted mean) cloud water sample. These differences, calculated to occur early in the parcel’s lifetime, should have important consequences for chemical reactions such as aqueous phase sulfate production.

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Articles in this issue

DOI: https://doi.org/10.3402/tellusb.v41i1.15047 | Journal eISSN: 1600-0889

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Language: English

Page range: 51 - 60

Submitted on: Dec 30, 1987

Accepted on: May 17, 1988

Published on: Jan 1, 1989

Published by: Stockholm University Press

In partnership with: Paradigm Publishing Services

© 1989 C. H. Twohy, P. H. Austin, R. J. Charlson, published by Stockholm University Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 41 (1989): Issue 1