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Can chemical effects on cloud droplet number rival the first indirect effect?

Nenes, Athanasios and Charlson, Robert J. and Facchini, M. Cristina and Kulmala, Markku and Laaksonen, Ari and Seinfeld, John H. (2002) Can chemical effects on cloud droplet number rival the first indirect effect? Geophysical Research Letters, 29 (17). Art. No. 1848. ISSN 0094-8276. doi:10.1029/2002GL015295.

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An increase in cloud droplet number concentration resulting from an increase in ambient aerosol (and subsequent albedo increase) is typically identified as the first indirect (or “Twomey”) climatic effect of aerosols [Twomey, 1974]. A key question is whether chemical effects (dissolution of soluble gases and slightly soluble substances, surface tension depression by organic substances and accommodation coefficient changes) could potentially rival changes in droplet number from changes in aerosol number concentration. We assess the sensitivity of cloud droplet number concentration to such chemical factors, using a cloud parcel model. We find that numerous conditions exist, for which chemical influences on cloud droplet activation can indeed rival the Twomey effect.

Item Type:Article
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URLURL TypeDescription
Nenes, Athanasios0000-0003-3873-9970
Seinfeld, John H.0000-0003-1344-4068
Additional Information:Copyright 2002 by the American Geophysical Union. Received 9 April 2002; revised 2 July 2002; accepted 9 July 2002; published 13 September 2002. A. Nenes and J. H. Seinfeld were supported by U.S. Office of Naval Research grant N00014-96-1-0119. We would also like to thank P. Y.Chuang and J.Snider for their important comments during the review process. Finally, we would like to acknowledge M. Mircea for helpful suggestions during the preparation of the manuscript.
Funding AgencyGrant Number
Office of Naval Research (ONR)N00014-96-1-0119
Issue or Number:17
Classification Code:0305 Atmospheric Composition and Structure: Aerosols and particles (0345, 4801); 0320 Atmospheric Composition and Structure: Cloud physics and chemistry; 0345 Atmospheric Composition and Structure: Pollution—urban and regional (0305)
Record Number:CaltechAUTHORS:20141027-145634392
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Official Citation:Nenes, A., R. J. Charlson, M. C. Facchini, M. Kulmala, A. Laaksonen, and J. H. Seinfeld, Can chemical effects on cloud droplet number rival the first indirect effect? Geophys. Res. Lett., 29(17), 1848, doi:10.1029/2002GL015295, 2002.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:50878
Deposited By: George Porter
Deposited On:27 Oct 2014 22:06
Last Modified:10 Nov 2021 19:02

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