ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-12-12037-2012 Cloud condensation nuclei production associated with atmospheric nucleation: a synthesis based on existing literature and new results Kerminen V.-M. 1 Paramonov M. 1 Anttila T. 2 Riipinen I. 3 Fountoukis C. 4 Korhonen H. 5 Asmi E. 2 Laakso L. 2 Lihavainen H. 2 Swietlicki E. 6 Svenningsson B. 6 Asmi A. 1 Pandis S. N. 4 Kulmala M. 1 Petäjä T. 1 Department of Physics, University of Helsinki, 00014 Helsinki, Finland Finnish Meteorological Institute, Research and Development, 00101 Helsinki, Finland Department of Applied Environmental Science & Bert Bolin Centre for Climate Research, Stockholm University, 11418, Stockholm, Sweden Institute of Chemical Engineering Sciences, Foundation for Research and Technology Hellas (ICEHT/FORTH), Patras, Greece Finnish Meteorological Institute, Kuopio Unit, P.O. Box 1627, 70211 Kuopio, Finland Division of Nuclear Physics, Lund University, P.O. Box 118, 22100 Lund, Sweden 19 12 2012 12 24 12037 12059 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys.net/12/12037/2012/acp-12-12037-2012.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/12/12037/2012/acp-12-12037-2012.pdf

This paper synthesizes the available scientific information connecting atmospheric nucleation with subsequent cloud condensation nuclei (CCN) formation. We review both observations and model studies related to this topic, and discuss the potential climatic implications. We conclude that CCN production associated with atmospheric nucleation is both frequent and widespread phenomenon in many types of continental boundary layers, and probably also over a large fraction of the free troposphere. The contribution of nucleation to the global CCN budget spans a relatively large uncertainty range, which, together with our poor understanding of aerosol-cloud interactions, results in major uncertainties in the radiative forcing by atmospheric aerosols. In order to better quantify the role of atmospheric nucleation in CCN formation and Earth System behavior, more information is needed on (i) the factors controlling atmospheric CCN production and (ii) the properties of both primary and secondary CCN and their interconnections. In future investigations, more emphasis should be put on combining field measurements with regional and large-scale model studies.

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