ACP Atmospheric Chemistry and Physics ACP 1680-7324 Copernicus GmbH Göttingen, Germany 10.5194/acp-10-7907-2010 EUCAARI ion spectrometer measurements at 12 European sites – analysis of new particle formation events Manninen H. E. 1 Nieminen T. 1 Asmi E. 2 Gagné S. 1 Häkkinen S. 1 Lehtipalo K. 1 Aalto P. 1 Vana M. 1 3 Mirme A. 3 Mirme S. 3 Hõrrak U. 3 Plass-Dülmer C. 4 Stange G. 4 Kiss G. 5 Hoffer A. 5 Törő N. 5 Moerman M. 6 Henzing B. 6 de Leeuw G. 1 2 6 Brinkenberg M. 7 Kouvarakis G. N. 8 Bougiatioti A. 8 Mihalopoulos N. 8 O'Dowd C. 9 Ceburnis D. 9 Arneth A. 10 Svenningsson B. 11 Swietlicki E. 11 Tarozzi L. 12 Decesari S. 12 Facchini M. C. 12 Birmili W. 13 Sonntag A. 13 Wiedensohler A. 13 Boulon J. 14 Sellegri K. 14 Laj P. 15 Gysel M. 16 Bukowiecki N. 16 Weingartner E. 16 Wehrle G. 16 Laaksonen A. 2 17 Hamed A. 17 Joutsensaari J. 17 Petäjä T. 1 Kerminen V.-M. 1 2 Kulmala M. 1 11 18 Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland Finnish Meteorological Institute, Research and Development, P.O. Box 503, 00101 Helsinki, Finland Institute of Physics, University of Tartu, Ülikooli 18, 50090 Tartu, Estonia Hohenpeissenberg Meteorological Observatory, German Meteorological Service, 82383 Hohenpeissenberg, Germany Air Chemistry Group of Hungarian Academy of Sciences, University of Pannonia, P.O. Box 158, 8201 Veszprém, Hungary Environment, Health and Savety, P.O. Box 80015, 3508 TA Utrecht, Netherlands Organisation for Applied Scientific Research TNO, The Netherlands Royal Netherlands Meteorological Institute KNMI, Regional Climate Division, P.O. Box 201, 3730 AE De Bilt, The Netherlands Environmental Chemical Processes Laboratory, Department of Chemistry, University of Crete, P.O. Box 2208, 71003, Heraklion, Greece School of Physics and Centre for Climate & Air Pollution Studies, Environmental Change Institute, National University of Ireland, Galway, Galway, Ireland Lund University, Dept. Physical Geography and Ecosystem Analysis, Sölvegatan 12, 22362 Lund, Sweden Department of Physics, Lund University, P.O. Box 118, 221 00, Sweden Institute of Atmospheric Sciences and Climate, ISAC – CNR, Consiglio Nazionale delle Ricerche, Bologna, Italy Leibniz Institute for Tropospheric Research, Permoserstrasse 15, 04303 Leipzig, Germany Laboratoire de Météorologie Physique, Blaise Pascal Univ., 63000, Clermont-Ferrand, France Laboratoire de Glaciologie et Géophysique de l'Environnement, Université de Grenoble 1 – CNRS, Grenoble, France Paul Scherrer Institut, Laboratory of Atmospheric Chemistry, 5232 Villigen PSI, Switzerland Department of Physics and Mathematics, University of Eastern Finland, Kuopio, 70211, Finland Department of Applied Environmental Science (ITM), Stockholm University, Svante Arrheniusväg 8, 106 91 Stockholm, Sweden 25 08 2010 10 16 7907 7927 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/10/7907/2010/acp-10-7907-2010.html The full text article is available as a PDF file from http://www.atmos-chem-phys.net/10/7907/2010/acp-10-7907-2010.pdf

We present comprehensive results on continuous atmospheric cluster and particle measurements in the size range ~1–42 nm within the European Integrated project on Aerosol Cloud Climate and Air Quality interactions (EUCAARI) project. We focused on characterizing the spatial and temporal variation of new particle formation events and relevant particle formation parameters across Europe. Different types of air ion and cluster mobility spectrometers were deployed at 12 field sites across Europe from March 2008 to May 2009. The measurements were conducted in a wide variety of environments, including coastal and continental locations as well as sites at different altitudes (both in the boundary layer and the free troposphere). New particle formation events were detected at all of the 12 field sites during the year-long measurement period. From the data, nucleation and growth rates of newly formed particles were determined for each environment. In a case of parallel ion and neutral cluster measurements, we could also estimate the relative contribution of ion-induced and neutral nucleation to the total particle formation. The formation rates of charged particles at 2 nm accounted for 1–30% of the corresponding total particle formation rates. As a significant new result, we found out that the total particle formation rate varied much more between the different sites than the formation rate of charged particles. This work presents, so far, the most comprehensive effort to experimentally characterize nucleation and growth of atmospheric molecular clusters and nanoparticles at ground-based observation sites on a continental scale.

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