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The role of ions in new particle formation in the CLOUD chamber

Wagner, Robert and Mai, Huajun and Flagan, Richard C. (2017) The role of ions in new particle formation in the CLOUD chamber. Atmospheric Chemistry and Physics, 17 (24). pp. 15181-15197. ISSN 1680-7316. doi:10.5194/acp-17-15181-2017.

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The formation of secondary particles in the atmosphere accounts for more than half of global cloud condensation nuclei. Experiments at the CERN CLOUD (Cosmics Leaving OUtdoor Droplets) chamber have underlined the importance of ions for new particle formation, but quantifying their effect in the atmosphere remains challenging. By using a novel instrument setup consisting of two nanoparticle counters, one of them equipped with an ion filter, we were able to further investigate the ion-related mechanisms of new particle formation. In autumn 2015, we carried out experiments at CLOUD on four systems of different chemical compositions involving monoterpenes, sulfuric acid, nitrogen oxides, and ammonia. We measured the influence of ions on the nucleation rates under precisely controlled and atmospherically relevant conditions. Our results indicate that ions enhance the nucleation process when the charge is necessary to stabilize newly formed clusters, i.e., in conditions in which neutral clusters are unstable. For charged clusters that were formed by ion-induced nucleation, we were able to measure, for the first time, their progressive neutralization due to recombination with oppositely charged ions. A large fraction of the clusters carried a charge at 1.5 nm diameter. However, depending on particle growth rates and ion concentrations, charged clusters were largely neutralized by ion–ion recombination before they grew to 2.5 nm. At this size, more than 90 % of particles were neutral. In other words, particles may originate from ion-induced nucleation, although they are neutral upon detection at diameters larger than 2.5 nm. Observations at Hyytiälä, Finland, showed lower ion concentrations and a lower contribution of ion-induced nucleation than measured at CLOUD under similar conditions. Although this can be partly explained by the observation that ion-induced fractions decrease towards lower ion concentrations, further investigations are needed to resolve the origin of the discrepancy.

Item Type:Article
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URLURL TypeDescription
Mai, Huajun0000-0002-0616-1986
Flagan, Richard C.0000-0001-5690-770X
Additional Information:© 2017 the Author(s). This work is distributed under the Creative Commons Attribution 4.0 License. Published by Copernicus Publications on behalf of the European Geosciences Union. Received: 08 Jun 2017 – Discussion started: 17 Jul 2017. Revised: 08 Nov 2017 – Accepted: 12 Nov 2017 – Published: 21 Dec 2017. We thank the European Organization for Nuclear Research (CERN) for supporting CLOUD with important technical and financial resources and providing a particle beam from the CERN Proton Synchrotron. We also thank P. Carrie, L.-P. De Menezes, J. Dumollard, K. Ivanova, F. Josa, I. Krasin, R. Kristic, A. Laassiri, O. S. Maksumov, B. Marichy, H. Martinati, S. V. Mizin, R. Sitals, A. Wasem, and M. Wilhelmsson for their contributions to the experiment. This research was supported by the EC Seventh Framework Programme (Marie Curie ITN CLOUD-TRAIN, no. 316662; advanced grant, ATMNUCLE, no. 227463; consolidator grant NANODYNAMITE, no. 616075; starting grant QAPPA, no. 335478; starting grant MOCAPAF, no. 257360; MC-COFUND CERN-COFUND-2012, no. 600377), EC Horizon 2020 (Marie Skłodowska-Curie Individual Fellowships Nano-CAVa, no. 656994; starting grant COALA, no. 638703), German Federal Ministry of Education and Research (nos. 01LK1222A and 01LK0902A), Presidium of the Russian Academy of Sciences and Russian Foundation for Basic Research (grants 08-02-91006-CERN and 12-02-91522-CERN), US Department of Energy (no. DE-SC0014469), Swiss National Science Foundation (206620_141278, 200020_135307, 200021_140663, 206021_144947/1), Austrian Science Fund (J3198-N21, L593, P19546), Portuguese Foundation for Science and Technology (CERN/FP/116387/2010), Swedish Research Council (2011-5120), US National Science Foundation (AGS1136479, AGS1447056, AGC1439551, CHE1012293), Natural Environment Research Council (NE/J024252/1, NE/K015966/1), Royal Society (Wolfson Merit Award), Dreyfus Award (EP-11-117), European Funds for Regional Economic Development (Labex-Cappa grant, ANR-11-LABX-0005-01), Nessling Foundation, Finnish Funding Agency for Technology and Innovation, Väisälä Foundation, Caltech Environmental Science and Engineering grant (Davidow Foundation), French National Research Agency, Nord-Pas de Calais, and the Academy of Finland (nos. 299574, 1118615, 135054, 133872, 251427, 139656, 139995, 141451, 137749, 141217, 138951).
Funding AgencyGrant Number
Marie Curie Fellowship316662
European Research Council (ERC)227463
European Research Council (ERC)616075
European Research Council (ERC)335478
European Research Council (ERC)257360
Marie Curie Fellowship600377
Marie Curie Fellowship656994
Marie Curie Fellowship638703
Bundesministerium für Bildung und Forschung (BMBF)01LK1222A
Bundesministerium für Bildung und Forschung (BMBF)01LK0902A
Russian Foundation for Basic Research08-02-91006-CERN
Russian Foundation for Basic Research12-02-91522-CERN
Department of Energy (DOE)DE-SC0014469
Swiss National Science Foundation (SNSF)206620_141278
Swiss National Science Foundation (SNSF)200020_135307
Swiss National Science Foundation (SNSF)200021_140663
Swiss National Science Foundation (SNSF)206021_144947/1
FWF Der WissenschaftsfondsJ3198-N21
FWF Der WissenschaftsfondsL593
FWF Der WissenschaftsfondsP19546
Fundação para a Ciência e a Tecnologia (FCT)CERN/FP/116387/2010
Swedish Research Council2011-5120
Natural Environment Research Council (NERC)NE/J024252/1
Natural Environment Research Council (NERC)NE/K015966/1
Camille and Henry Dreyfus FoundationEP-11-117
Agence Nationale pour la Recherche (ANR)ANR-11-LABX-0005-01
Nessling FoundationUNSPECIFIED
Finnish Funding Agency for Technology and InnovationUNSPECIFIED
Väisälä FoundationUNSPECIFIED
Davidow FoundationUNSPECIFIED
French National Research AgencyUNSPECIFIED
Nord-Pas de CalaisUNSPECIFIED
Academy of Finland299574
Academy of Finland1118615
Academy of Finland135054
Academy of Finland133872
Academy of Finland251427
Academy of Finland139656
Academy of Finland139995
Academy of Finland141451
Academy of Finland137749
Academy of Finland141217
Academy of Finland138951
Issue or Number:24
Record Number:CaltechAUTHORS:20180105-133848781
Persistent URL:
Official Citation:Wagner, R., Yan, C., Lehtipalo, K., Duplissy, J., Nieminen, T., Kangasluoma, J., Ahonen, L. R., Dada, L., Kontkanen, J., Manninen, H. E., Dias, A., Amorim, A., Bauer, P. S., Bergen, A., Bernhammer, A.-K., Bianchi, F., Brilke, S., Mazon, S. B., Chen, X., Draper, D. C., Fischer, L., Frege, C., Fuchs, C., Garmash, O., Gordon, H., Hakala, J., Heikkinen, L., Heinritzi, M., Hofbauer, V., Hoyle, C. R., Kirkby, J., Kürten, A., Kvashnin, A. N., Laurila, T., Lawler, M. J., Mai, H., Makhmutov, V., Mauldin III, R. L., Molteni, U., Nichman, L., Nie, W., Ojdanic, A., Onnela, A., Piel, F., Quéléver, L. L. J., Rissanen, M. P., Sarnela, N., Schallhart, S., Sengupta, K., Simon, M., Stolzenburg, D., Stozhkov, Y., Tröstl, J., Viisanen, Y., Vogel, A. L., Wagner, A. C., Xiao, M., Ye, P., Baltensperger, U., Curtius, J., Donahue, N. M., Flagan, R. C., Gallagher, M., Hansel, A., Smith, J. N., Tomé, A., Winkler, P. M., Worsnop, D., Ehn, M., Sipilä, M., Kerminen, V.-M., Petäjä, T., and Kulmala, M.: The role of ions in new particle formation in the CLOUD chamber, Atmos. Chem. Phys., 17, 15181-15197,, 2017
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:84134
Deposited By: Tony Diaz
Deposited On:05 Jan 2018 22:01
Last Modified:15 Nov 2021 20:17

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