title: Collocated observations of cloud condensation nuclei, particle size distributions, and chemical composition.
abstract: Cloud condensation nuclei (CCN) number concentrations alongside with submicrometer particle number size distributions and particle chemical composition have been measured at atmospheric observatories of the Aerosols, Clouds, and Trace gases Research InfraStructure (ACTRIS) as well as other international sites over multiple years. Here, harmonized data records from 11 observatories are summarized, spanning 98,677 instrument hours for CCN data, 157,880 for particle number size distributions, and 70,817 for chemical composition data. The observatories represent nine different environments, e.g., Arctic, Atlantic, Pacific and Mediterranean maritime, boreal forest, or high alpine atmospheric conditions. This is a unique collection of aerosol particle properties most relevant for studying aerosol-cloud interactions which constitute the largest uncertainty in anthropogenic radiative forcing of the climate. The dataset is appropriate for comprehensive aerosol characterization (e.g., closure studies of CCN), model-measurement intercomparison and satellite retrieval method evaluation, among others. Data have been acquired and processed following international recommendations for quality assurance and have undergone multiple stages of quality assessment.
authors.affiliation: Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland.
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authors.identifier: 0000-0002-1048-7962
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authors.affiliation: Netherlands Organisation for Applied Scientific Research, Princetonlaan 6, Utrecht 3584, The Netherlands.
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authors.affiliation: Department of Physics, University of Helsinki, Gustaf Hällströmin katu 2, Helsinki 00014, Finland.|Hyytiälä Forestry Field Station, Hyytiäläntie 124, Korkeakoski 35500, Finland.
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authors.affiliation: ECPL, Department of Chemistry, University of Crete, Voutes, Heraklion 71003, Greece.|IERSD, National Observatory of Athens, P. Penteli, Athens 15236, Greece.
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authors.affiliation: ECPL, Department of Chemistry, University of Crete, Voutes, Heraklion 71003, Greece.|IERSD, National Observatory of Athens, P. Penteli, Athens 15236, Greece.
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authors.affiliation: Institute for Marine and Atmospheric Research, University of Utrecht, Utrecht 3508 TC, The Netherlands.|Institute for Energy and Climate Research (IEK-8): Troposphere, Forschungszentrum Jülich, Jülich 52425, Germany.
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authors.identifier: 0000-0002-0206-8987
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authors.affiliation: Department of Physics, Lund University, Lund 221 00, Sweden.
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authors.affiliation: Department of Physics, University of Helsinki, Gustaf Hällströmin katu 2, Helsinki 00014, Finland.
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authors.affiliation: Experimental Aerosol &Cloud Microphysics, Leibniz Institute for Tropospheric Research, Permoserstrasse 15, Leipzig 04318, Germany.|Federal Environment Agency, Corrensplatz 1, Berlin 14195, Germany.
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authors.affiliation: Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland.
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authors.affiliation: Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland.
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authors.affiliation: Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland.|Grolimund+Partner AG, Thunstrasse 101a, Bern 3006, Switzerland.
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authors.affiliation: ECPL, Department of Chemistry, University of Crete, Voutes, Heraklion 71003, Greece.|IERSD, National Observatory of Athens, P. Penteli, Athens 15236, Greece.
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authors.affiliation: Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland.
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authors.affiliation: Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen 5232, Switzerland.
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