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Cerina Wittbom. Photo.

Cerina Wittbom

Research coordinator

Cerina Wittbom. Photo.

Collocated observations of cloud condensation nuclei, particle size distributions, and chemical composition


  • Julia Schmale
  • Silvia Henning
  • Bas Henzing
  • Helmi Keskinen
  • Karine Sellegri
  • Jurgita Ovadnevaite
  • Aikaterini Bougiatioti
  • Nikos Kalivitis
  • Iasonas Stavroulas
  • Anne Jefferson
  • Minsu Park
  • Patrick Schlag
  • Adam Kristensson
  • Yoko Iwamoto
  • Kirsty Pringle
  • Carly Reddington
  • Pasi Aalto
  • Mikko Äijälä
  • Urs Baltensperger
  • Jakub Bialek
  • Wolfram Birmili
  • Nicolas Bukowiecki
  • Mikael Ehn
  • Ann Mari Fjæraa
  • Markus Fiebig
  • Göran Frank
  • Roman Fröhlich
  • Arnoud Frumau
  • Masaki Furuya
  • Emanuel Hammer
  • Liine Heikkinen
  • Erik Herrmann
  • Rupert Holzinger
  • Hiroyuki Hyono
  • Maria Kanakidou
  • Astrid Kiendler-Scharr
  • Kento Kinouchi
  • Gerard Kos
  • Markku Kulmala
  • Nikolaos Mihalopoulos
  • Ghislain Motos
  • Athanasios Nenes
  • Colin O'Dowd
  • Mikhail Paramonov
  • Tuukka Petäjä
  • David Picard
  • Laurent Poulain
  • Erik Swietlicki
  • Birgitta Svenningsson
  • Cerina Wittbom

Summary, in English

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.


  • Nuclear physics
  • MERGE: ModElling the Regional and Global Earth system
  • Consortium for Aerosol Science and Technology at Lund University (CAST)
  • Centre for Environmental and Climate Science (CEC)
  • Department of Physics

Publishing year





Scientific Data



Document type

Journal article


Nature Publishing Group


  • Oceanography, Hydrology, Water Resources




  • ISSN: 2052-4463