Journal cover Journal topic
Atmospheric Chemistry and Physics An interactive open-access journal of the European Geosciences Union
Journal topic

Journal metrics

Journal metrics

  • IF value: 5.509 IF 5.509
  • IF 5-year value: 5.689 IF 5-year 5.689
  • CiteScore value: 5.44 CiteScore 5.44
  • SNIP value: 1.519 SNIP 1.519
  • SJR value: 3.032 SJR 3.032
  • IPP value: 5.37 IPP 5.37
  • h5-index value: 86 h5-index 86
  • Scimago H index value: 161 Scimago H index 161
Volume 11, issue 2 | Copyright

Special issue: European Integrated Project on Aerosol-Cloud-Climate and Air...

Atmos. Chem. Phys., 11, 767-798, 2011
© Author(s) 2011. This work is distributed under
the Creative Commons Attribution 3.0 License.

Review article 26 Jan 2011

Review article | 26 Jan 2011

Atmospheric ions and nucleation: a review of observations

A. Hirsikko1, T. Nieminen1, S. Gagné1,2, K. Lehtipalo1, H. E. Manninen1, M. Ehn1, U. Hõrrak3, V.-M. Kerminen1,4, L. Laakso1,4,5, P. H. McMurry6, A. Mirme3, S. Mirme3, T. Petäjä1, H. Tammet3, V. Vakkari1, M. Vana1,3, and M. Kulmala1 A. Hirsikko et al.
  • 1Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland
  • 2Helsinki Institute of Physics and University of Helsinki, Department of Physics, P.O. Box 64, 00014 University of Helsinki, Finland
  • 3Institute of Physics, University of Tartu, 18 Ülikooli Str., 50090 Tartu, Estonia
  • 4Finnish Meteorological Institute, Research and Development, P.O. Box 503, 00101 Helsinki, Finland
  • 5School of Physical and Chemical Sciences, North-West University, Potchestroom, Republic of South Africa
  • 6Particle Technology Laboratory, University of Minnesota, Minneapolis, Minnesota, USA

Abstract. This review is based on ca. 260 publications, 93 of which included data on the temporal and spatial variation of the concentration of small ions (<1.6 nm in diameter) especially in the lower troposphere, chemical composition, or formation and growth rates of sub-3 nm ions. This information was collected on tables and figures. The small ions exist all the time in the atmosphere, and the average concentrations of positive and negative small ions are typically 200–2500 cm−3. However, concentrations up to 5000 cm−3 have been observed. The results are in agreement with observations of ion production rates in the atmosphere. We also summarised observations on the conversion of small ions to intermediate ions, which can act as embryos for new atmospheric aerosol particles. Those observations include the formation rates (J2[ion]) of 2-nm intermediate ions, growth rates (GR[ion]) of sub-3 nm ions, and information on the chemical composition of the ions. Unfortunately, there were only a few studies which presented J2[ion] and GR[ion]. Based on the publications, the formation rates of 2-nm ions were 0–1.1 cm−3 s−1, while the total 2-nm particle formation rates varied between 0.001 and 60 cm−3 s−1. Due to small changes in J2[ion], the relative importance of ions in 2-nm particle formation was determined by the large changes in J2[tot], and, accordingly the contribution of ions increased with decreasing J2[tot]. Furthermore, small ions were observed to activate for growth earlier than neutral nanometer-sized particles and at lower saturation ratio of condensing vapours.

Publications Copernicus
Special issue