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Formation speed of smaller nucleation particles evaluated with the help of larger ones

Formation speed of smaller nucleation particles evaluated with the help of larger ones

A study by the University of Eastern Finland, the Finnish Meteorological Institute, and the University of Helsinki defined the formation speed for particles 2 nm (nanometres, or one millionth of a millimetre) with the help of the formation speed and growth speed of larger-sized particles, 7 nm in size.

The estimates were made on particles measured over a period of eight years (2007–2015) at the SMEAR*IV measuring station located at the Puijo Tower in Kuopio. The average formation speed of particles 7 nm in size was 0.44 cm-3s-1 and the estimated formation speed for 3 nm particles was 0.61 cm-3s-1. This means that about one particle is formed in one square centimetre of air (about the volume of a sugar cube) every two seconds.

More information:

Researcher Ari Leskinen, tel. +358 50 522 9148,

Professor Kari Lehtinen, University of Eastern Finland, tel. +358 40 8677 844,

Baranizadeh E., Nieminen T., Yli-Juuti T., Kulmala M., Petäjä T., Leskinen A., Komppula M., Laaksonen A. & Lehtinen K.E.J. 2017. Estimation of atmospheric particle formation rates through an analytical formula: Validation and application in Hyytiälä and Puijo, Finland. Atmos. Chem. Phys., 17, 13361-13371, doi:10.5194/acp-17-13361-2017


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