Towards Direct Measurement of Atmospheric Nucleation

Research output: Contribution to journalArticle

Authors

  • K Kulmala
  • I Riipinen
  • M Sipila
  • HE Manninen
  • T Petaja
  • H Junninen
  • M Dal Maso
  • G Mordas
  • A Mirme
  • M Vana
  • A Hirsikko
  • L Laakso
  • Ian Hanson
  • KEJ Lehtinen
  • V-M Kerminen

Colleges, School and Institutes

Abstract

Atmospheric aerosol formation is known to occur almost all over the world, and the importance of these particles to climate and air quality has been recognized. Although almost all of the processes driving aerosol formation take place below a particle diameter of 3 nanometers, observations cover only larger particles. We introduce an instrumental setup to measure atmospheric concentrations of both neutral and charged nanometer-sized clusters. By applying the instruments in the field, we come to three important conclusions: (i) A pool of numerous neutral clusters in the sub-3 nanometer size range is continuously present; (ii) the processes initiating atmospheric aerosol formation start from particle sizes of approximately 1.5 nanometers; and (iii) neutral nucleation dominates over the ion-induced mechanism, at least in boreal forest conditions.

Details

Original languageEnglish
Pages (from-to)89-92
Number of pages4
JournalScience
Volume318
Publication statusPublished - 5 Oct 2007