www.atmos-chem-phys-discuss.net/9/19435/2009/ doi:10.5194/acpd-9-19435-2009 © Author(s) 2009. This work is distributed under the Creative Commons Attribution 3.0 License. Atmospheric sub-3 nm particles at high altitudes 1Institute of Physics, University of Tartu, Ülikooli 18, 50090, Tartu, Estonia 2Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany 3Finnish Meteorological Institute, P.O. Box 503, 00101, Helsinki, Finland 4Department of Physics, University of Helsinki, P.O. Box 64, 00014, Helsinki, Finland Abstract. Formation of new atmospheric aerosol particles is known to occur almost all over the world and the importance of these particles to climate and air quality has been recognized. Recently, it was found that atmospheric aerosol formation begins at particle diameter of around 1.5–2.0 nm and a pool of sub-3 nm atmospheric particles – consisting of both charged and uncharged ones – was observed at the ground level. Here, we report on the first airborne observations of the pool of sub-3 nm neutral atmospheric particles. Between 2 and 3 nm, their concentration is roughly two orders of magnitude larger than that of the ion clusters, depending slightly on the altitude. Our findings indicate that new particle formation takes place actively throughout the tropospheric column up to the tropopause. Particles were found to be formed via neutral pathways in the boundary layer, and there was no sign of an increasing role by ion-induced nucleation toward the upper troposphere. Clouds, while acting as a source of sub-10 nm ions, did not perturb the overall budget of atmospheric clusters or particles. Discussion Paper (PDF, 3269 KB) Interactive Discussion (Closed, 6 Comments) Final Revised Paper (ACP) Special Issue Citation: Mirme, S., Mirme, A., Minikin, A., Petzold, A., Hõrrak, U., Kerminen, V. -M., and Kulmala, M.: Atmospheric sub-3 nm particles at high altitudes, Atmos. Chem. Phys. Discuss., 9, 19435-19470, doi:10.5194/acpd-9-19435-2009, 2009. Bibtex EndNote Reference Manager XML |