Airborne observations of aerosol microphysical properties and particle ageing processes in the troposphere above Europe 1Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen, 82234 Wessling, Germany
04 Dec 2012
2School of Earth, Atmospheric and Environmental Sciences, University of Manchester, Manchester M13 9PL, UK
3Department of Applied Environmental Science (ITM), Stockholm University, 106 91 Stockholm, Sweden
*now at: Department of Applied Environmental Science (ITM), Stockholm University, 106 91 Stockholm, Sweden
**now at: Department of Atmospheric Science, Colorado State University, Fort Collins, CO 80523, USA
***now at: Institut für Energie- und Klimaforschung IEK-8: Troposphäre, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
Received: 02 August 2012 – Published in Atmos. Chem. Phys. Discuss.: 15 August 2012 Abstract. In-situ measurements of aerosol microphysical properties were performed in
May 2008 during the EUCAARI-LONGREX campaign. Two aircraft, the FAAM BAe-146
and DLR Falcon 20, operated from Oberpfaffenhofen, Germany. A comprehensive
data set was obtained comprising the wider region of Europe north of the Alps
throughout the whole tropospheric column. Prevailing stable synoptic
conditions enabled measurements of accumulating emissions inside the
continental boundary layer reaching a maximum total number concentration of
19 000 particles cm−3 stp. Ultra-fine particles as indicators for
nucleation events were observed within the boundary layer during high
pressure conditions and after updraft of emissions induced by frontal
passages above 8 km altitude in the upper free troposphere. Aerosol ageing
processes during air mass transport are analysed using trajectory analysis.
The ratio of particles containing a non-volatile core (250 °C) to the
total aerosol number concentration was observed to increase within the first
12 to 48 h from the particle source from 50 to 85% due to coagulation.
Aged aerosol also features an increased fraction of accumulation mode
particles of approximately 40% of the total number concentration. The
presented analysis provides an extensive data set of tropospheric aerosol
microphysical properties on a continental scale which can be used for
atmospheric aerosol models and comparisons of satellite retrievals.
Revised: 20 November 2012 – Accepted: 27 November 2012 – Published: 04 December 2012
Citation: Hamburger, T., McMeeking, G., Minikin, A., Petzold, A., Coe, H., and Krejci, R.: Airborne observations of aerosol microphysical properties and particle ageing processes in the troposphere above Europe, Atmos. Chem. Phys., 12, 11533-11554, doi:10.5194/acp-12-11533-2012, 2012.