Observations of turbulence-induced new particle formation in the residual layer B. Wehner1, H. Siebert1, A. Ansmann1, F. Ditas1, P. Seifert1, F. Stratmann1, A. Wiedensohler1, A. Apituley2, R. A. Shaw1,3, H. E. Manninen4, and M. Kulmala4 1Leibniz Institute for Tropospheric Research, 04318 Leipzig, Germany 2RIVM – National Institute for Public Health and the Environment, 3720 BA Bilthoven, The Netherlands 3Department of Physics, Michigan Technological University, Houghton, MI 49931, USA 4Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland
Abstract. Aerosol particle measurements in the atmospheric boundary layer performed by a
helicopter-borne measurement payload and by a lidar system from a case study
during the IMPACT field campaign in Cabauw (NL) are presented.
Layers of increased number concentrations
of ultrafine particles were observed in the residual layer, indicating
relatively recent new-particle formation.
These layers were characterized by a sub-critical Richardson number and
concomitant increased turbulence. Turbulent mixing is likely to lead to
local supersaturation of possible precursor gases which are essential
for new particle formation. Observed peaks in the number concentrations
of ultrafine particles at ground level are connected to the new particle
formation in the residual layer by boundary layer development and vertical mixing.
Citation: Wehner, B., Siebert, H., Ansmann, A., Ditas, F., Seifert, P., Stratmann, F., Wiedensohler, A., Apituley, A., Shaw, R. A., Manninen, H. E., and Kulmala, M.: Observations of turbulence-induced new particle formation in the residual layer, Atmos. Chem. Phys., 10, 4319-4330, doi:10.5194/acp-10-4319-2010, 2010.