Contribution of mixing in the ABL to new particle formation based on observations J. Lauros1,2, E. D. Nilsson2, M. Dal Maso1, and M. Kulmala1 1Division of Atmospheric Sciences, Department of Physical Sciences, P.O. Box 64, 00014 University of Helsinki, Finland 2Department of Applied Environmental Science, Stockholm University, 10691 Stockholm, Sweden
Abstract. The connection between new particle formation and micro- and mesoscale
meteorology was studied based on measurements at SMEAR II station in
Southern Finland. We analyzed turbulent conditions described by sodar
measurements and utilized these combined with surface layer
measurements and a simple model to estimate the upper boundary layer
conditions. Turbulence was significantly stronger on particle
formation days and the organic vapor saturation ratio increase due to
large eddies was stronger on event than nonevent days. We examined
which variables could be the best indicators of new particle formation
and concluded that the formation probability depended on the
condensation sink and temporal temperature change at the top of the
atmospheric boundary layer. Humidity and heat flux may also be good
indicators for particle formation.
Citation: Lauros, J., Nilsson, E. D., Dal Maso, M., and Kulmala, M.: Contribution of mixing in the ABL to new particle formation based on observations, Atmos. Chem. Phys., 7, 4781-4792, doi:10.5194/acp-7-4781-2007, 2007.