Snow scavenging of
sub-micrometre aerosol particles is poorly known, even though it is an important
aerosol removal mechanism in the polar and mountainous regions as well as in the
upper troposphere and in mid-latitudes in winter. In our study, snow scavenging
coefficients were calculated using four years of particle number concentration
spectra measurements together with meteorological measurements. The obtained
experimental median scavenging coefficients varied between 8.7 x 10^–6
s^–1 and 5.2 x 10^–5 s^–1 in the 10 nm to 1 um
size range. A parameterization of the results is presented and its functionality
is tested using University of Helsinki Multicomponent Aerosol model (UHMA). The
parameterization applies to snowfall types of slight continuous snowfall and
snow grains with intensities of the order of 0.1 mm
h^–1.