Pa. Vaillancourt et al., UPSHEAR AND DOWNSHEAR EVOLUTION OF CLOUD STRUCTURE AND SPECTRAL PROPERTIES, Journal of the atmospheric sciences, 54(9), 1997, pp. 1203-1217
A dynamical model, in conjunction with a microphysical model designed
to predict evolution of cloud droplet spectra, is employed to perform
two-dimensional simulations of a small nonprecipitating cumulus cloud
in the presence of wind shear. Upshear-downshear differences in terms
of entrainment sites, mixing zones, degree of dilution, and spectral p
roperties are investigated and compared to some observations. Results
show no systematic differences between the upshear and downshear sides
of individual cloud turrets composed of cloudy air of rather uniform
age. However, important differences in the spectral properties are not
ed between new cloudy air growing on the upshear side of the cloud and
older cloudy volumes dissipating on the downshear side of the cloud.
It is found that stronger wind shear inhibits the interaction between
cloud turrets of different ages.