Analyses on Vertical Microphysical Characteristics of Autumn Stratiform Cloud in Lanzhou Region

The vertically sounding data of the stratiform cloud over Zhongchuan Air Port of Gansu in 5 weather processes in September and October 2001 measured by the airborne PMS probes and hygrothermoscope have been used. The data cover microphysical characteristics of autumn stratiform clouds such as Cs-As-Ns and Ac-Sc, cloud particle density, diameter, liquid water concentration and relative temperature. The cloud particle spectra were fitted by using a N order Γ type function and the optimum parameters were picked out. It is pointed out that the position of inversion layer corresponding to the 0℃ layer and the inversion intensity have obvious influence on the distribution of cloud microphysical characteristics and form of precipitation.