| Finding the right cloud precipitation microphysical characteristics in growing cloud is the key point of weather modification, satellite, radar and plane are the major ways to research into cloud macro and micro structure,however, every observation way has its advantages and disadvantages, the condition monitoring and effect analysis of artificial precipitation are very hard.. So, how to combine remote sensing methods,such as satellite and radar, and plane observation data, is very important to comprehensively analyze cloud macro and micro structure characteristics, which is also the key to improve the science level of weather modification.Combining the observations of satellite, radar, intensive air sounding, rainfall and plane cloud physics, the paper make a research on two artificial precipitation field experiments, which are operated on thel8th,April,2009and the20th,April,2010respectly. After analyzing cloud macro and micro structure characteristics and the change of ground precipitation before and after cloud seeding. The main results conclude as follows:1) The precipitation cloud of20th, April,2010, which happened in Zhang jiakou, Hebei province, is convective-stratiform mixed clouds with large amount of super-cooled liquid water, and is very suitable to be seeded. During the seeding event, the regions which are suitable to seed are the main part of operated clouds. There’s some corresponding relationship between the cloud seeding ability and radar echoes. The intensity of C-band radar echoes is in good relationship with precipitation particle spectrum, but in weak relativity of cloud particle spectrum. After seeding, the concentration of small-particle decreased, while large cloud droplets and raindrops concentration increased, and radar echo showed a bright band in the relevant position. Comparison analysis of target zone with control areas, it shows that rainfall increased in about three hours after seeding. 2)The precipitation cloud of Shanxi district.20th,April,2010,is typical stratiform cloud precipitation, the cloud top is about at the height of8km, liquid water content in cloud is not high.and the seedable is not very well, the area with maximum value mainly focus on the height of2500km to4500km. The diameters of big cloud particles rise with height; However, it shows a uniform particle distribution in horizontal,, the density has slightly ups and downs.What’s more, the maximum value area of precipitation particles corresponding to the low density of small cloud particles, but its low density area corresponding to high density small cloud particles. This precipitation case may be triggered by the ice-water switching mechanism. After the operation, the cloud top has the tendency to lower, the overall change of radar echo is not obvious, and the precipitation increases slightly. |
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