黄河上游降水云层对流特性及降水微结构机制研究

A Study on Convective Characteristics and Formation Mechanism of Precipitation over Upper Reaches of Yellow River

主要利用1997—2000年6～9月在黄河上游河曲地区实施人工增水实验所获取的各类降水云层回波、雨滴谱及多点宏观气象资料,进一步阐明各类云层降水中对流作用的普遍性和特殊性,并且通过全过程的雨滴谱的演变个例,初步揭示了该地区云中降水微物理过程可能存在冷云和暖云两种机制且暖云机制起重要作用。以上是该地区产生降水频繁的重要原因。

The generality and particularity of convective function for rainfall in each kind of clouds were further explained using the radar echo data, surface observation data and rain particle spectrums data over the upper reach area of Yellow River from June to september 1997\_2000. Through the case study of rain particle spectrum evolution, we preliminary infer that the microphysical processes of rainfall in cloud probably have two formation mechanisms of warm rain and cold rain, but the warm rain mechanism play an important part in precipitation development of cloud. The above\|mentioned facts may be the important reason of frequent rainfall in Qinghai\|Xizang Plateau