甘肃省秋季飞机人工增雨天气系统分型

为了探讨甘肃秋季人工增雨天气系统的影响特征，利用甘肃省1991-2002年飞机人工增雨作业资料，对秋季飞机人工增雨作业情况进行了统计分析；按照甘肃省秋季天气系统特征，利用探空资料，建立了甘肃省秋季天气系统自动化“判别模型”，得出甘肃秋季降水的高空环流可分为三种类型：平直多波动型、西南气流型和西北气流型，其中降水类型以平直多波动型为主。通过“判别模型”对飞机人工增雨天气系统的分型，结果表明飞机人工增雨作业的主要天气类型为西南气流型和平直多波动型。可为人工增雨作业区域选择和航线设计提供天气气候背景。

Weather System Types of Aircraft Artificial Precipitation Enhancement in Autumn in Gansu Province

To investigate features of the autumn weather system over Gansu Province in airplane artificial precipitation enhancement, statistical analysis was conducted, based on the data of air-plane artificial precipitation enhancement operations from 1991 to 2002. Meanwhile, discriminant model of the autumn weather system of Gansu was established by utilizing the information of sounding data and the autumn weather system features. The results show that upper air circulation of the autumn precipitation in Gansu can be divided into three categories i.e. straight and fluctuant flow pattern, southwest flow pattern and northwest flow pattern. Among those patterns, the straight and fluctuant flow pattern occurred more frequently than other two patterns.The results indicate that southwest and straight yet fluctuant flow patterns are suitable for aircraft artificial precipitation enhancement operation. The results can be used for choosing the seeding area and designing flight course in the artifical precipitation enhancement operation.