湖南省柘溪水库流域空中水汽资源特征及人工增雨潜力

Water Vapor Resource and Potentiality of Increasing Rain Artificiallyin Zhexi Reservoir and Its Drainage Area of Hunan Province

根据湖南省境内怀化和长沙2个探空站的1994—2003年1—12月每日两个时次(北京时间08时和20时)的资料,对柘溪水库库区及流域大气中的垂直气柱水汽含量进行了计算与分析。结果表明,柘溪水库流域全年年平均水汽含量值为3.62g·cm-2。各种天气形势下水汽含量值各不相同,台风外围云系水汽含量值相对较大,为6.01g·cm-2。大气垂直气柱水汽含量交换次数平均为3.04次/月,更新率为9.92天。柘溪流域上空平均每年净输入的水汽含量为234.87×108m3。若对所有的可作业云系施加人工影响,全年平均可能增雨总量达29.843×108m3。

Based on the sounding data at Huaihua and Changsha weather stations, Hunan Province from 1994 to 2003, the cloud water vapor content in the vertical atmosphere columniation are analyzed and computed over Zhexi reservoir and drainage area of Hunan province. It shows that the annual average value of cloud water vapor content is 3.62g · cm^-2 and varies with the synoptic： pattern in Zhexi reservoir and drainage area. The cloud system water vapor content value near the outer edges of the typhoon is 6.01g · cm ^2, greater than other cloud, Average exchange times of water vapor content is 3.04 times per month in vertical atmosphere columniation and updating ratio of water vapor is 9.92 days. Average net water vapor content into the atmosphere in Zhexi drainage area in one year is 23487 million m^3. It is possible that precipitation enhancement gross value would be about 2984.3 million m^3, if all potential clouds in the sky in this area are seeded.