祁连山地形云人工增雨(雪)试验观测与研究进展

Observations and Research Progress of Cloud-Seeding(Snow)Project in Qilian Mountains

系统概括了西北区域人工影响天气能力建设项目“西北区域人工影响天气工程祁连山地形云人工增雨(雪)技术研究试验”的研究进展,可归纳如下:按照项目计划顺利开展了野外探测试验以及火箭、飞机观测试验,收集了各种手段获取的各要素探测数据及作业相关信息,开展了各种作业方法的效果检验和评估;分析了祁连山地区降水量场和气流场特征;探讨了试验仪器及再分析数据和卫星数据的精确性,对FY-3A/MERSI水汽产品、TK-2GPS人影探测火箭资料进行了精度验证,对微波辐射计温湿度的反演方法进行了探讨;从云垂直结构、云粒子特征、水汽等方面对祁连山地区云、水资源的变化特征进行了研究;对人工增雨效果进行了统计检验;利用WRF中尺度数值模式对地形云降水个例进行了模拟研究,探讨了祁连山地形云和降水的发生发展机制。初步研究结果表明:祁连山地区平均年降水量为232.4 mm,祁连山区流场主要有西南及偏西气流型,辐合辐散气流型,东北及偏东气流型,西北及偏北气流型,偏南气流型等五种类型;祁连山北坡云的发生频率较低,仅为20%~40%;降水和气温分别使径流量增加了21.1%和10.9%;石羊河流域2010年以来,4—10月人工增雨绝对增雨量为33.7 mm,平均相对增雨率为17.5%,平均植被覆盖百分比达到了46%以上并保持稳定;夏季祁连山区地形抬升局地性强,地形抬升作用对降水影响很大,过程降水一般都包含着地形云降水。

Systematically summed up the research progress of“weather modification project of topographic cloud precipitation(snow)enhancement technology research and experiment in Qilian mountain”,the research progress can be summarized as follows:according to the plan of the project,field detection tests and aircraft observation tests were carried out successfully,and the detection data and weather modification operation of various elements obtained by various means were collected,which provided data support for the effect inspection and evaluation of various operational methods.The characteristics of precipitation field and air flow field in Qilian Mountains are analyzed.The accuracy of instruments and satellite data were verified,the accuracy of FY-3A/MERSI water vapor product and TK-2GPS rocket data were verified,and the inversion method of temperature and humidity of microwave radiometer was discussed.The variation characteristics of cloud and water resources in Qilian Mountains were studied from the aspects of cloud vertical structure,cloud particle characteristics and water vapor.The effect of artificial precipitation enhancement was tested statistically.Simulated the topographic cloud precipitation cases and discussed the occurrence and development mechanism of topographic cloud and precipitation in Qilian Mountains by used WRF mesoscale numerical model.Preliminary results show that:the average annual precipitation in the Qilian Mountains is 232.4 mm;the flow field in the Qilian Mountains region mainly consists of southwest and west flow pattern,convergence and divergence flow pattern, northeast and east flow pattern, northwest and north flow pattern, and south flow pattern;the occurrence frequency of clouds on the Northern Slope of Qilian Mountains is only 20%−40%;precipitation and temperature increased the runoff by 21.1% and 10.9%, respectively;the absolute precipitation increase of artificial precipitation in Shiyang River Basin from April to October was 33.7 mm, the average relative precipitation increase rate was 17.5%, and the average vegetation coverage percentage was more than 46% and remained stable;in summer, the uplift of the Qilian Mountains has a strong local character, and the uplift has a great influence on the precipitation, and the process precipitation usually includes the topographic cloud precipitation.