利用大连市气象局地基GPS/MET观测网大气可降水量（PWV）数据，分析2011年大连瓦房店、庄河和长海地区降水天气过程PWV的变化特征及其与降水量和降水强度的关系，在此基础上通过分析物理量场和天气系统，探讨大尺度水汽输送、辐合与PWV变化的关系及GPS在暴雨天气中的应用。结果表明：PWV的增长方式受当地天气系统的支配和制约，对一次明显的降水过程，从降水开始至结束PWV的变化与降水量有明显的相关性。当有水汽由南向北输送时，PWV在降水开始前逐渐增长，当地面及高空有大范围的水汽辐合且高空比湿值大于10 g·kg-1时，PWV显著增长（降水开始前4-5 h），主要降水时段与PWV峰值对应，同时PWV的增幅大小与降水强度有密切的关系。%Based on precipitable water vapor(PWV)data from GPS/MET observation network in Dalian,character-istics of PWV and its relationships with precipitation and precipitation intensity in Wafangdian,Zhuanghe and Changhai regions in 200 1 were analyzed.According to the above analysis and physical quantity field as well as weather system,relationships of PWV variation with large-scale water vapor transport convergence and moisture convergence,and application of GPS to a rainstorm process were discussed.The results show that increase of PWV is often restricted by the local weather system.For a clear precipitation process,PWV changes and precipitation have a clear relation from beginning to end of the precipitation process.When water vapor transports from south to north,PWV increases gradually before precipitation begins.When it has large range moisture convergence at sur-face and upper level,and specific humidity reaches above 10 g·kg -1 ,PWV increases significantly in previous 4-5 hours of rainstorm.Main precipitation period corresponds to the peak value of PWV.Meanwhile,PWV increment has a significant relation with precipitation intensity.
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