地基GPS斜路径水汽反演技术及资料应用初探  

Slant Path Water Vapor Retrieval with GPS and Application in Rainstorm Analysis

作　　者：万蓉[1] 付志康[1] 李武阶[2] 陈波[3] 于胜杰[1] 邹倩 

机构地区：[1]中国气象局武汉暴雨研究所,暴雨监测预警湖北省重点实验室,武汉430205 [2]武汉中心气象台,武汉430074 [3]湖北省气象局,武汉430074 [4]重庆市气象台,重庆401147

出　　处：《气象》2015年第4期447-455,共9页Meteorological Monthly

基　　金：国家自然科学基金项目(41375041);国家高技术研究发展计划(863计划)(2012AA120902);湖北省科技发展基金项目(2014Y06);中国气象局修缮购置专项共同资助

摘　　要：斜路径水汽总量(Slant pathWater Vapor,SWV)包含了一定的水汽非各向同性空间分布信息,是区域地基全球定位系统(Global Positioning System,GPS)网进行三维水汽层析的主要数据源;测站所得到的SWV时间序列,直观地反映接收机测站周边水汽的不均匀分布和动态变化特征。采用天顶可降水汽总量(PrecipitableWaterVapor,PWV)反演技术,以及湿映射函数构建、大气水平梯度模型构建、残差处理等技术,建立斜路径水汽总量解算算法。通过同步并址观测的1141个样本比较,在高仰角区间,GPS与微波辐射计对斜路径方向上水汽总量的观测平均偏差5.8 mm,均方差4.4 mm。在结合雷达、微波辐射计等观测对暴雨个例的综合分析中,SWV系列时序产品能较好地表现测站周边水汽堆积和降水发生后的水汽减少等细微特征。SWV作为一种新的观测产品,为天气分析提供了能反映测站周边水汽的分布状况的新信息,为强对流天气预警预报和机理分析提供新的研究角度。Slant path water vapor(SWV) contains the information of the nonisotropic distribution of water vapor in space,and it is the main data source for the 3D water vapor density analysis.The SWV time series obtained by observing stations directly the uneven distribution and changes of water vapor surrounding the station receiver.SWV algorithms is established by using the zenith precipitable total precipitable water vapor(PWV) inversion techniques,the wet mapping function,horizontal gradient function of wet atmospheric and the residual processing technology.By comparing the observations of GPS and microwave radiometer,we find the average deviation of SWV is 5.8 mm,and RMS is 4.4 mm in 50°-90° elevation range.In comprehensive analysis,the products of SWV time series that are combined with rainstorm observation cases by radar and microwave radiometer can better express the detailed features of the water vapor surrounding the station,such as the accumulation and the reduction of water vapor before and after the precipitation respectively,is which would be new reference information for the warning and forecasting of severe convection weather and related mechanism research.

关 键 词：GPS 斜路径 水汽总量 暴雨 

分 类 号：P412.2[天文地球—大气科学及气象学]