上海地区地基GPS水汽三维层析技术和初步应用  

The 3D Tomography Technique and Application of Water Vapor Using Ground-based GPS Networks in Shanghai

作　　者：刘敏[1] 郭鹏[2] 叶其欣[1] 张洁[1] 朱雪松[1] 

机构地区：[1]上海市卫星遥感与测量应用中心,上海201100 [2]中国科学院上海天文台,上海200030

出　　处：《天文学报》2010年第3期299-308,共10页Acta Astronomica Sinica

基　　金：国家科技部863计划(2006aa12a107);灾害天气国家重点实验室开放课题(2009LASW-B10)资助项目

摘　　要：地基GPS(Global Positioning System)探测大气水汽主要包括3个方面的内容:一是观测天顶方向的大气水汽总量(Precipitable Water vapor,PW);二是遥测倾斜的信号路径上的水汽总量(Slant-path Water vapor,SW);三是应用组网的GPS站倾斜路径观测反演局地上空的水汽三维信息,即水汽层析(watervapor tomography)技术.简单介绍了上海地区稠密的地基GPS网,并且在该网的基础上通过GAMIT软件计算出的整层水汽PW和各个方向上的梯度信息及观测残差,来获得GPS测定的SW,运用层析的技术可获得上海地区水汽的三维分布信息.以2008年8月25日上海罕见的大暴雨为例,分析了水汽三维结果在强对流天气中的应用.Precipitable water vapor （PW） is a column average of atmospheric water vapor over both space and time and is estimated by GPS （Global Positioning System）. The signals from GPS are used to retrieve the integrated quantity of water vapor along the path between a transmitting satellite and a receiving station. This quantity is called slant water vapor （SW）. Measurements of SW allow for an improved assessment of the spatial distribution of water vapor within the atmosphere, which is called tomography technique. These are the main methods of remote-sensing water vapor by GPS. There are dense networks of GPS stations in Shanghai. These networks are used to assess the 3D distri-butions of water vapor. Taking a heavy storm in the city center on Aug. 25th 2008 as an example, the 3D distributions of water vapor supply more information for the weather analyses compared with the traditional atmospheric sounding ways. It is proved that the tomography technique is very useful for the disastrous weather.

关 键 词：天体测量 大气效应 方法:数值 

分 类 号：P128[天文地球—天体测量]