利用地基GPS数据分析北京“7·21”暴雨水汽特征  

Characteristics of Water Vapor in a Heavy Rainstorm Based on Ground-Based GPS Measurements in Beijing

作　　者：张恩红 曹云昌[2] 王晓英[3] 王洪[4] 

机构地区：[1]广东省气象探测数据中心,广州510080 [2]中国气象局气象探测中心,北京100081 [3]南京信息工程大学遥感学院,南京210044 [4]山东省气象信息中心,济南230031

出　　处：《气象科技》2015年第6期1157-1163,共7页Meteorological Science and Technology

基　　金：中国气象局华南区域气象中心科技攻关项目(GRMC2014M06)资助

摘　　要：基于北京＂7·21＂暴雨期间北京地基GPS网全天时全天候观测数据,利用水汽反演软件得到大气可降水量（PWV：Precipitable Water Vapor）时空变化序列,通过与探空对比,显示出地基GPS技术探测对流层大气水汽具明显的高时空分辨率优势;与FY2D卫星探测的云图变化序列对比,充分反映了利用GPS观测数据反演的PWV的可靠性与一致性;与实际降雨量对比,两者高度相关性显示了地基GPS技术对暴雨监测和预警的积极意义。数据分析结果表明：在暴雨来临之前的24~36h的PWV值持续在较高（〉40mm）的位置,已有出现暴雨征兆。在暴雨之前的几个小时PWV持续性爆发性发展（每小时PWV增加10~20mm）,已充分具备了产生暴雨的必要条件。因此,有效地利用GPSMET技术对天气预报的准度和精度将有很大改善。Continuous supply of water vapor is a necessary condition for the occurrence and development of a rainstorm.The ground-based GPS technology provides a new method for the detection of tropospheric water vapor,which provides technical guarantee for the accuracy and precision of weather forecast.The Bernese 5.0software was used to process the ground-based GPS data in a heavy rainstorm on 21 July 2012in Beijing.The temporal and spatial variation series of the PWV（Precipitable Water Vapor）are obtained and contrasted with radiosonde data.The results show that high spatial and temporal resolution groundbased GPS technology has obvious advantageous for the detection of atmospheric water vapor in the troposphere.The high correlation with the actual rainfall shows a positive significance of ground-based GPS technology in the monitoring and early-warning of rainstorms.The results indicate that when higher PWV（40mm）continues in Beijing,within 24 to 36hours there may occur a heavy rainfall;when PWV becomes very rich（increased 10 to 20mm per hour）with sustainable PWV development in short time,a storm may be coming.The effective application of GPSMET technology in weather forecast can improve the precision and accuracy greatly.

关 键 词：地基GPS 暴雨 可降水量 加权平均温度 

分 类 号：P426[天文地球—大气科学及气象学]