基于对大气中水汽重要性及GPS测量大气水汽优势的双重认识,进入本世纪以来,华东区域各省气象部门联合与测 绘院、天文台等其他部门建起了相当规模的GPS气象探测网(GPS/MET)。根据2010年华东区域地基GPS/MET数据,选择 与GPS站相距10 km内的无线电探空站资料,对华东区域地基GPS/MET反演的大气整层可降水量(PWV)、大气整 层湿延迟(ZWD)和大气整层总延迟(ZTD)进行精度检验,结果表明: (1)GPS/MET反演的PWV与探空结果相比具有 很高的一致性,平均误差在1 mm以下,相对误差11.54%; GPS/ZTD反演的精度更高,百分比误差小于1%。(2)反 演的各个量与探空资料具有很高的相关性,其中平均相关系数中PWV和ZWD都超过0.98, ZTD为0.977。对GPS/PWV精度 按季节进行相关系数分析得,除夏季相关系数为0.927,相对较低,其余季节相关系数均为0.96以上。(3)以本地 的无线电探空站资料为基准,与NCEP再分析资料对比发现GPS/PWV的反演精度要优于NCEP再分析场资料反演 的大气整层可降水量。因此区域GPS/MET网反演的产品对提高灾害性天气的监测和预报能力, 改进数值 天气预报精度已显示出广阔的应用前景。

Based on the importance of water vapor in the atmosphere and the advantage of GPS in measuring atmospheric water vapor, several departments, including meteorological departments, institute of surveying and mapping, and astronomical observatory in East China, have established the GPS/MET network. Data is collected to analyze the accuracy of precipitable water vapor (PWV), zenith wet delay (ZWD) and zenith total delay (ZTD), which are derived by GPS/MET. It is compared with radiosonde data within 10 km from GPS stations. The result shows that: (1) The PWV data obtained by inversion of GPS/MET have high consistency with radionsonde result, the average error is less than 1 mm and the relative error is 11.54%. Moreover, the accuracy of GPS/ZTD is even higher and the relative error is less than 1%. (2)The correlation coefficients between inversion of each quantity and radionsonde result are high. Specifically, the coefficients of PWV and ZWD are more than 0.98, while the coefficient of ZTD is 0.977. Apart from that in summer, the coefficient of GPS/PWV is 0.927, and it is more than 0.96 in other seasons. (3)Based on the results of radiosonde data, the accuracy of GPS/PWV is better than results derived by NECP data. It has a broad application prospect in improving the severe weather monitoring, and prediction ability and the numerical weather forecast accuracy.