JICA项目地基GPS大气可降水量资料精度检验  

Accuracy Test of JICA Project Ground-Based GPS Precipitable Water Vapor

作　　者：马思琪[1] 周顺武[2] 王毅勇[1] 孙绩华[3] 

机构地区：[1]中国科学院东北地理与农业生态研究所湿地生态与环境重点实验室,吉林长春130012 [2]南京信息工程大学大气科学与环境气象国家级实验教学示范中心,江苏南京210044 [3]云南省气象科学研究所,云南昆明650034

出　　处：《干旱区研究》2017年第3期575-584,共10页Arid Zone Research

基　　金：国家自然科学基金项目(41275095);宁夏气象防灾减灾重点实验室开放研究基金;科技部公益性行业(气象)科研专项(GYHY201406054;GYHY201406001);国家重点研发计划课题(2016YFA0602003)资助

摘　　要：利用中日JICA项目2011—2012年位于青藏高原及其东部山区6个GPS探测的逐时大气可降水量(GPSPWV)以及探空观测计算得到的每日2个时次(0:00 UTC和12:00 UTC)的大气可降水量资料(RS-PWV),验证GPS-PWV资料的准确度,分析了其误差的分布特征,并初步探讨了地面气温对误差的影响。结果表明:(1)受海拔高度的影响,GPS-PWV普遍比RS-PWV偏高;受水汽含量的影响,12:00 UTC的偏差普遍大于0:00 UTC,但两者之间逐日变化具有很好的一致性,其相关关系通过了0.001的显著性检验。(2)各站GPS-PWV和RS-PWV的平均均方根误差(RMSE)在0.23~0.33 cm,平均相对误差(MRE)在9.13%~29.01%,RMSE(MRE)随着站点海拔高度降低而增大(减小)。(3)各站PWV存在明显的季节差异,其PWV偏差同样具有明显的年变化特征:在7—9月最大,在12月至次年3月较低。(4)各站PWV偏差频率分布在0:00 UTC的峰值中心位于0 cm,偏差主要集中在-0.1~0.1 cm,而12:00 UTC的峰值中心相对右移,峰值要比0:00 UTC低,偏差值分布较分散。(5)在一定温度范围内,随着地面温度升高,PWV偏差有所增加。A project from the Japan International Cooperation Agency （JICA） was carried out during the period from 2005 to 2009, in which 24 ground-based GPS stations were established in the Tibetan Plateau and its peripher- al regions. In this paper, the GPS-retrieved precipitable water vapor data （GPS-PWV） of JICA during the period from 2011 to 2012 were compared with the PWV values calculated by radiosonde （RS-PWV） at 0：00 and 12：00 UTC, the accuracy of GPS-PWV data of JICA project was tested, and the error variations and the influences of tem- perature were analyzed. The results are as follows： （1） Daily variations of GPS-PWV and RS-PWV were consistent and passed the significant test of 0. 001, but the GPS-PWV was higher because of the lower altitudes of the GPS sta- tions. The correlation coefficients were increased with the decrease of altitude; （2）The average RMSE （MRE） be- tween GPS and radiosonde PWV was 0.23 -0.33 cm （9.13% -29.01% ） ,and the RMSE （MRE） was generally increased （decreased） with the decrease of altitude ; （3） There was an obvious seasonal difference in the PWV vari- ation and the bias of PWV ： the maximum value occurred during the period from July to September, and the low val- ue from December to next March. （4） The peak center of frequency distribution of PWV bias at 0：00 UTC was loca- ted at 0 cm,and the PWV biases were mainly concentrated between -0.1 and 0.1 cm. The peak center at 12：00 UTC moved rightward, the maximum was lower, and the distribution was scattered; （5） In a certain temperature range, the PWV bias was increased to some extent with the temperature increase.

关 键 词：地基GPS 探空观测 大气可降水量 精度检验 

分 类 号：P412.2[天文地球—大气科学及气象学]