Research On Region Precipitable Water Vapor Retrieval Using SDCORS Data

With the development of ground-based GPS(Globle Positioning System)technology and the rapid development of GPS meteorology,the use of ground-based GPS detection technology has become a new and effective method for atmospheric vapor detection.In addition,more and more regional CORS(Continuously Operating Referemce System)systems have been constructed,and CORS inversion of atmospheric vapor has attracted increasing attention.Compared with traditional methods,regional CORS inversion of atmospheric precipitable water has the advantages of high precision,wide coverage,continuous observation in all weather,high spatial and temporal resolution,and low cost.Therefore,the meteorological departments and researchers at home and abroad conducted a series of studies to improve the accuracy,real-time and practicality of CORS inverting atmospheric precipitable water vapor,and to explore its potential in meteorology in order to serve people better and more effectively.Based on SDCORS(Shandong Continuously Operating Referernce System),the principle and method of regional CORS inversion of water vapor were analyzed.In view of the obvious spatial-temporal characteristics of weighted mean temperature and the regional errors in existing models,a weighted mean temperature model suitable for Shandong Province was established.The accuracy of the SDCORS inversion of water vapor was evaluated and examined,and the correlation between the CORS inverting atmospheric precipitable water vapor and the actual precipitation was analyzed.The main research contents and results are as follows.1.Since most of the CORS stations are not equipped with meteorological sensors and no meteorological data are measured,the applicability of the weighted mean temperature values of the GPT2 model and the GGOS Atmosphere interpolation in the Shandong area were analyzed,providing data support for the establishment of the weighted mean temperature model for Shandong.2.Since there are only two radio stations in Shandong Province and the distribution is sparse,the weighted mean temperature model established using this model cannot represent the entire Shandong region.Therefore,it was proposed to use 4 radio stations(2 radio stations in Shandong and 2 nearby radio stations)+9 stations taking into account the uniform distribution of elevation and space in Shandong Province,and using the GPT2 model and GGOS Atmosphere to obtain surface meteorological parameters and weighted mean temperature values,and then the weighted mean temperature model suitable for Shandong Province was established.It was showed that the seasonal model based on surface temperature and vapor pressure has higher stability and reliability with 0.26K?0.35K.3.It was founded that whether SDCORS/PWV calculated from the seasonal model of surface temperature and vapor pressure and the surface meteorological parameters estimated by GPT2,or GAMIT/PWV directly solved by GAMIT,were highly consistent with Radio/PWV calculated from radiosonde data.And SDCORS/PWV accuracy was better than GAMIT/PWV.4.Through comparative analysis with actual precipitation,it is found that SDCORS has a corresponding relationship between inversion of atmospheric precipitable water and actual precipitation,especially strong precipitation.The actual precipitation is related to the PWV value or the PWV mutation amount,and the probability of detecting precipitation is as high as more than 80%.It is of practical significance to monitor the water vapor.