区域GPS网对夏季降雨过程中大气可降水量的探测

Detection on the Precipitable Water Vapor During Summer Rainfall by Nanjing GPS Network

利用GPS网的观测资料,通过GAMIT软件求得5个测站对流层天顶总延迟,进而求出各测站对流层湿延迟;利用湿延迟与大气可降水量之间的转换关系得到各测站的大气可降水量。将所得GPS-PWV值与同时段探空资料所得的大气可降水量以及地表实际降水量进行对比分析,结果表明:GPS-PWV值与探空资料所得的PWV值比较相符;在降水前后,GPS-PWV有比较明显的变化,降水一般出现在GPS-PWV值迅速增加的4-6h内;实际降水量峰值与GPS-PWV增量大小也有较强的相关性。

Based on the observation data of GPS network,the tropospheric zenith delay of the five stations was calculated by GAMIT software,and the wet zenith delays was obtained.According to the conversion relation between wet delay and atmospheric precipitation,all stations＇ precipitable water vapor was calculated,and ompared with the radiosonde PWV and the ground rainfall,the results showed that：the GPS-PWV and the radiosonde PWV was quite consentaneous.During precipitation,GPS-PWV may have obvious changes,and rainfall was observed in 4-6 hours after the value of GPS-PWV had a rapid increase;finally,the actual precipitation peak was closely related with the increments of GPS-PWV.