Study On The Operation And Application Of The Ground-based GPS In Hebei

At present, the Ground-based GPS/MET is widely used in the meteorological field. In order to make great use of the the first operational System of Hebei province setted by the China Meterological administration and discuss the raising ability of the GPS data in forecasting the precipitation , the application of the GPS retrieval precipitable water of Shijiazhuang , Zhangjiakou and Qinghuangdao from the year 2005 to 2006 is studied.As a result, the operational system based on the Ground-based GPS, the data communication transmission software and the graphics display system of GPS/PWV all go well, and can be used in the daily operation as well as the forecast process.Comparing the precipitable water gained from the sounding data to the one received from the GPS, we realize that the GPS retrieval of precipitable water is more reliable, but for the single station , the effective radius of the GPS retrieval of precipitable have some limitations.After analyzing the data of GPS/PWV in Shijiazhuang , Zhangjiakou and Qinghuangdao from April to November in 2005,the temporal and spatial characteristics of precipitable water vapor in Hebei province was gained .which indicates the seasonal and regional characteristics of the precipitation in Hebei. Especially during June to August of 2005, the features of the GPS/PWV changes almost the same as that of the rainy period and the less-rainy period.The monthly average precipitable water vapor of GPS/PWV during Non-Raining period can be defined as threshold value when using the GPS/PWV forecasting the preciptation and it is a good indicator for the rainfall. According to the different analysis about the synoptic system which influences the precipitation, the variation characters of PWV about different synoptic system are not the same, but in the early 24 hours of most raining processes, the PWV data increases 4 to 5 millimeters in 3 hours, so it can be one of the indicators forecasting the precipitation .However, the relationship between the one-hour precipitation and both the increment and the maximum of the PWV is not so obvious.After the experiment about the GPS data in single stations, the conclusion was draw that after the stratiform clouds being catalysed by the rocket for 3 hours, the PWV of the atmosphere decreased but the amount of the precipitation increased.All above can provide a valuable result for the foundation of the Ground-based GPS , also it has a certain indication not only for the artificial precipitation but for predicting the precipitation which depends on the GPS data...