Analysis of water vapor characteristics of regional rainfall around Poyang Lake using ground-based GPS observations

Atmospheric precipitable water vapor of Poyang Lake area can be estimated using the ground-based global positioning system technology and the atmospheric precipitable water vapor change characteristics during the rainfall process can be analyzed. At the same time we can use National Centers for Environmental Prediction reanalysis data and high-density grid data analysis of weather system, water vapor transmission, convergence and precipitation power mechanism. The atmospheric precipitable water vapor and rainfall contrast analysis show that rainfall and precipitable water vapor are not directly in corresponding relation, and their values are not always mutually corresponded. The value of rainfall is closely related with the water vapor transfer and water vapor convergence. In front of the rainfall the increasing process of GPS/PWV changes continuously, and increases suddenly in about 1 h before the rainfall. The rainfall is not always smaller than the biggest value of GPS/PWV, and has the possibility to be bigger than the GPS/PWV values. GPS delivered PWV could be used to improve the near real time forecast/short term forecast of precipitation.