关键词: 地基 GPS, 大气可降水量, 特征, 突变分析

Abstract: Atmospheric precipitable water vapor (PWV) is an important factor affecting rainfall. Based on ground-based GPSretrieved PWV data, ground meteorological observations, sounding data and ERAInterim reanalysis data from 2010 to 2019, the seasonal, monthly and diurnal variation characteristics of water vapor resources over Fujian were analyzed. Moreover, the spatial and temporal characteristics of PWV were assessed by using the empirical orthogonal function (EOF), MannKendall test and the sliding t test. The results show that the accuracy of the groundbased PWV was higher compared with ERAInterim reanalysis data. The water vapor resource over Fujian was largest in summer, followed by spring, autumn and winter. The monthly distribution of PWV presented an inverted Ushaped, and the diurnal variation of PWV changed significantly on sunny day and rainy day. The PWV of the eastern coastal areas was generally higher than that of the western mountainous areas, but the precipitation conversion rate of PWVthere was lower than that of the inland mountainous areas. The first mode of EOF decomposition of PWV presented the main characteristics with a variance contribution rate of 80.06%. The eigenvalues were positive in the whole region, which indicated that the spatial change of PWV had good consistency. The oscillation intensity of PWVstrengthened from northwest and southwest to the east, and the corresponding time curve characterized the significant seasonal changes of PWV. The mutation test of MannKendall and the sliding t test showed that the water vapor resources over Fujian had not undergone abrupt change in the past 10 years.

Key words: ground-based GPS, precipitable water vapor (PWV), characteristics, mutation test