Diurnal variation of atmospheric water vapor based onGPS observations over Taiwan

摘要

Diurnal variations in the atmospheric vapor atrnBanchiao of Taiwan are studied by analyzing 30 min-averagedrndata in the summer of 1998. The surface meteorologicalrnmeasurements were mainly obtained from the Central WeatherrnBureau (CWB) of Taiwan. It is found that precipitable waterrn(PW) is increased in the afternoon. The maximum ofrnprecipitable water appears at around 0900 LST. The diurnalrnrange of precipitable water is larger on the days with thanrnwithout rainfall events. Rainfall events often occur in thernafternoon and early morning. We also examine the differencernin the characteristics of the PW signatures with and withoutrnrainfall according to the occurrence of the times for the rainfallrnpeak and the onset of rainfall.