Abstract
This paper characterizes the precipitable water vapor (PWV) variation derived from GPS measurements during two flood cases over Keningau, Sabah. Two years of GPS and meteorological data in 2008 and 2009 located at BEAU, UMSS, and LAB1 stations were processed and analyzed. Rainfall data taken at the same station was compared. Results showed that the rainfall in 2009 was observed 30 mm higher than the distribution in 2008. During 2008 event, PWV was reduced almost 2.0 mm when the difference in rainfall is exceeding 8 mm in all stations. During 2009 event, PWV variation and meteorology factors in the nearest stations do not affected by the rainfall in Keningau. In this case, the changes in PWV variability during flood event show that the meteorological parameters such as wind effects and seasonal change is expected contributes in the distribution of water vapor.