Monitoring Atmospheric Moisture Using GPS Precipitable Water Vapor

This article is aimed at indicating correlation between climatic changes and atmospheric moisture and precipitation using GPS precipitable water vapor values (PWV) and meteorological data in Khon Kaen, Thailand. PWV, average temperature, and precipitation data from 2001 to 2014 were analyzed to determine the changes over the time period. The estimation showed the average, maximum and minimum values of PWV in Khon Kaen at 48.42, 69.88, and 11.23 mm, respectively, with the standard deviation of 13.42 mm. Additionally, there was an increasing trend of PWV changes following temperature changes which could be due to the warm atmospheric properties that can hold vapor better than dry atmosphere. Again, at high temperatures, water in the environment vaporizes more easily than at low temperatures. However, precipitation tends to decrease which could be due to topographical condition of Khon Kaen which is on a high plain surrounded by mountains. As a result, monsoon wind is not able to bring moisture into the area. Therefore, the slightly increasing moisture cannot be a major cause of precipitation similar to a storm.