Development of Near Real-Time PWV Estimation System for Monitoring the Meteorological Events in Thailand

Abstract

Nowadays, Global Navigation Satellite System (GNSS) observation is widely used as an alternative approach to estimate the Precipitable Water Vapor (PWV). The process of Precise Point Position (PPP) is now well developed and commonly applied to process GNSS ground-based observations. This study developed the system to acquire data from 121 permanent reference stations of GNSS CORS spatially distributed across Thailand to analyze and monitor GNSS-PWV. Several other meteorological data like surface pressure, temperature, and humidity were collected from 478 telemetry stations. The developed system reduces the time for data processing, making the approach more promising for meteorological applications. The comparison of GNSS-PWV from CODE and IGS data correction shows an average correlation of 0.29. However, there is a potential for monitoring the meteorological phenomenon based on the analysis between near real-time GNSS-PWV and average rainfall rate for specific rainfall duration and a selected frequency called rainfall intensity in the central of Thailand during the severe rainfall events.