Correlation between precipitable water and rainfall using Global Positioning System (GPS) technique

We present the approach to remote sensing of water vapor based on the Global Positioning System (GPS). Signals propagating from GPS satellites to ground-based GPS receivers are delayed by atmospheric water vapor. Given surface meteorological measurements, this delay can be transformed into an estimate of the precipitable water overlying that receiver. We validate GPS precipitable water at rabt station with National Center for Environmental Prediction (NCEP) measurements. We show short-term correlation between GPS and rainfall during two different seasons, and we describe GPS tropospheric water vapor tomography, which could be utilized in operational weather forecasting and in fundamental research into atmospheric storm systems, the hydrologic cycle, atmospheric chemistry, and global climate change (severe events particularly).