Remote sensing of the atmosphere using Global Positioning Systems has been made possible with the derivation of the precipitable water vapor (PWV) from the tropospheric wet delay experienced by the signal propagation. Although limited by the missing observational data from the receiver, it is observed that the PWV obtained from this data gives reasonable values when considered for the cases of wet and dry seasons and when analyzed with a measurable meteorological variable such as the amount of rainfall. A continual update of the record for PWV is highly recommended for further studies on the behavior of the atmospheric water vapor and its contribution to the changing climate.
[Presented at the Samahang Pisika ng Pilipinas (SPP) Congress, 2001.]