Atmospheric water vapor plays an important role for a better understanding of global climate changes and directly affects the potential amount of precipitation and accumulation of polar ice sheet. Antarctic water-vapor measurements are hard to obtain due to sparse number of research stations and extreme climate conditions. Out of this reason the Global Positioning System could be a cost-effective, weather-independent alternative to increase the number of Antarctic water vapor measurements. The main goal of the presented analysis is to validate the utility of ground-based GPS-measurements in comparing GPS-estimated water vapor values with results from standard measurement-types (e.g. Radionsonde, remote-sensing). The preliminary results show a correlation coefficient between radiosonde and GPS-based measurements of 0.89. Seasonal and spatial effects can also be observed in GPS PWV-time-series. All in all the results show that ground based GPS is a promising tool to measure atmospheric water vapour particularly in remote sensing areas where data from other sources is sparse.