Using a global positioning system to estimate precipitable water vapor in Antarctica

The Global Positioning System (GPS) technology has become an essential tool in retrieving atmospheric precipitable water vapor (PWV) around the globe. This paper addressed the determination of GPS PWV in Antarctica and its response to atmospheric events. The GPS PWV result is then compared to the PWV determined from radiosonde (RS) and NCEP/NCAR Reanalysis. Time series comparisons of PWV between GPS and RS show strong linear correlation (R-2 =0.70, p < 1%) with their different mean values bounded at +/- 3 mm and with an RMS of 1.41 mm. Moreover, the total annual GPS PWV content at Scott Base, Casey, and Syowa stations averaged over the period from 2006 to 2008 has been quantified below 30 mm during summer polar days (wet summer) and of about 15 mm in winter polar night (dry winter), and their variability has shown a seasonal cycle dependence. One of the most remarkable features of the PWV variability from these regions carried by transient weather systems was that they closely followed the temperature patterns and revealed U-distribution. The temperature and PWV patterns characterize a coreless winter phenomenon.