Automatic Processing of Antarctic POLENET GPS Data

The Antarctica component of the NSF supported POLENET GPS network is an autonomous, continuously recording GPS network that sends GPS phase data files on a daily basis via satellite to the UNAVCO Facility (UF) Archive. The data are openly available from the UF Archive upon receipt. We have developed a system for automatically processing the continuous POLENET data available from the UF Archive. The results are preliminary, updated weekly, and made available as a community product on the POLENET website. The results provide an opportunity for identification of signals for more refined analysis, education and outreach, and a 'real-time' look at the operation of the network. We make use of GAMIT/GLOBK software package for basic GPS data processing and velocity estimation in the ITRF-05 Antarctica reference frame. The first POLENET GPS stations were installed during the 2007-2008 field season providing continuous time series up to three years length and we present preliminary displacement time-series and crustal velocities for 30 Antarctic POLENET GPS stations. The time series at the oldest sites are long enough to observe both secular and periodic vertical signals in the GPS time-series. The vertical signals are related to GIA, elastic response to secular and annual changes in ice mass, and seasonal atmospheric effects.