Terra Nova Bay GPS permanent station

During the IV Italian expedition in Antarctica, the geodetic activity started with the installation of the geodetic network in the area of Terra Nova Bay. The network was established in order to provide a common reference frame to several scientific activities (photogrammetry, cartography, geology) and to study the geodynamics of an area including some interesting tectonic and geologic features. The TNB1 (official name) GPS permanent station was installed during the XIII Italian expedition in 1998, over a granitic hill close to the Italian station of Terra Nova Bay. Following the recommendations for a stable and well-suited site location for the GPS permanent station a concrete-made pillar was monumented in an area far away from radio frequency disturbs which also guaranteed a complete satellite visibility. The location of the GPS permanent station site with respect to Terra Nova Bay station and a particular of the monumentation are shown in figure 1. The geographic location of Terra Nova Bay covered a gap in the distribution of GPS permanent stations in East Antarctica and, more precisely, along northern Victoria Land. Fifteen GPS permanent stations have been installed in Antarctica until today, and seven of them are IGS (International GPS Service for Geo-dynamics) stations. The non-homogeneous geographic distribution of stations, the long distances involved and their prevalent settlement on the coastal area leads to some difficulties in a precise satellite ephemeris determination and in GPS data processing for regional geodynamic purposes phenomena with an accuracy at the 5 mm level achieved in static relative positioning.