Terra Nova Bay GPS permanent station (Antarctica): data quality and first attempt in the evaluation of regional displacement

The paper discusses the long time series analysis of GPS permanent station located at Terra Nova Bay, East Antarctica (Victoria Land). The station (TNB1) was monumented during the 1997–1998 Italian expedition in Antarctica and the data collection started on January 1998. TNB1 is included in the Victoria Land network for deformation control (VLNDEF) network that was established with the aim to study the horizontal and vertical displacements in the region. The good-quality data obtained from this station allow the computation of long time series performed both by using a network approach with Bernese V4.2, and precise point positioning technique with GIPSY–OASIS II. In a first step, a subset of data was analysed to define the best processing strategy. Moreover, in the network approach, international GPS service (IGS) permanent stations (intra- and extra-plate) were used. Results obtained from the two approaches are comparable in terms of both repeatability and linear trend. Finally, velocities estimated for all Antarctic stations were compared to the values provided by ITRF2000. In most cases horizontal velocities agree with the model, while significant differences are present along the vertical components.