STATIC GPS OBSERVATIONS ON THE ANTARCTIC PLATEAU FOR MOVEMENT DETECTION AND METEREOLOGICAL PURPOSES

Starting from the past decades geodetic community has paid increasing attention to the use of long time series coming from geodetic techniques; nowadays, Very Long Baseline Interferometry, GPS, Satellite Laser Ranging, DORIS are routinely used for measuring global geodynamics. In Antarctica the deployment of permanent and/or semi-permanent instruments in inaccessible regions (E.G. the Antarctic plateau), is strongly constrained by environmental conditions and logistics; as a result, control networks are frequently characterized by a campaign-style repetitions of measurements. With the aim to study the velocities of the ice, whenever speeds are at few cm/y level, it is necessary to be able to discriminate between relative movements due to the local morphology and those absolute induced from the tectonic effects of continental drift. Long-term GPS data acquisitions on the Antarctic plateau are rare, but they are quite useful for the connection between the local control networks and the global reference frame; the GPS strain networks installed around the deep ice coring sites at Dome C (DC, EPICA Project) and Talos Dome (TD, TALDICE Project) can be cited as examples Moreover in the framework of the Italian contribution to the ITASE Project, several GPS static sessions were acquired on the Antarctic plateau in order to realize control networks for ice surface monitoring, reference stations for geophysical prospecting, etc. (Frezzotti et al. 2004; Vittuari et al. 2004). We analyse here the feasibility to use these short GPS time series, characterised by continuous acquisitions recorded on periods of some weeks or few months and we point out our attention in order to evaluate, day by day along with time series, the stability in positioning and moreover, the estimation of tropospheric parameters. Corresponding author: luca.vittuari@mail.ing.unibo.it