Determination of the velocity vector of Schirmacher glacier (Dronning Maud Land, Antarctica) using global positioning system

Abstract

Global Positioning System (GPS) has proved to be one of the most effective methods to measure glacier velocity. To give insight into the kinematics and quantitative understanding of the Schirmacher glacier (central Dronning Maud Land, Antarctica), two GPS campaigns were made during the austral summers of 2003 and 2004. GPS data were collected at 21 sites and have been analysed to estimate the site co-ordinates, baselines and velocities in ITRF2000. All the GPS points in the glacier have been constrained with the base station established at MAITRI, the Indian Antarctic Research Station and the nearby IGS stations, viz. VESL and SYOG. Displacement measurements were made from the GPS sites in Schirmacher glacier, parallel to the Schirmacher Oasis. The velocity of the sites is found to lie between 2 - 11 m yr-1 in NNE direction and the average velocity of the ice stream over the study region is 6.2 m yr-1. The site velocity distribution is spatially correlated to the surface undulation gradients, crevasses, and blockage of Schirmacher Oasis. In this paper, we report the glacier velocity vector derived from GPS and dynamic nature of the Schirmacher glacier.