Glacier Velocity Determination from Multi Temporal Terrestrial Long Range Laser Scanner Point Clouds

Research on the motion behaviour of arctic glaciers provides important information about the influence of global temperature changes on the climate system and especially the global sea level rise. In the past years dramatic changes could be observed for some of the Greenland outlet glaciers. Jacobshavn Isbrae is one of the fastest and most productive glaciers in Greenland and is therefore an interesting research object. The paper presents a new technique for the determination of 3D glacier surface velocity fields, which is based on processing multi-temporal terrestrial long range laser scanner data. Multi-temporal 3D point clouds were acquired by a long range terrestrial laser scanner Riegl LPM-321, which offers a maximum range of 4 km when measuring on glacier ice. Velocity vectors are determined by applying 2D matching techniques to the point clouds interpolated to a regular grid. The paper also proposes solutions for the determination and elimination of angular errors which occurred in the data. The results show that terrestrial long range laser scanning is a suitable tool for the determination of high-resolution velocity fields of glaciers.