Measure of the glacier movement speed

Images taken by Formosat over Kronebreen glacier near Ny Alesund in Svalbard, Norway. The animation enables to see the flow of the glacier. Using automatic image matching, it is possible to measure the movement of the glacier and thus to estimate the speed of the flow. This technique, already used with SPOT5 images [Berthier, Vadon et al., 2005], is here used with Formosat-2 images. Due to the observation with constant viewing angle, the image distorsion due to topography disappears: the accuracy of the glacier speed estimate obtained by sensors such as Formosat-2 and Venµs, is much better than the one obtained when the viewing angles change.

Comparison of surface speed (meters/year) of Kronebreen glacier (low noise area) in Svalbard, from May 1st to June 14th 2007 on the left and from June 26th to August 2nd 2007 on the right. The summer acceleration is particularly visible. Formosat-2 Images. Analysis: Etienne Berthier, Legos.