Potential of RADARSAT-2 stereo radargrammetry for the generation of glacier DEMs

• Published in: Journal of Glaciology
• Main Authors: PAPASODORO, C., ROYER, A., LANGLOIS, A., BERTHIER, E.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2016
• Subjects: Earth-Surface Processes; Barnes Ice Cap; glacier*; Ice cap; Journal of Glaciology; Nunavut
• Online Access: http://dx.doi.org/10.1017/jog.2016.44; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143016000447

ABSTRACT The study of glaciers and ice caps in remote and cloudy regions remains difficult using current remote sensing tools. Here the potential of stereo radargrammetry (SRG) with RADARSAT-2 Wide Ultra-Fine images is explored for DEM extraction, elevation changes and mass-balance calculations on Barnes Ice Cap (Nunavut, Canada). Over low-relief terrain surrounding Barnes, a vertical precision of ~7 m (1σ confidence level) is measured, as well as an average vertical bias of ~4 m. Moreover, we show that the C-band penetration depth over the ice cap is insignificant at this time of the year (i.e. late ablation season). This is likely due to a wet surface and the presence of superimposed ice that leads to a surface radar response. Comparing the SRG DEMs with other datasets, an historical glacier-wide mass balance of −0.52 ± 0.19 m w.e. a −1 is estimated for 1960–2013, whereas it decreases to −1.06 ± 0.84 m w.e. a −1 between 2005 and 2013. This clear acceleration of mass loss is in agreement with other recent studies. Given its all-weather functionality and its possible use without ground control points, the RADARSAT-2 SRG technology represents an appropriate alternative for glacier monitoring in cloudy and remote regions.