Acquisition of a 3 min, two-dimensional glacier velocity field with terrestrial radar interferometry

• Published in: Journal of Glaciology
• Main Authors: DENIS VOYTENKO, TIMOTHY H. DIXON, DAVID M. HOLLAND, RYAN CASSOTTO, IAN M. HOWAT, MARK A. FAHNESTOCK, MARTIN TRUFFER, SANTIAGO DE LA PEÑA
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press 2017
• Subjects: glacier flow; glacier geophysics; glaciological instruments and methods; Environmental sciences; GE1-350; Meteorology. Climatology; QC851-999; Jakobshavn; Journal of Glaciology
• Online Access: https://doi.org/10.1017/jog.2017.28; https://doaj.org/article/0200b593ecf44f5cb1f9452d13d92d80

Outlet glaciers undergo rapid spatial and temporal changes in flow velocity during calving events. Observing such changes requires both high temporal and high spatial resolution methods, something now possible with terrestrial radar interferometry. While a single such radar provides line-of-sight velocity, two radars define both components of the horizontal flow field. To assess the feasibility of obtaining the two-dimensional (2-D) flow field, we deployed two terrestrial radar interferometers at Jakobshavn Isbrae, a major outlet glacier on Greenland's west coast, in the summer of 2012. Here, we develop and demonstrate a method to combine the line-of-sight velocity data from two synchronized radars to produce a 2-D velocity field from a single (3 min) interferogram. Results are compared with the more traditional feature-tracking data obtained from the same radar, averaged over a longer period. We demonstrate the potential and limitations of this new dual-radar approach for obtaining high spatial and temporal resolution 2-D velocity fields at outlet glaciers.