A NEW HIGH-RESOLUTION ELEVATION MODEL OF GREENLAND DERIVED FROM TANDEM-X

Under the right topographic and hydrological conditions, lakes may form beneath the large ice sheets. Some of these subglacial lakes are active, meaning that they periodically drain and refill. When a subglacial lake drains rapidly, it may cause the ice surface above to collapse, and here we investigate how to improve the monitoring of active subglacial lakes in Greenland by monitoring how their associated collapse basins change over time.

We present a new digital elevation model (DEM) of Antarctica derived from the TanDEM-X DEM, with new interferometric radar acquisitions incorporated and edited elevations, especially at the coast. A strength of this DEM is its homogeneity and completeness. Extensive validation work shows a vertical accuracy of just -0.3 m ± 2.5 m standard deviation on blue ice surfaces compared to ICESat laser altimeter heights. The new TanDEM-X PolarDEM 90 m of Antarctica is freely available.