Topography and Penetration of the Greenland Ice Sheet Measured with Airborne SAR Interferometry

A digital elevation model (DEM) of the Geikie ice sap in East Greenland has been generated from interferometric C-band synthetic aperture radar (SAR) data acquired with the airborne EMISAR system. GPS surveyed radar reflectors and an airborne laser altimeter supplemented the experiment. The accuracy...

Full description

Bibliographic Details
Main Authors: Dall, Jørgen, Madsen, Søren Nørvang, Keller, K., Forsberg, René
Format: Article in Journal/Newspaper
Language:English
Published: 2001
Subjects:
Online Access:https://orbit.dtu.dk/en/publications/93797e48-6c50-4d98-808e-5755e907fe47
Description
Summary:A digital elevation model (DEM) of the Geikie ice sap in East Greenland has been generated from interferometric C-band synthetic aperture radar (SAR) data acquired with the airborne EMISAR system. GPS surveyed radar reflectors and an airborne laser altimeter supplemented the experiment. The accuracy of the SAR DEM is about 1.5 m. The mean difference between the laser heights and the SAR heights changes from 0 m in the soaked zone to a maximum of 13 m in the percolation zone. This is explained by the fact that the snow in the soaked zone contains liquid water which attenuates the radar signals, while the transparency of the firn in the percolation zone makes volume scattering dominate at the higher elevations. For the first time, the effective penetration has been measured directly as the difference between the interferometric heights and reference heights obtained with GPS and laser altimetry.