1. Ice velocity determined using conventional and multiple-aperture InSAR
- Author
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Finnur Pálsson, Aud Venke Sundal, Noel Gourmelen, Sang-Wan Kim, Andrew Shepherd, Helgi Björnsson, and J. Park
- Subjects
010504 meteorology & atmospheric sciences ,Aperture ,Ice stream ,0211 other engineering and technologies ,02 engineering and technology ,Tracking (particle physics) ,01 natural sciences ,Displacement (vector) ,Physics::Geophysics ,Speckle pattern ,Geochemistry and Petrology ,Interferometric synthetic aperture radar ,Earth and Planetary Sciences (miscellaneous) ,Surge ,Physics::Atmospheric and Oceanic Physics ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Remote sensing ,geography ,geography.geographical_feature_category ,Glacier ,Geodesy ,Geophysics ,Space and Planetary Science ,Astrophysics::Earth and Planetary Astrophysics ,Geology - Abstract
We combine conventional Interferometric Synthetic Aperture Radar (InSAR) and Multiple Aperture InSAR (MAI) to determine the ice surface velocity on the Langjokull and Hofsjokull ice caps in Iceland in 1994. This approach allows the velocity of the 20 principal ice cap outlet glaciers to be fully resolved. We show that MAI leads to displacement estimates of finer resolution (15 versus 150 m) and superior precision (5 versus 15 cm) to those afforded by the alternative technique of speckle tracking. Using SAR data acquired in ascending and descending orbits, we show that ice flows within 15° of the direction of maximum surface slope across 66% of the ice caps. It is therefore possible to determine ice displacement over the majority of the ice caps using a single SAR image pair, thereby reducing errors associated with temporal fluctuations in ice flow.
- Published
- 2011
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