Paper Info
Title
Improved Ice Velocity Measurements with Sentinel-1 TOPS Interferometry.
Abstract
In recent years, the Sentinel-1 satellites have provided a data archive of unprecedented volume, delivering C-band Synthetic Aperture Radar (SAR) acquisitions over most of the polar ice sheets with a repeat-pass period of 6-12 days using Interferometric Wide swath (IW) imagery acquired in Terrain Observation by Progressive Scans (TOPS) mode. Due to the added complexity of TOPS-mode interferometric processing, however, Sentinel-1 ice velocity measurements currently rely exclusively on amplitude offset tracking, which generates measurements of substantially lower accuracy and spatial resolution than would be possible with Differential SAR Interferometry (DInSAR). The main difficulty associated with TOPS interferometry lies in the spatially variable azimuth phase contribution arising from along-track motion within the scene. We present a Sentinel-1 interferometric processing chain, which reduces the azimuth coupling to the line-of-sight phase signal through a spatially adaptive coregistration refinement incorporating azimuth velocity measurements. The latter are based on available ice velocity mosaics, optionally supplemented by Burst-Overlap Multi-Aperture Interferometry. The DInSAR processing chain is demonstrated for a large drainage basin in Northeast Greenland, encompassing the Northeast Greenland Ice Stream (NEGIS), and integrated with state-of-the-art offset tracking measurements. In the ice sheet interior, the combined DInSAR and offset tracking ice velocity product provides a spatial resolution of50x50mand 1-sigma accuracies of 0.18 and 0.44 m/y in the x and y components respectively, compared to GPS.
Year
DOI
Venue
2020
10.3390/rs12122014
REMOTE SENSING
Keywords
DocType
Volume
ice velocity,Greenland ice sheet,Sentinel-1,TOPS,DInSAR
Journal
12
Issue
Citations 
PageRank 
12
0
0.34
References 
Authors
0
5
Name
Order
Citations
PageRank
Jonas K. Andersen100.34
Anders Kusk2298.31
J. P. M. Boncori322.56
Christine S. Hvidberg400.68
Aslak Grinsted500.68