Detection of glaciers displacement time-series using SAR

Error sources and guidelines for quality assessment of glacier area, elevation change, and velocity products derived from satellite data in the Glaciers_cci project

“…For SAR sensors, estimates using very large window sizes (e.g., 512 x 512 pixels) are generally more precise for large structures, but are not applicable to small (e.g., < 500 m width) glaciers, nor do they provide information in shear zones (Strozzi et al, 2002;Paul et al, 2015). This drawback can be overcome by using iterative algorithms with a variable matching window size (Debella-Gilo and Nagler et al, 2015;Euillades et al, 2016). For optical sensors, these window sizes are typically 10-30 pixels wide, and in general, larger window sizes produce better accuracy for large structures, though the same drawback applies.…”

Towards monitoring groundwater‐dependent ecosystems using synthetic aperture radar imagery

“…The first generation of synthetic aperture radar (SAR) data became available in the 1990s and since then, it was applied in found applications in land cover mapping (e.g., Waske & Braun, ), wetland characterisation (Floyd et al, ; Touzi et al, ), fire hazard monitoring (e.g., Rykhus & Lu, ), sediment transport monitoring (e.g., Roering et al, ), landslide hazard monitoring (Scaioni et al, ), earthquake characterisation (e.g., Fujiwara et al, ), volcano monitoring (e.g., Brothelande et al, ), mangrove monitoring (e.g., Jaramillo et al, ), glacier displacement sensing (e.g., Euillades et al, ), groundwater extraction (e.g., Castellazzi et al, , , ), or oil‐spill detection (e.g., Fiscella et al, ). Most of these applications are now deployable operationally, thanks to the maturity of processing strategies, the development of freely available processing tools, the availability of archive datasets to establish baseline observations and infer change‐detection thresholds, and finally, the guarantee of frequent and regular future SAR acquisitions.…”

Quantitative Assessment of Digital Image Correlation Methods to Detect and Monitor Surface Displacements of Large Slope Instabilities

“…DIC, also known as feature-tracking or subpixel offset [15], is an image processing technique that identifies and quantifies ground displacement occurring orthogonal to the line-of-sight (LOS) of the camera [17]. Amongst others, DIC has been applied to monitor the glacier velocities [18,19], the ground displacement caused by earthquakes or tectonic activity [17,20], and the deformations at volcanoes [21]. A selection of application examples for DIC is listed in Table 1.…”