Global dataset of Sentinel-1 azimuth shift values and derived horizontal displacements from COMET LiCSAR system

For this dataset, we were exploiting spatio-temporal behaviour of side-products of coregistration of Sentinel-1 radar images, that were generated in last couple of years, within the COMET LiCSAR system for computing interferograms. These side-products are sub-pixel (azimuth) offsets, allowing for a very precise match of the images (up to a 0.0005 pixels). We have shown that by a proper approach, these offsets can be used as measurements of large-scale horizontal motion - in our case, using 250x250 km resolution cells, we aimed to measure motion of tectonic plates. Our measurements are fitting well to the latest ITRF2014 plate motion model, although the E component contains an extra overall shift, not explained at the moment of sharing the outputs.

The sub-pixel offsets (result of intensity cross correlation and spectral diversity estimation, w.r.t. precise orbit ephemerides) were corrected for solid Earth tides and ionospheric phase advance, using external models. The code shared within the dataset includes the correction functions. The data contains both original and corrected values. Also, the data contains ITRF2014 plate motion values.

The dataset contains outputs from both COMET LiCSAR frame units and their decomposition into N, E motion vectors, as well as some metadata on the frames that are necessary for the reprocessing if needed.