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The topic of this work covers current implementation of satellite radar (SAR) interferometry (InSAR) techniques for routine identification of dynamic land processes such as downhill creep and landslide activity, subsidence or displacements of various objects of infrastructure. With the emerge of European Copernicus programme, the need of effectivity in satellite Big Data processing increased. There are two Sentinel-1 satellites observing the Earth with 6 days revisit time, sending daily 100 TB of data to be archived. In case of the relatively small area of Czechia, the amount of data to be archived in a Czech national mirror is around 24 GB per day. Czech CESNET e-infrastructure has accepted the role of assessing Copernicus Ground Segment programme. A database mirroring Sentinel data over Czechia is established, however still in its early stage. A potential service based on an interferometric processing of Sentinel-1 data from this database has been prepared in Czech national supercomputing center IT4Innovations. As a basis of the system, several open-source projects were deployed, including MySQL-based burst metadatabase (TU Leeds), ISCE TOPS Processor (NASA/JPL), Doris coregistration algorithm (TU Delft) and StaMPS Small Baselines processor (Stanford University). Though more functionality can be rapidly developed, incorporating some of the own post-processing algorithms, even current early version of the system can yield interesting results by a fully automatic processing chain.

This short paper summarizes the effects of DEM errors influencing precision of deformation monitoring results using satellite SAR interferometry and presents basic mathematical approaches to quantify DEM accuracy needed for proper estimation of SAR interferometry parameters. While in case of appropriately large SAR dataset for Multi-Temporal Interferometry (MTI) processing the height difference is usually well estimated, still DEM accuracy should be carefully considered in case of using low number of images—and especially in case of processing differential InSAR with only one image pair. Depending on the interferogram pair combination characteristics, especially parameter known as perpendicular baseline (Bperp) describing the distance between satellite positions during their image acquisitions, the interferogram is more or less prone to DEM accuracy errors. In case of higher Bperp, a relatively high quality DEM is necessary to remove stereoscopic effect apparent in interferogram in order to distinguish interferogram phase element caused by temporal terrain deformation.