|Paper title||Regional scale monitoring results of surface deformation in the GeoSES Project focusing to the Transcarpathian Region|
|Form of presentation||Poster|
One of the main objectives of the GeoSES* project to monitor dangerous natural and anthropogenic geo-processes, using space geodetic technologies and concentrating on the Hungary-Slovakia-Romania-Ukraine cross-border region. The prevention and monitoring of natural hazards and emergency situations (e.g. landslides, sinkholes or river erosion) are also additional objectives of the project. According this, integration advanced remote sensing techniques in a coordinated and innovative way leads to improve our understanding of land deformation and its impact on the environment in the described research area. In the framework of the presented project, our study utilizes one of the fastest developing space-borne remote sensing technology, namely InSAR, which is an outstanding tool to perform large scale ground deformation observation and monitoring. Performing such monitoring task, we utilized ascending and descending Sentinel-1 Level-1 SLC acquisitions since 2014 until 2021 over the indicated cross-border region.
We also present an automated processing chain of Sentinel-1 interferometric wide mode acquisitions to generate long-term ground deformation data. The pre-processing part of the workflow includes the migration of the input data from the Alaska Satellite Facility (ASF), the integration of precise orbits from S1QC, the corresponding radiometric calibration and mosaicing of the TOPS mode data, as well as the geocoding of the geometrical reference. Subsequently all slave acquisition have be co-registered to the geometrical reference using iterative intensity matching and spectral diversity methods, as well as subsequent deramping has been also performed. To retrieve deformation time series from co-registered SLCs stacks, we have performed multi-reference Interferometric Point Target Analysis (IPTA) using singe-look and multi-look phases using the GAMMA Software. After forming differential interferometric point stacks, we performed the IPTA processing. According this both topographical and orbit-related phase component, as well as the atmospheric phase, height-dependent atmospheric phase and linear phase term supplemented with the deformation phase are modeled and refined through iterative steps. The proposed pipeline also supported by an automatic phase unwrapping error detection method, such aims to detect layers in the multi-reference stack which are significantly affected by unwrapping errors. To retrieve recent deformations of the investigated area, SVD LSQ optimization has been utilized to transform the multi-reference stack to single-reference phase time-series such could be converted to LOS displacements within the processing chain. Involving both ascending and descending LOS solutions also supports the evaluation of quasi East-West and Up-Down components of the surface deformations. The derived results are interpreted both in regional scale and through local examples of the introduced cross-border region as well, as aiming the dissemination of the InSAR monitoring results of the GeoSES project.
* Hungary-Slovakia-Romania-Ukraine (HU-SK-RO-UA) ENI Cross-border Cooperation Programme (2014-2020) “GeoSES” - Extension ofthe operational "Space Emergency System"