Integrated use of InSAR and GNSS techniques for ground deformation monitoring

Understanding and monitoring the dynamics of the Earth’s surface is essential for scientific research, risk management, and sustainable land-use planning. Ground movements, whether natural or anthropogenic, including subsidence, landslides, tectonic uplift, and infrastructure-induced deformations, can significantly affect human settlements and critical infrastructure. This dissertation advances ground deformation monitoring through three complementary research themes. The first concerns the integration of Interferometric Synthetic Aperture Radar (InSAR) and Global Navigation Satellite Systems (GNSS), combining the dense spatial coverage of InSAR with the temporal continuity and reference accuracy of GNSS. Their joint use enables geophysically consistent deformation fields across multiple scales. The proposed framework was tested in Concepción (Chile) and extended to the Emilia Romagna region (Italy), demonstrating the effectiveness of integrated approaches for regional calibration and territorial management. The second theme focuses on the development of tools for advanced InSAR time-series analysis, designed to characterize both linear and periodic deformation components. The TimeSAPS software, developed within this research, decomposes InSAR signals to detect subtle nonlinear and seasonal patterns, improving the interpretation of local processes such as structural responses or subsurface fluid movements. The third theme addresses the usability of InSAR data through the creation of InSAR suitability indices, which combine parameters of data quality, coherence, and geometry to identify areas that can be reliably monitored using radar interferometry. Together, these three research directions, integration, methodological innovation, and usability assessment, provide a comprehensive framework for precise and operational ground deformation monitoring, supporting hazard assessment, infrastructure management, and sustainable territorial planning.