3. Sentinel-1 InSAR Data for the Continuous Monitoring of Ground Deformation and Infrastructures at Regional Scale

A continuous monitoring system of ground deformation, based on radar images acquired by ESA (European Space Agency) Sentinel-1 constellation, is active over the Tuscany Region (Central Italy). The potential of repeat-pass satellite SAR (Synthetic Aperture Radar) interferometry has been exploited to investigate spatial patterns and temporal evolution of regional and local ground deformation that affect man-made infrastructures. With one million of points for each geometry of acquisition, ground deformation maps for Tuscany Region provide information that can be exploited to scan wide areas and to flag ground instabilities. These areas become targets for detailed analysis with high-resolution sensors (e.g., COSMO-SkyMed satellites of the Italian Space Agency) to create a virtual constellation, in which different satellite data sources are synergically used to create a more effective and robust Earth observation system. The results obtained are presented and discussed through the case studies of Pistoia and Guasticce (Livorno), where land subsidence threatens linear and areal strategic infrastructures. The examples highlight the capability of radar satellite missions to provide regularly spatially continuous information, which are of fundamental importance for monitoring ground deformation caused by land subsidence.