Multi-temporal SAR Interferometry (MTInSAR) techniques allow detecting and monitoring millimetric displacements occurring on selected point targets exhibiting coherent radar backscattering properties. Successful applications to different geophysical phenomena have been already demonstrated in literature. During the last several years new application opportunities have emerged thanks to the greater data availability offered by recent launches of radar satellites, and the improved capabilities of the new space radar sensors in terms of both resolution and revisit time. Currently, different space-borne SAR data in L-,C- and X-band are available for InSAR applications. The archived data from the European Space Agency (ESA) missions ERS-1/2 and ENVISAT (ENV) acquired in C-band (about 5 cm of wavelength), at medium resolution (5x20 m2) from 1992 to 2011 make available a large number (more than 40) of images covering more then 10 years with a minimum revisit time of 35 days, which allows performing ground instability analysis back in time almost all over the Earth. ESA Sentilnel-1 constellation will provide the continuity of the C-band SAR operational applications from October 2014. Thanks to the technological maturity as well as to the wide availability of SAR data, MTInSAR can be used to support systems devoted to environmental monitoring and risk management. This work present results obtained in the framework of two projects: the CAR-SLIDE (Mapping and monitoring system for landslides forecast) project which is funded by MIUR (PON R&C 2007-2013) and ADF (Archiving Data Fusion) project, funded by the Italian Space Agency (Second ASI Call dedicated to SMEs). CAR-SLIDE is aimed at implementing an advanced diagnostic system capable to warn of and monitor landslide events along railway networks, by integrating in situ data detected from on board sophisticated innovative measuring systems, with Earth Observation (EO) techniques. In particular SAR interferometry is used to monitor landslide events. The CAR-SLIDE system is structured in a modular way and mainly consists of the following three subsystems (S/S): (1) railway infrastructure monitoring S/S (based on video inspection sensors, georadars, vibration measurement systems and track geometry measuring devices) ; (2) Environmental Monitoring system (based on satellite SAR and optical data, and weather forecast provided by prognostic non-hydrostatic numerical mesoscale models); (3) Support Decision System (SSD). All measurements provided by the respective monitoring systems are integrated into the SSD, with the aim of improving the railway transport security management, by extending the concept of “black-box for alarm generation” to the actual idea of “telemetry for security management”. The goal of the ADF project is to design an innovative system for EO data acquisition, processing, fusion and archiving to support public institutions and private companies involved in emergency management, territorial planning and precise farming. The system has the capability to interface with many EO (SAR and optical) and traditional data sources and archives, thus enabling their selection and processing on demand, and to perform data fusion of EO data with ancillary data (INSPIRE, OpenStreetMap, etc.), with a high level of automatism. Concerning emergency management, data fusion techniques of SAR and optical data, together with land cover maps and digital terrain models are used to provide a priori estimations of Persistent Scatterers density along different line-of-sights, look sides and pass directions. We presents results obtained by processing COSMO-SkyMed satellite data acquired over Calabria region (Southern Italy) and Liguria region (Northern Italy). The first test case shows interesting results concerning the Calabria's Tyrrhenian railway line, classified as fundamental line by the Italian Rail Network and belonging to the Trans-European Transport Network. Moreover, it provides another interesting example of infrastructure monitoring concerning the “Giambarelli” viaduct along the A3 highway close to the Barritteri town. The second example consists in a retrospective analysis on the detection of precursory signals related to the landslide which occurred on January 2014 close to the town of Marina di Andora. The landslide caused the derailment of a train and the interruption of the railway line connecting north-western Italy to France. We show that a cluster of moving targets coincides with the structures (buildings and terraces) affected by the 2014 landslide. The analysis of the MTI time series further shows that the targets had been moving since 2009, and thus could have provided a forewarning signal about ongoing slope or engineering structure instability. Further examples, concerning the suitability of MTInSAR techniques and high-resolution SAR sensors for man-made structures stability over the Genoa metropolitan and surrounding areas, are also presented and discussed.
|Titolo:||Exploitation of Multi-Temporal SAR Interferometry for systems devoted to Environmental Monitoring and Risk Management|
|Data di pubblicazione:||2015|
|Nome del convegno:||Fringe 2015 Workshop Advances in the Science and Applications of SAR Interferometry and Sentinel-1 InSAR Workshop|
|Appare nelle tipologie:||4.2 Abstract in Atti di convegno|