Monitoring unstable slopes using Persistent Scatterers Interferometry: opportunities and challenges

Advanced space-borne Persistant Scatterers Interferometry (PSI) can provide wide-area coverage (thousands km(2)) and precise (mm-cm resolution), spatially dense information (from hundreds to over thousand measurement points/km(2)) on ground surface deformations. Furthermore, new application opportunities are emerging thanks to i) the greater data availability offered by recent launches of radar satellites, ii) the improved capabilities of the new space radar sensors (Cosmo-SkyMed, TerraSAR-X) in terms of resolution (from 3 to 1m) and revisit time (from 11 to 4 days). Although, the applicability of radar interferometry to regional and local-scale investigations of slope instability have been demonstrated in several studies, more progress is needed in the integration of PSI results with ground data and in their validation in order to foster a more profitable use of this technique. It is also expected that numerical modeling slope deformations detected by radar satellites should help to constrain the data interpretation.