High Resolution PSI for Mapping Ground Deformations and Infrastructure Instability

Persistent scatterers interferometry (PSI) based on space-borne radar data can provide thousands km2 coverage and precise (mm resolution), spatially dense measurements (from hundreds to over thousands points/km2) on ground deformations and infrastructure instability. Furthermore, the practical applicability of PSI is now improved thanks to the increased data availability and the better capabilities of the new space radar sensors (Cosmo-SkyMed, TerraSAR-X) in terms of resolution (from*3 to 1 m) and revisit time (from 11 to 4 days). We compare results from medium and high resolution PSI investigations of subsidence, slope and associated infrastructure instability in two areas with different geo-environmental characteristics to illustrate (i) the potential in providing site-specific information, (ii) the advantages of high resolution radar data. We also focus on technical and interpretation issues in PSI applications and offer specific user guidelines, with emphasis on the benefits resulting from the exploitation of new generation radar sensors.