Land subsidence monitoring with differential SAR interferometry

The potential of differential SAR interferometry for land subsidence monito ring is reported on. The principle of the technique and the approach to be used on a specific case are first presented. Then significant results using SAR data from the ERS satellites for various sites in Germany, Mexico, and Italy, representing fast (m/year) to slow (mm/year) deformation velocities , are discussed. The SAR interferometric displacement maps are validated wi th available leveling data. The accuracy of the subsidence maps produced, t he huge SAR data archive starting in 1991, the expected continued availabil ity of SAR data, and the maturity of the required processing techniques lea d to the conclusion that differential SAR interferometry is suitable for op erational monitoring of land subsidence.