Land Subsidence Monitoring with Differential SAR Interferometry

Abstract

This article investigates whether differential synthetic aperture radar (SAR) interferometry can be used to monitor land subsidence. The principle of the technique and the approach used on a specific case are presented. The high potential of differential SAR interferometry to monitor a wide range of deformation velocities ranging from fast (m/year) to slow (mm/year) was demonstrated by the generation of subsidence maps for sites in Germany, Mexico, and Italy. The SAR interferometric displacement maps are validated with available leveling data. Differential SAR interferometry is suitable for operational monitoring of land subsidence due to the accuracy of the maps produced, the extensive SAR data archive over the past 10 years, the expected continued availability of SAR data, and the maturity of the required processing techniques. A strategy for the integration of leveling, global positioning systems, and SAR data is proposed in order to achieve an accurate, rational and cost-effective monitoring.