Mapping Land Subsidence in Urban Areas Using Esa’s G-POD and the P-SBAS Insar Technique: Examples in Asia, South America And North Africa

Ground stability and surface deformation in the urban areas of Zhengzhou (China), Osaka and Kyoto (Japan), Bogotá (Colombia) and Tunis (Tunisia) are investigated using satellite Interferometric Synthetic Aperture Radar (InSAR). The Parallel Small BAseline Subset (P-SBAS) workflow integrated within ESA’s Grid-Processing On Demand (G-POD) platform is used to process ENVISAT data. Distinctive land subsidence patterns are found in: suburban zones and new urban developments in Zhengzhou (-40 mm/year LOS rates), along the coastline of the Osaka Bay, onto the Yodo River alluvium (-28 mm/year), in the city of Bogotá and the Sabana de Bogotá basin (-44 mm/year), and the low-lying area of Tunis Marine and the shores of Tunis Lake (-20 mm/year). Most of these patterns are due to groundwater pumping for domestic, industrial and agricultural use, or sediment compaction after coastal reclamation and drainage for new urbanization.