Measurement of Ground Subsidence in Mokpo Area from Radar Intrerferometry

Mokpo city is a coastal city located at the south western coast of the Korean Peninsula. Large regions within Mokpo are subjected to significant subsidence because about 70% of the city area is a reclaimed land from the sea. Although no confidential quantitative measurements are available up to the present, the subsidence rate is as much as several cm per year. In this study, we aimed to estimate the subsidence rate over Mokpo city by using twentysix JERS-1 SAR dataset from September 1992 to October 1998. Several tens of differential interferograms were processed from JERS-I dataset and STRM 3-arc DEM. The results indicate continuous subsidence in Dongmyungdong, Hadang-dong and Wonsan-dong in city, and the subsidence velocity reach over 4 cm/yr in the most highly sinking area. For facilitating the analysis of time-varying surface change, we also carried out an interferometric SAR time series analysis using permanent scatterer and consequently determined space-time maps of surface deformation at each acquisition time of JERS-1 SAR.