Study on Groundwater and Deformation Time Series From ASAR And Terrasar-X Using Short Baseline Tcpinsar and in-Situ Measurements in Shanghai

For delta area once groundwater is over-exploited, it may trigger a series of geological disasters, especially ground subsidence, which made the city along coastal regions have an increased risk of sea-level rise. During recent years at Yangtze Delta ground subsidence has got been controlled primarily via re-pumping of seawater into land region, but the subsidence is still continuous. TCPInSAR(Temporarily Coherent Point Synthetic Aperture Radar Interferometry) technique as an improvement of PSInSAR can generate the settlement time series with high accuracy. We adopted this technique to process ENVISAT ASAR images spanning from 2007 to 2009 and TerraSAR-X images spanning from 2009 to 2010 to obtain the land surface subsidence in Shanghai. And then we compared the settlement of this area with the groundwater level measured by the in-situ wells, and found the two are in good agreement. Finally, we estimated the storage coefficients of the aquifer. This study showed that InSAR technique is very useful to monitor and model groundwater efficiently.