Comparison of groundwater induced Land subsidence in London and Delhi using PSInSAR

Unrestrained urbanisation and rapid land use land cover changes can impact underlying aquifer systems, resulting in the instances of land subsidence. Thus, monitoring of groundwater induced land movement is an important part of environmental information systems and helps maintain the safety and economics of a city. Interferometric Synthetic Aperture Radar (InSAR) can facilitate monitoring of land movement and observed boreholes can facilitate groundwater monitoring. In this study, we used Sentinel-1 radar images to obtain land movement using Persistent Scatterer InSAR (PSInSAR) technique in the ENVI SARscape software package. The land movement has been studied between October 2016 and October 2020, using 98 SAR images for Delhi and 100 SAR images for London. This is the first time that such a comparison has been made between these two great cities.