Multi-sensor InSAR analysis of surface displacement over coastal urban city of Trondheim

Abstract

In this study, we present maps of ground surface displacement of the coastal urban city of Trondheim in central Norway using observations from interferometry synthetic aperture radar (InSAR). We used 98 SAR images including 31 TerraSAR-X, 49 Radarsat-2, and 18 Sentinel-1 to assess mean deformation velocity maps and displacement time-series in the city between 2012 and 2016. We processed the data using InSAR time-series technique of Small BAseline Subset (SBAS) approach. The results show that the displacement with the maximum value of approximately -15 mm/yr has been happening on the coastal area since 2012. However, in the rest of the city displacement patterns vary in different time-periods. The displacement velocity in the city ranged from -10 to +2 mm/yr in 2012-2014, -4 to +2 mm/yr in 2012-2015, and -7 to +7 mm/yr in 2015–2016 in the line of sight (LOS) direction.