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Permafrost distributed in northeast China is the only high-altitude permafrost in China. The deformation monitoring over this permafrost region is of great importance to local climate change and ecological environments. This study focuses on the deformation monitoring of high-latitude permafrost in northeast China with time series InSAR technique. The spatial distribution characteristics, the annual deformation rates and the temporal deformation evolutions of permafrost could be retrieved from multi-temporal InSAR processing with Sentinel-1 TOPS datasets. This work concludes that time series InSAR technique could help to retrieve a comprehensive and reliable permafrost deformation, while a long time-series of displacements facilitated to better understand permafrost kinematics.

In China, landslides are widely distributed in the mountainous areas of western regions. Especially after the Wenchuan Earthquake in 2008, a large number of landslides were triggered. This work focuses on the deformation monitoring of Xishancun Landslide based on multi-platform spaceborne radar remote sensing techniques. The spatio-temporal deformation characteristics of landslide could be retrieved from time series InSAR processing with joint use of Sentinel-1 and TerraSAR-X datasets. Eventually, the deformation and evolution histories are cultivated thoroughly to realize an effective and comprehensive monitoring and research of Xishancun Landslide. This work concludes that spaceborne radar remote sensing applications could demonstrate great potentials to identify the spatio-temporal characteristics and investigate the kinematics for hazardous landslides, especially combined with in situ measurements and other remote sensing observations.

Early detection of landslides is important for disaster prevention, which was still very hard work with traditional surveying methods. Interferometric Synthetic Aperture Radar (InSAR) technology provided us the ability to monitor displacements along the slope with wide coverage and high accuracy. In this paper, we proposed a qualitatively multi-baseline DInSAR method to early detect and map the potential landslides. Two sections of China National Highway 317 and 213 were selected as study area. With this method 10 potential landslide areas were early detected and mapped in a quick and effective way. One of them (i.e. Shidaguan landslide) collapsed on August 2017, which was coincident with our results, suggesting that this method could become an effective way to acquire the landslide early detection map to assist the future disaster prevention work.

In this paper, we tried to reveal the characteristics of the crustal deformation in both the horizontal and vertical directions in Beijing using InSAR and GNSS observations. Regarding the serious land subsidence in Beijing plain, we also analysed the mechanism of the occurrence and development of the subsidence in combination with the tectonic settings. The GNSS results reveal that the crust in Beijing shows a significant left-lateral trend movement in the horizontal direction, while the vertical direction shows a gentle rise in the mountainous region and a significant subsidence in the plain area. The INSAR results shows a detailed subsidence area and the deformation characteristics were analyzed considering the fault activity. The foundation of geological structure dominates the subsiding in the Beijing Plain. The exploitation of groundwater exacerbates the level of subsidence and has new development. The active faults controlled the development of the subsiding in present days.

To extremely eliminate atmospheric delays for improving the accuracy of persistent scatter InSAR, the algorithm for constructing three-dimensional Delaunay network of global positioning system (GPS) stations is introduced to construct three-dimensional persistent scatter Delaunay network. The comparison with two-dimensional persistent scatter network indicates that three-dimensional Delaunay network is stable and avoids the affect of landscape conversion from geography space to image space. The urban subsidence of Lujiazui in Shanghai during 1992–2002 was effectively detected with InSAR based on three-dimensional persistent scatter Delaunay network. The result shows that persistent scatter InSAR based on three-dimensional persistent scatter Delaunay network can be used to efficiently and accurately detect ground deformation. The comparison with Leveling and InSAR based on persistent scatter planar network indicates that the accuracy and reliability of InSAR based on three-dimensional persistent scatter Delaunay network are significantly improved.