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The thickness estimation of landslides is crucial for better landslide evaluation. Traditional non-contact mass conservation methods using 3D deformation may be unsuitable due to observation limitations. This study proposes a more feasible approach based on 2D deformation from two-track Interferometric Synthetic Aperture Radar (InSAR) observations, applied to the Xiongba landslide. The comparison with geological and drilling measurements confirms the reliability of this method. The mapped InSAR LOS deformation rate fields reveal two regions: a significantly deformed frontal zone and a relatively stable zone. Analysis suggests that surface uplift at the Xiongba-H2 landslide's front edge results from rock–soil mass pushing in high-deformation areas. The estimated thickness ranges from 10 to 100 m, with an active volume of 6.17 × 107 m3. A thicker region is identified at the front edge along the Jinsha River, posing the potential for further failure. This low-cost, easily implemented approach enhances InSAR's applicability for landslide analysis and hazard assessment. [ABSTRACT FROM AUTHOR]

Many major cities worldwide have inevitably experienced excessive groundwater pumping due to growing demands for freshwater in urban development. To mitigate land subsidence problems during urbanization, various regulations have been adopted to control groundwater usage. This study examines the transition in the post‐subsidence stage, especially in metropolitan areas, to adaptively adjust subsidence prevention strategies for effective groundwater management. Taking the Taipei Basin as an example, historical data reveals significant subsidence of more than 2 m during early urban development, with subsidence hazards largely mitigated over decades. However, the rising groundwater level poses a risk to the stability of engineering excavations. In this study, 29 X‐band Cosmo‐Skymed constellation (CSK) images were utilized with the Persistent Scatterer InSAR (PSInSAR/PSI) technique to monitor surface displacements during the construction of the Mass Rapid Transit system. Correlating groundwater levels helps identify the heterogeneous hydrogeological environment, and the potential groundwater capacity is assessed. PSI time‐series reveal that approximately 2 cm of recoverable land displacements correspond to groundwater fluctuations in the confined aquifer, indicative of the typically elastic behavior of the resilient aquifer system. The estimated groundwater storage variation is about 1.6 million cubic meters, suggesting this potential groundwater capacity could provide available water resources with proper management. Additionally, engineering excavation safety can be ensured with lowered groundwater levels. This study emphasizes the need to balance groundwater resource use with urban development by adjusting subsidence prevention and control strategies to achieve sustainable water management in the post‐subsidence stage. Plain Language Summary: Groundwater is used as an important freshwater resource in global urban development, but over‐exploitation often leads to subsidence problems. Once land subsidence situation is under controlled, attention turns to how to balance urban development with environmental protection. This study takes a metropolitan area in a post‐subsidence period as an example and uses satellite technique to estimate potential groundwater volumes. It suggests that with proper management, groundwater resources can be fully utilized and related engineering disasters can be prevented. Key Points: Integrating InSAR and numerical model for transient‐like state groundwater level mappingQuantifying changes in potential groundwater storage as available freshwater resourcesEfficient groundwater utilization for achieving sustainability in post‐subsidence stages [ABSTRACT FROM AUTHOR]

Geodetically measured surface displacements are produced by a combination of underlying deformation processes acting at different spatial and temporal scales. A complete history of surface measurements in an area can help discriminate contributions from tectonic, hydrologic, and anthropogenic processes. In this study, we use Synthetic Aperture Radar (SAR) images of the active mountain front and adjacent coastal plain of southwestern Taiwan to generate time series of surface deformation from 1995 to 2001 and from 2005 to 2008 based on the InSAR small baseline method. The InSAR measurements agree well with LOS motions estimated from continuous GPS measurements of 3D displacements between 2006 and 2008. A significant range increase in line of sight (LOS) is dominated by land subsidence in the coastal area of western and southwestern Taiwan. Subsidence rates vary with annual periods and are highly correlated with seasonal precipitation, which are likely associated with groundwater recharge and withdrawal. The long-term deformation is dominated by long-term tectonic loading in SW Taiwan during the interseismic period of the earthquake cycle, including elastic strain along or continuous creep on the active faults. Our results show the ability of InSAR to reveal spatiotemporal crustal deformation in western Taiwan with high spatial resolution and accuracy, which is potentially important for evaluating seismic hazards.