Synergizing P/L/C-band SAR to monitor landslides along the U.S. west coast

Landslides are an important landscape shaper and pose a dangerous natural hazard around the globe. Effective monitoring of their kinematics is crucial for improving our understanding of how landslides respond to environmental forcing (e.g., precipitation, coastal erosion, and earthquakes), thereby helping generate insights to reduce their hazard. Towards this end, InSAR (Interferometric Synthetic Aperture Radar) has demonstrated to be a powerful tool for both landslide detection and temporal displacement monitoring. However, SAR sensors' capabilities for landslide surveying vary, depending on the sensor's operating wavelength, LOS (line of sight) direction, spatial resolution, revisiting time, and the environmental and geometric settings of the target landslides. Here, we utilize P/L-band UAVSAR, L-band ALOS-2, and C-band Sentinel-1 data to survey slow-moving landslides along the U.S. west coast, and comprehensively explore these SAR systems' variable capabilities for landslide observation. We show that synergizing P/L/C-band SAR can provide the optimal solution for efficient and effective large-scale mapping and kinematic characterization of landslides along the U.S. west coast.