An effective method to detect and measure earthflow displacements using a hybrid interferometric approach

This study presents a new application of the Sentinel-1 dataset for the detection and measurement of earthflow displacements. The proposed methodology utilizes a multi-baseline interferometric hybrid approach, leveraging the backscattered radiation from both point-like and distributed radar targets. The analysis takes into consideration eight datasets acquired between 2017 and 2020, both on ascending and descending orbits, but it is restricted to seven months of the yearly acquisitions, spanning from late March to the beginning of November, to mitigate temporal decorrelation and minimize the impact of snow cover. The investigated area is part of the Dolomites Unesco World heritage site (Eastern Italian Alps). The results so far obtained are then compared with those derived from the European Ground Motion Service (EGMS) and in-situ Global Navigation Satellite System (GNSS) monitoring networks. Preliminary findings reveal the promising reliability of this approach, demonstrating its efficacy and accuracy. Furthermore, this methodology offers a notable advantage in terms of spatial sampling, resulting in the enhancement of the capability to identify and characterize earthflows movement. Overall, this study underscores the potential of utilizing Sentinel-1 data for monitoring landslides distinguished by significantly high rates of displacement, by loosening some of the well-known constraints of the interferometric analyses. The findings highlight the importance of space-borne SAR missions in providing valuable insights in landslide risk mitigation and management.