Persistent Scatterer Interferometry and Statistical Analysis of Time-Series for Landslide Monitoring: Application to Santo Stefano d’Aveto (Liguria, NW Italy)

Abstract

Landslides are a major threat for population and urban areas. Persistent Scatterer Interferometry (PSI) is a powerful tool for identifying landslides and monitoring their evolution over long periods and has proven to be very useful especially in urban areas, where a sufficient number of PS can be generated. In this study, we applied PS interferometry to investigate the landslide affecting Santo Stefano d’Aveto (Liguria, NW Italy) by integrating classic interferometric techniques with cross-correlation analysis of PS time-series and with geological and geotechnical field information. We used open-source software and packages to process Synthetic Aperture Radar (SAR) images from the Copernicus Sentinel-1A satellite for both ascending and descending orbits over the period 2015–2021 and calculate both the vertical motion and the E-W horizontal displacement. By computing the cross-correlation of the PS time-series, we identified three families of PS with a similarity greater than 0.70. The cross-correlation analysis allowed subdividing the landslide in different sectors, each of which is characterized by a specific type of movement. The geological meaning of this subdivision is still a matter of discussion but it is presumably driven by the geomorphological setting of the area and by the regional tectonics.

On the Processing of Dual-Channel Receiving Signals of the LuTan-1 SAR System

“…(1) The descending coseismic interferograms of the Wenchuan earthquake (Sichuan, China) given in [35] using the datasets of the ALOS-2 data (larger map) and Envisat data (smaller map), and (2) the evolution of the 2018 Jinsha River landslide (Tibet, China) given in [2] using the SAR data from the GAOFEN-3 (GF-3) satellite. Other practical deformation measurement examples can be found in [3,[36][37][38][39]. After the LT-1 enters the service, its data will support the deformation measurement applications described above.…”

“…2 The symbol "R" represents that the reconstruction method is better under the corresponding item, the symbol "S" represents that the synthesis method is better, and the symbol "≈" represents that there is no significant difference between the two methods. 3 Refers to where the channel phase error is 5 • and the along-track baseline error is 10 cm. 4 The evaluation values of the NESZ under the two methods are obtained at the same incident angle.…”

“…Synthetic aperture radar (SAR) can provide remote sensing abilities during the day and night regardless of weather conditions, so it plays an important role in Earth and planetary observation [1,2]. The ability of SAR satellites to measure the displacement of landmasses cross the country, even on the global scale, can effectively deal with disasters including landslides and earthquakes [2,3]. Furthermore, to pursue better penetration capacity, the L-band has been adopted in more and more spaceborne SAR missions, such as ALOS-2 launched in 2014 [4], SAOCOM-CS [5][6][7], TanDEM-L [8][9][10][11], and LuTan-1 (LT-1) introduced in this paper.…”

Analysis of Deformation Dynamics in Guatemala City Metropolitan Area Using Persistent Scatterer Interferometry

“…In our case, default parameter values led to an irregular stepped trend in several PS time series. To address this, parameters related to atmospheric filtering, phase unwrapping, and estimation of the Spatially Correlated Look Angle (SCLA) error have been set to values explained by Balbi et al 2021 [62]. Specifically, these modified parameters introduced in the final steps of StaMPS that allowed us to obtain a more natural trend are as follows: "unwrap_time_win" set to 24 days (default 730 days) to smooth the phase in time by estimating noise for each pair of neighboring pixels; "unwrap_grid_size" set to 10 m (default 200 m) for spacing of the resampling grid; "unwrap_gold_n_win" set to 8 (default 32) for the size of the window used in the Goldstein filter; "scla_deramp" set to "yes" (default "no") to estimate the phase ramp for each interferogram; and "scn_time_win" set to 50 days (default 365) for the window size of the low-pass temporal filter.…”

Surface deformation analysis in Northeast Italy by using PS-InSAR and GNSS data 

“…Among other phenomena that induce surface displacements and may be detected by geodetic data, we must mention landslides and slope instabilities. Indeed, the potential of geodetic data has been successfully exploited for detecting and estimating these phenomena (e.g., Colesanti and Wasowki, 2006;Notti et al, 2015;Balbi et al, 2021). However, these methods also present some limitations that should be considered in these investigations.…”