A summary of CRMD new research on landslides using multi-temporal InSAR techniques based on Sentinel-1 data
Author: Iuliana Armaș
Abstract: The new landslide research direction at CRMD aims to improve and develop new applications of ground-based validation techniques of satellite radar interferometry displacement products, based on Sentinel-1 data. The test area is the high slope instability ridge of the Carpathian and Subcarpathian Prahova Valley due to natural and anthropogenic factors. We use sets of single polarized synthetic aperture radar (SAR) satellite data acquired by historical (i.e., ERS-1/-2 and ENVISAT) and recent (Sentinel-1) satellites, and multi-temporal radar interferometry (InSAR) methodologies to provide maps of line-of-sight displacements. We apply some of the most advanced differential interferometric Synthetic Aperture Radar techniques at the moment, Persistent Scatterer Interferometry (PSI) and Small BASeline Subset (SBAS); both of them are applied for depicting areal or point deformations. Deformation maps and time series are integrated with Geographical Information System (GIS) multilayer analysis results derived from classical methodologies (i.e., geological and geomorphological methods), and field research. InSAR analyzes are calibrated and validated using GNSS techniques and GIS slope modelling based on Lidar and radar obtained DEMs. The short-term results are highly reliable interferometric measurements. On a long term, the results imply the understanding of slope dynamic in the context of major human environmental change. The latter achievement could offer the support to successful risk mitigation methodologies in mountain areas.
Landslides, InSAR, Permanent Scatterers, SBAS, GNSS.