Investigating the effect of intense rainfall events in estimating the displacements of an active and fast-moving landslide using A-InSAR analysis: the case study of Pissouri Village in Cyprus

Pissouri village located in Limassol, Cyprus, has been experiencing an active and fast-moving landslide, resulting to devastating consequences in the village. Since 2017, the impact of the landslide, especially during intense rainfall events in winters, has led to necessitated evacuations, severe damage to properties and the wider landscape. Since 2021, the Laboratory of Geodesy of Cyprus University of Technology has established the CyCLOPS (Cyprus Continuously Operating Natural Hazards Monitoring and Prevention System). One of the case studies that CyCLOPS focuses on is Pissouri, installing three (3) GNSS mobile stations, three (3) GNSS antennas withing the sliding zone, resulting to continuous monitoring of the landslide-affected zone. This study presents an initial attempt to investigate the displacement rates of the landslide, especially during heavy rainfalls seasons, utilizing the CyCLOPS strategic infrastructure unit. Sentinel-1 acquisitions are obtained in ascending mode, covering an interval time from July 2021 to January 2023. Amongst others, rainfall data are complementary used and processed in a GIS environment for visualization purposes. The results of the study indicated that there is a significant relationship between the heavy rainfall seasons and the displacement trends. In cases of an active and fast-moving landslide, the integration of both Synthetic Aperture Radar (SAR) and Global Navigation Satellite System (GNSS) data is essential to monitor, estimate and understand the displacement rates of the landslide and the impact of the intense rainfall events in those cases.