SAR Data for Detecting Landslide Phenomena: The November 26, 2022 Landslide of the Ischia Island (Southern Italy)

Abstract

In this article, several change detection techniques based on satellite SAR data acquired by Cosmo-SkyMed Second Generation missions have been evaluated aiming at detecting the landslide-mudflow phenomenon triggered by the strong flooding event that hit Ischia Island in November 2022. It severely impacted on Casamicciola Terme area causing damages and collapses of many buildings and unfortunately also casualties. Experimental results show how both single-polarimetric (SP) and dual-polarimetric (DP) techniques are able to detect the main landslide occurring along the northern flank of Mt. Epomeo and in some cases also connected phenomena such as mud accumulation. Additional analyses have been performed to quantitatively evaluate the performance of all of them showing, as in this case, DP techniques outperform the SP ones. The outcomes are then discussed taking into account both the features of each technique and the investigated scenario. Detecting and mapping this kind of phenomenon is important for the evaluation of the affected area, especially for complex scenarios such as Ischia island, and can be very useful to support both the stakeholders for first aid and the civil protection for the post-crisis management.

Keywords

• Change detection
• Ischia island
• landslide
• synthetic aperture radar (SAR) images