SAR data and field surveys combination to update rainfall-induced shallow landslides inventory

The Campania region has been recurrently hit by severe landslides in volcanoclastic deposits. The city of Naples, and in particular the Camaldoli and Agnano hills, also suffered several landslide crises in weathered volcanoclastic rocks as a consequence of intense rainfalls or wildfires. This work provides an updated landslide database for the suburbs of Naples. The obtained database consists of about 1322 landslides considering available information dated back to 1816, identified thanks to the historical newspaper's examination; 62 landslides were recorded between 2019 and 2020. Furthermore, the achieved database is the result of the standardization of available information from different sources, organized in a completely different way. The newly identified phenomena have been recognized thanks to a combination of optical satellite imagery with Google Earth, Sentinel-1 radar satellite imagery and field investigation. The implemented methodology is based on change detection analysis of satellite imagery by using polarimetric features. Subsequently, output derived from the segmentation procedure of satellite images have been compared with field trip observations. The main purpose of this procedure is to emphasize areas where land cover changes, potentially related to slope failures, occur in the Phegraean Fields, facilitating the following possible phases of mapping and/or field survey. Eventually, this type of information is expected to help decision-makers with land planning and risk assessment.