Systematic application of photomonitoring for landslide surveillance in Italy: first results from the geosciences IR project

Abstract

This study presents results from the first systematic evaluation of Photomonitoring techniques for landslide surveillance at national scale, conducted within the PNRR “Geosciences IR” project. Between January 2024 and June 2025, thirteen landslide sites across Italy were monitored using 15 cameras, including a UAV system. Change detection analysis identified 1235 gravitational events spanning five orders of magnitude (0.007–2080 m2). Quantitative validation at Baldiola earthflow against robotic total station measurements yielded correlation coefficients of r = 0.831–0.999 (mean 0.966), demonstrating accuracy comparable to conventional geodetic techniques. Meteorological correlation analysis at Baldiola confirmed rainfall-triggered mechanisms (r > 0.973) consistent with previous studies, while seasonal acceleration patterns at La Saxe aligned with documented snowmelt-driven processes. Fixed camera installations demonstrated superiority over periodic monitoring approaches that suffer of changes in lighting conditions and large variations in the scene (e.g. snow or vegetation coverages). This study establishes Photomonitoring as a cost-effective technique for operational landslide surveillance.