Evaluating a Prototype Europe-Wide Landslide Early Warning System: High-resolution comparative analysis in Catalonia and Alpes Maritimes

Rainfall-induced landslides pose a major threat to communities across Europe. This study analyses the performance of a prototype Landslide Early Warning System developed within the GOBEYOND project (Project: 101121135) that uses datasets (landslide susceptibility and precipitation) available across Europe.

The prototype is driven by gauge-adjusted precipitation composites from EUMETNET OPERA and the ELSUS v2 susceptibility map (Wilde et al., 2018). The system is designed to provide real-time landslide warnings in regions where local models are not available. Rather than replacing existing systems, the prototype aims to fill gaps in continental-scale monitoring.

The system’s performance is evaluated in two distinct contexts. In Catalonia (NE Spain), the framework is applied to a continuous inventory (2024–2025) to systematically benchmark the European prototype against the local system, which utilizes high- resolution susceptibility data and radar-gauge QPE. Conversely, in the Alpes-Maritimes (SE France), the analysis adopts a targeted approach, focusing on the validation of specific recent events using inventory data.

To account for uncertainties in inventory data (affected by location inaccuracies or imprecise reported dates), the study combines EDuMaP with a fuzzy approach. Preliminary results demonstrate that performance is sensitive to the temporal evaluation window. Extending the window from 24 to 72 hours more than doubled the proportion of correctly detected landslide events, suggesting that the prototype successfully identifies the hazardous conditions when accounting for reporting delays.

The European prototype effectively captures widespread triggering conditions, but its current calibration results in excessive over-forecasting. Therefore, it serves as a valuable baseline hazard indicator for regions with limited data, establishing a homogeneous observation standard across the continent.