A Convolutional Neural Network-based approach for automatically detecting rainfall-induced shallow landslides in a data-sparse context

Detecting rainfall-induced shallow landslides in data-sparse regions has become increasingly important for effective landslide disaster management. Previous studies have predominantly focused on automated methods for deep-seated, earthquake-triggered landslides. This study addresses this gap by employing a U-net Convolutional Neural Network (CNN) model to detect rainfall-induced shallow landslides using multi-temporal, high-resolution PlanetScope (3m spatial resolution), medium-resolution Sentinel-2 (10m spatial resolution) imagery, and ALOS-PALSAR-provided digital elevation model (DEM). Four datasets were created: Datasets A and B using PlanetScope, and Datasets C and D using Sentinel-2, with Datasets B and D also including DEM data. A total of 181 manually delineated landslide polygons were used as ground truth masks. Each dataset was tested using repeated stratified hold-out validation. Performance metrics included precision, recall, F1 score, loss, and accuracy. Results indicated that Datasets A and B outperformed the others; however, integrating DEM with Dataset B did not enhance model accuracy. The best mean precision, recall, F1 score, loss, and accuracy were 1, 0.625, 0.625, 0.380, and 0.999, respectively, for both Datasets A and B. This study demonstrates the U-net model's potential for detecting rainfall-induced shallow landslides in various geographic and temporal contexts globally.