The Role of Collecting Data on Various Site Conditions Through Satellite Remote Sensing Technology and Field Surveys in Predicting the Landslide Travel Distance: A Case Study of the 2022 Petrópolis Disaster in Brazil

Landslide runout distance is governed not only by collapsed magnitude but also by site-specific geoenvironmental conditions. While remote sensing techniques has advanced landslide susceptibility mapping, its application to runout modeling remains limited. This study examined the role of collecting data on various site conditions through remote sensing and field surveys datasets in predicting the landslide travel distance from the 2022 disaster in Petrópolis, Rio de Janeiro. A total of 218 multivariate linear regression models were developed using morphometric, remote sensing, and field survey variables collected across collapse, transport, and deposition zones. Results show that predictive accuracy was limited when based solely on landslide scale (R2 = 0.06–0.10) but improved substantially with the inclusion of site condition data across collapse, transport, and deposition zones (R2 = 0.49–0.51). Additionally, model performance was strongly influenced by runout path typology, with channelized flows producing the most stable and accurate predictions (R2 = 0.73–0.90), while obstructed and open-slope paths performed worse (R2 = 0.39–0.61). These findings demonstrate that empirical models integrating multizonal site-condition data and runout path typology offer a scalable, reproducible framework for landslide hazard mapping in data-scarce, complex mountainous urban environments.