TY - JOUR A1 - Goetz, Jason A1 - Kohrs, Robin A1 - Parra Hormazábal, Eric A1 - Bustos Morales, Manuel A1 - Araneda Riquelme, María Belén A1 - Henríquez Ruiz, Cristian A1 - Brenning, Alexander T1 - Optimizing and validating the Gravitational Process Path model for regional debris-flow runout modelling JF - Natural hazards and earth system sciences : NHESS / European Geophysical Society N2 - Knowing the source and runout of debris flows can help in planning strategies aimed at mitigating these hazards. Our research in this paper focuses on developing a novel approach for optimizing runout models for regional susceptibility modelling, with a case study in the upper Maipo River basin in the Andes of Santiago, Chile. We propose a two-stage optimization approach for automatically selecting parameters for estimating runout path and distance. This approach optimizes the random-walk and Perla et al.'s (PCM) two-parameter friction model components of the open-source Gravitational Process Path (GPP) modelling framework. To validate model performance, we assess the spatial transferability of the optimized runout model using spatial crossvalidation, including exploring the model's sensitivity to sample size. We also present diagnostic tools for visualizing uncertainties in parameter selection and model performance. Although there was considerable variation in optimal parameters for individual events, we found our runout modelling approach performed well at regional prediction of potential runout areas. We also found that although a relatively small sample size was sufficient to achieve generally good runout modelling performance, larger samples sizes (i.e. >= 80) had higher model performance and lower uncertainties for estimating runout distances at unknown locations. We anticipate that this automated approach using the open-source R software and the System for Automated Geoscientific Analyses geographic information system (SAGA-GIS) will make process-based debris-flow models more readily accessible and thus enable researchers and spatial planners to improve regional-scale hazard assessments. Y1 - 2021 U6 - https://doi.org/10.5194/nhess-21-2543-2021 SN - 1561-8633 SN - 1684-9981 VL - 21 IS - 8 SP - 2543 EP - 2562 PB - European Geophysical Society CY - Katlenburg-Lindau ER - TY - JOUR A1 - Oncken, Onno A1 - Luschen, Ewald A1 - Mechie, James A1 - Sobolev, Stephan Vladimir A1 - Schulze, Albrecht A1 - Gaedicke, Christoph A1 - Grunewald, Steffen A1 - Bribach, Jens A1 - Asch, Günter A1 - Giese, Peter A1 - Wigger, Peter A1 - Schmitz, Michael A1 - Lueth, Stefan A1 - Scheuber, Ekkehard A1 - Haberland, Christian A1 - Rietbrock, Andreas A1 - Götze, Hans-Jürgen A1 - Brasse, Heinrich A1 - Patzwahl, Regina A1 - Chong, Guillermo A1 - Wilke, Hans-Gerhard A1 - Gonzalez, Gabriel A1 - Jensen, Arturo A1 - Araneda, Manuel A1 - Vieytes, Hugo A1 - Behn, Gerardo A1 - Martinez, Eloy T1 - Seismic reflection image revealing offset of Andean subduction-zone earthquake locations into oceanic mantle Y1 - 1999 ER -