Assessing the quality of landslide susceptibility maps – case study Lower Austria

Author(s)
Helene Petschko, Alexander Brenning, Rainer Bell, Jason Nicholas Goetz, Thomas Glade
Abstract

Landslide susceptibility maps are helpful tools to identify areas potentially prone to future landslide occurrence. As more and more national and provincial authorities demand for these maps to be computed and implemented in spatial planning strategies, several aspects of the quality of the landslide susceptibility model and the resulting classified map are of high interest. In this study of landslides in Lower Austria, we focus on the model form uncertainty to assess the quality of a flexible statistical modelling technique, the generalized additive model (GAM). The study area (15 850 km2) is divided into 16 modelling domains based on lithology classes. A model representing the entire study area is constructed by combining these models. The performances of the models are assessed using repeated-fold cross-validation with spatial and random subsampling. This reflects the variability of performance estimates arising from sampling variation. Measures of spatial transferability and thematic consistency are applied to empirically assess model quality. We also analyse and visualize the implications of spatially varying prediction uncertainties regarding the susceptibility map classes by taking into account the confidence intervals of model predictions. The 95% confidence limits fall within the same susceptibility class in 85% of the study area. Overall, this study contributes to advancing open communication and assessment of model quality related to statistical landslide susceptibility models.

Organisation(s)
Department of Geography and Regional Research
External organisation(s)
University of Waterloo (UW)
Journal
Natural Hazards and Earth System Sciences
Volume
14
Pages
95-118
No. of pages
24
ISSN
1561-8633
DOI
https://doi.org/10.5194/nhess-14-95-2014
Publication date
01-2014
Peer reviewed
Yes
Austrian Fields of Science 2012
107007 Risk research
Portal url
https://ucrisportal.univie.ac.at/en/publications/c392fba0-0933-403d-9507-d4c947059680