Wenn Baumwunden dazu beitragen, Steinschlagmodelle weiterzuentwickeln
When tree scars contribute to develop rockfall models Rockfall is an often occurring natural hazard in mountainous areas. Because rocks proceed very quickly with different types of motion, and because their run-out path is influenced by several factors, the implementation of rockfall processes in numerical models is complex. This article presents the methods of visual scar identification on trees and of measuring rock deposits, to validate the accuracy of the RAMMS::Rockfall model within the active rockfall area of Meretschibach (Canton of Valais, Switzerland). Scenarios with different rock shapes and modified terrain parameters were applied to test the sensitivity of the model to these parameters. Using scans of natural rocks from the field site, which are representative in shape and volume resulted in more realistic modelled median jump heights compared to rocks of the same size (small or large), but also to standard RAMMS rocks which were quite similar in shape and volume to the scanned rocks. The best simulations resulted when the terrain type was defined as two classes softer than registered in terrain. In this case, the difference between the simulated median jump height and the height of the scars on trees was just 23 cm. These results led to improvements in the model and handbook. This study highlights the importance of precise field data to better specify input parameters for rockfall modelling.