Unified landslide hazard assessment using hurdle models

Published: 25 October 2022

This model represents the first attempt to simultaneously address two out of the three requirements of the landslide hazard definition, namely, the probability of observing a landslide and its size.

The most accepted definition of landslide hazard requires the definition of the probability, the time or frequency of occurrence, and an indication of the level of threat a landslide may pose. The latter can be estimated in various forms, these being the velocity, kinetic energy or the impact force of a moving mass, by solving mechanical equations that require detailed knowledge about soil hydrology, friction parameters and more. However, over large areas, densely collecting these measurements is impossible due to the costs of laboratory tests and the inaccessibility of the highest portions of a landscape. For this reason, for fifty years geomorphologists have focused most of their scientific efforts on assessing where landslides are likely to manifest across a given landscape, leaving unexplored the component that pertains to the level of threat. In this work, we propose a new paradigm where the landslide area is modelled together with the probability of landslide occurrence. This model represents the first attempt to simultaneously address two out of the three requirements of the landslide hazard definition. This is an unprecedented achievement, and it also represents an uncharted territory as it offers an alternative to standard protocols used by decision-makers to minimise the risk of landslides to which mountain communities are exposed. The article is available here.

 

Reference

Bryce, E.Lombardo, L., van Westen, C., Tanyas, H., & Castro-Camilo, D. (2022). Unified landslide hazard assessment using hurdle models: a case study in the Island of Dominica. Stochastic Environmental Research and Risk Assessment, 1-14.


First published: 25 October 2022