Modeling gravitational mass movements in the Swiss Alps

© Johan Gaume / EPFL 2020

© Johan Gaume / EPFL 2020

Johan Gaume, the director of EPFL’s Snow and Avalanche Simulation Laboratory (SLAB), has been awarded a Swiss National Science Foundation grant to model gravitational mass movements in the Alps – a potentially devastating phenomenon that will grow in frequency as climate change takes hold.

On 23 August 2017, a vast section of rock broke away from Piz Cengalo, a mountain in Grisons Canton, eastern Switzerland. The landslide impacted a glacier below, mixing with meltwater to form a fast-moving debris flow that cascaded down the slope toward the village of Bondo. Although residents were evacuated in time, the unfortunate chain of events claimed the lives of eight people on the mountain and caused CHF 41 million in damage.

Events like these are still a rare occurrence. But scientists predict they will become more commonplace as the effects of climate change – melting glaciers and thawing permafrost – undermine the stability of mountain slopes. Johan Gaume, who heads the Snow and Avalanche Simulation Laboratory (SLAB) at EPFL, is planning to develop a new way to model these phenomena, known as gravitational mass movements. His research could pave the way for better mitigation and anticipation.

“Gravitational mass movements are a major concern in Switzerland, and across the Alps in general,” says Gaume. “They’re happening more often as global temperatures rise, and especially as permafrost thaws. We saw a huge number of rock avalanches this summer. Some of them, like the one that struck at Piz Cengalo, can trigger complex process chains and cause serious damage. With so many Swiss villages at risk, we need to get better at predicting and managing these events.”

The project has received a CHF 96,000 grant from the Swiss National Science Foundation’s (SNSF) Spark program, which supports the development of new scientific ideas and methods that “show unconventional thinking and introduce a unique approach”.

Predicting where landslides will strike

The SLAB team, which specializes in avalanche simulation, will hire a postdoctoral researcher to develop a novel mechanical model to study rock and permafrost. “The advantage of our approach is that we can simulate how a landslide is triggered, how it flows, and how it impacts man-made structures,” explains Gaume. “We were keen to see whether we could apply our model to materials other than snow, and to simulate the process by which landslides turn into torrential debris flows.”

The researchers will have 12 months to demonstrate the model’s potential. Working with the Institute for Snow and Avalanche Research (WSL) in Davos, the team will draw on existing data to attempt to recreate the Piz Cengalo event. Gaume will also test out his model on less complex formations, subjecting them to air temperature variations and observing the effect on rock-mass cohesion and stability. 

“Our methods could help predict instabilities and mitigate the threat to Alpine villages,” adds Gaume.

Looking further ahead, the new model developed at SLAB could be used in local hazard mapping, identify where protective structures are required, or even inform evacuation planning.


The aim of SNF's Spark is to fund the rapid testing or development of new scientific approaches, methods, theories, standards, ideas for application, etc. It is designed for projects that show unconventional thinking and introduce a unique approach. The focus is on promising ideas of high originality, with minimal reliance on preliminary data. Taking risks is very welcome, but not a requirement in itself. The focus is on projects or ideas that are unlikely to be funded under other funding schemes.

The proposals are evaluated in a double-blind reviewing process (i.e. the identity of the applicant will not be disclosed to the evaluators). In this way, the SNSF aims to ensure that the evaluation will focus on the project idea.