Experimentation

Scientists from the SLF do more than simply observe nature in order to understand how it works. Through experiments, they are able to create precisely defined conditions, thereby enabling them to answer important questions. Sometimes these experiments extend across entire mountainsides.

At the Stillberg site in Davos, for example, our scientists have planted thousands of trees in order to study the development of the treeline. In Valais, they trigger major avalanches which are then monitored by instruments and cameras as they come thundering down into the valley.

Experiments are at the heart of scientific research. Taking the question (hypothesis) as the basis, our researchers vary the conditions under which a phenomenon occurs. For example, if we want to know how the structure of snow adapts with changing temperatures, we heat the snow samples in the laboratory and observe them via computer tomography.

Masses on the move

An exceptional feature of the WSL and the SLF is our instrumented field sites for mass movements, which are the only ones of their kind in the world. This is where our researchers observe avalanches, debris flows and hillslope debris flows in the field on a realistic scale. State-of-the-art sensors developed by the WSL and SLF measure a wide range of variables, such as flow velocity, impact pressure and shear stress.

The data provides a better understanding of the processes involved in individual natural hazards. This data is also entered into various computer models (e.g. RAMMS), which help practitioners and researchers evaluate natural hazards and develop hazard maps and safety concepts.

For the most part, though, the experiments are much less spectacular; in one location, a masters student gathers specific plants on mountaintops in order to study the effect of competition; in another, a doctoral student uses a specially developed shear apparatus to determine the amount of force required to break the weak layer in a covering of snow and the sounds that this produces.