Dynamics of snow melt infiltration into mountain soils: an instrumental approach in the Nant Valley, Swiss Alps

Abstract. To gain a deeper understanding of the dynamics of the contribution of snow melt to mountainous water cycles, it is necessary to better grasp the parameters controlling the infiltration of snow melt into mountainous soils. This research uniquely combines snow melt rate data with soil moisture dynamics, providing a comprehensive, three-year dataset. The integration of multiple measurement techniques and the estimation of the snow melt rate through the measurement of snow resistivity offer a new perspective on snow melt infiltration processes. The study area is located in the Nant Valley, Swiss Alps. Measurement points are distributed in mid to high elevations in various alpine environments. Besides demonstrating the instrumental setup, we also investigated the snowmelt-infiltration dynamics in the study area. Results indicate that, even though melt rates are considerably lower than soil saturated hydraulic conductivity values (with a ratio of 3.1x10^-3 on average), the response times of shallow soil moisture and stream discharge to melt events is fast (from 2 to 5 hours). At the point measurement, snowmelt hardly infiltrates below 30 cm. These findings emphasize the potential vulnerability of mountain areas to dry periods in the future, particularly in the context of the expected shortening of the melt period due to climate change.