Rock glacier dynamics in the Swiss Alps: Evolution and drivers at multiple spatio-temporal scales (RoDynAlpS)
Mountain permafrost is undergoing substantial modifications due to climate change. In the Alps, a drastic increase in rock glacier creep rates has occurred at the regional scale since the 1990s, concurrent with rising temperatures and changing ice-water ratios within the permafrost. These observations raise questions on the fundamental mechanisms controlling rock glacier dynamics and their coupling to climate. To address these knowledge gaps, the project aims to investigate the evolution of rock glacier dynamics at multiple spatio-temporal scales in the Swiss Alps. The project consists of five work packages based on the review and the analysis of readily existing datasets complemented with original observations produced ad-hoc.
The main objectives are the following: 1. Quantifying and assessing the current state of rock glaciers in Switzerland (Thibaut Duvanel, UniL) 2. Reconstructing and analysing the past evolution of rock glaciers in Switzerland (Mohd. Ataullah Raza Khan, UZH) 3. Identifying and quantifying the physical processes controlling the decadal, inter-annual, and seasonal evolution of rock glaciers (Matthias Lichtenegger, SLF) 4. Investigating the dynamics and destabilization of rock glaciers using numerical models (Yan Hu, UniFr) 5. Identifying rock glacier dynamics at multiple spatio-temporal scales (whole team)
The achievements in this project will constitute an important step forward in rock glacier research in the Alps and beyond, with wide implications for fundamental research and operational monitoring. It will provide the first comprehensive assessment of rock glacier distribution and kinematics at the regional scale worldwide, setting the Swiss Alps as a benchmark in the study of rock glaciers. It will also provide the first regional investigation of multi-temporal velocity variations, constituting the necessary basis for understanding the complex processes governing rock glacier dynamics and their relation to climate change.
Exploring potential drilling sites in the Matter Valley – A RoDynAlpS field trip
A group of 13 from the University of Fribourg (UniFR), University of Zurich (UZH), University of Lausanne (UNIL), the WSL Institute for Snow and Avalanche Research SLF, and international guests came together for a field trip to the Matter valley region, in the ski resort of Grächen. The group brought together a diverse mix of project PIs, partners, PhD students, postdocs, a guest researcher from Bhutan, and an intern from the University of Salzburg. The main goal of the visit was to evaluate two rock glaciers, Ritigraben and Distelhorn, as potential future drilling site and to carefully discuss the possible location of boreholes. Guided by Marcia Phillips (SLF) and Reynald Delaloye (UniFR), the group explored the area around the Grächen ski resort and got a closer look at the Ritigraben and Distelhorn rock glaciers. On site, discussions focused on the pros and cons of both locations, considering logistical challenges, scientific value, and environmental impact. Beyond the technical agenda, the trip offered something just as valuable: time for open exchange, fresh ideas, and spontaneous conversations among colleagues. It was a great opportunity to reconnect in person, enjoy the landscape, and be inspired by the Alpine terrain, reminding us why we study these fascinating environments in the first place.
Special thanks to Reto Imesch and the entire team at Grächen Bergbahnen for their warm welcome and excellent support in organizing logistics within the resort, from and to the potential drilling sites.
(Photo: M. A. Khan, UZH)
Rogithon I – A week of rock glacier mapping across Switzerland
From February 5th to 9th 2024, eight members of the RoDynAlpS project met in Ovronnaz (VS) for a dedicated working week on Work Package 1. This package focuses on assessing and quantifying the current state of rock glaciers in Switzerland. The objective was to identify and locate as many rock glaciers in Switzerland as possible.
Methodology
The team applied the first step of the International Permafrost Association’s (IPA) Rock Glacier Inventory and Kinematics (RGIK) guidelines, which involved placing a point (a “Primary Marker”) within a GIS project on each detected rock glacier unit.
The investigations primarily relied on a dataset provided by Swisstopo, which included current and historical aerial orthoimages, topographic maps, as well as the latest digital elevation model, known as the Swiss Surface 3D Raster and derived from airborne LiDAR data (spatial resolution of 0.5 m). Additionally, the operators used SAR interferograms produced by Gamma Remote Sensing from Sentinel 1 images acquired between 2020 and 2022. The investigations mainly focused on areas above 1000 m a.s.l., excluding the Berne canton due to unavailability of the Swiss Surface 3D Raster DEM at that time. The study area was divided into 500 sub-areas, each assigned to a team operator.
Results
At the end of the Rogithon week, around 9000 rock glacier units had been provisionally identified, including around 2000 uncertain rock glacier units that require further investigation (e.g. field visits) to either confirm or dismiss as many as possible. Plus, in order to minimize subjectivity as much as possible, a double-check will be carried out by a restricted number of operators.
Project Kick-Off Villars-sur-Glâne
Six months after the beginning of the RoDynAlpS project, the RoDynAlpS team met with the project partners in Villars-sur-Glâne, in the Café des Préalpes. The aim of the day was to share an overview of the project with the external partners and to discuss the progress made in the individual work packages. For the PhD students, it was an opportunity to engage in discussions with them, and to ask more technical questions about some of the datasets provided by them (such as aerial ortho-photographs from swisstopo, or SAR interferograms from Gamma Remote Sensing).
In the morning, after a presentation by Reynald Delaloye on the context of the project and its history, each PhD student presented the work package in which they are involved. Cecile Pellet then briefly presented work package 4, which will be mainly led by Yan Hu, during her three-year post-doctoral fellowship in Fribourg.
After lunch, Tazzio Strozzi (Gama Remote Sensing) presented the interferogram dataset his company provided to the project team, and Francesco Brardinoni (University of Bolzano) gave a talk about recent research led by his team, on a rock glacier inventory in the Italian Alps. We ended the day with interesting discussions over an apéritif.
