Student Theses Glaciology

Background: Ice avalanches are an important hazard in all glacierized mountain regions. In Switzerland, ice avalanches have repeatedly caused damages, claimed lives, or required special monitoring efforts to protect infrastructure and livelihoods. Some of the most notable events include the ice avalanches from Altels (Kt. Bern) in 1895 and from Allalingletscher (VS) in 1965. Currently, climate change is leading to dramatic shrinkage of glaciers worldwide, with unknown consequences for ice avalanche activity. While ice avalanches will eventually disappear as a hazard, the transient effect of climate change is expected to lead to a rapidly changing behavior of ice avalanche activity that is strongly dependent on the geometric conditions of the glacier during its retreat.

The goal of this study is to combine (i) the knowledge about different types of ice avalanches and their release conditions with (ii) simulations of future glacier extents in order to asses future hotspots of ice avalanche activity until 2100. We can extract (i) from an inventory of ice avalanches maintained by The Laboratory of Hydraulics, Hydrology and Glaciology (VAW-GL). Once the typical release situations/geometries have been identified, this information can be applied to the simulations of future glacier extents (ii) which have been computed with GERM, the Glacier Evolution Runoff Model (Huss et al., 2008). In combination with terrain data (digital elevation models provided by swisstopo) and some intelligently constructed algorithms or machine learning, we can then identify future ice avalanche source areas. Depending on project progression and time, this can be combined with knowledge about future glacial lakes and infrastructure projects to assess future risks from ice avalanches. Candidate profile: This data deals with large geospatial datasets and likely benefits from some pre-existing programming skills and/or an interest in broadening these skillsets.

Dr. Mylène Jacquemart, Laboratory of Hydraulics, Hydrology, Glaciology (VAW) at ETH D-BAUG jacquemart@vaw.baug.ethz.ch

**Background** Glaciers worldwide are retreating due to climate change, leading to diverse consequences such as sea level rise, changes in water availability, increased natural hazards, and disruptions to tourism. In the European Alps, glaciers are a key attraction, drawing millions of visitors annually. One of the touristic attractivities of glaciers is their role in skiing. However, climate change in and especially recent extreme negative mass balance years have significantly impacted summer skiing (e.g., Abegg and Mayer, 2023). This MSc project aims to assess the effects of climate change on glacier-based ski resorts across the Alps. Potential study sites include Hintertux, Les Deux Alpes, Saas Fee, and Tignes, though other locations may also be considered. **Goal** The goal of this MSc thesis is to apply an ice flow and mass balance model (Van Tricht and Huybrechts, 2023) to various Alpine glaciers that host ski resorts. Using existing models, ice thickness datasets, satellite imagery, mass balance observations, ski resort maps, and meteorological records, the research will simulate historical and future glacier evolution under climate change while accounting for the impact of ski resort activities. **Methodology & Workflow** 1. Familiarisation with the mass balance and ice flow model. 2. Data Collection, including: o Satellite data (snowlines) o Ice thickness measurements and reconstructions (what is available, should we collect?) o Meteorological records o Historical observations o Information from ski resorts (closing dates of the resorts, piste locations) 3. Model Adaptation to incorporate artificial snowmaking and snow farming (similar to tarps). 4. Model Execution & Evaluation of glacier mass balance and ice flow dynamics. 5. Future Simulations considering climate change scenarios and ski resort impact. **References** Abegg, B., & Mayer, M. (2023). The exceptional year of 2022: “deathblow” to glacier summer skiing in the Alps? Frontiers in Human Dynamics, 5, 1154245. Van Tricht, L., & Huybrechts, P. (2023). Modeling the historical and future evolution of six ice masses in the Tien Shan, Central Asia, using a 3D ice-flow model. The Cryosphere, 17, 4463–4485. https://doi.org/10.5194/tc-17-4463-2023

The goal of this MSc thesis is to apply an ice flow and mass balance model (Van Tricht and Huybrechts, 2023) to various Alpine glaciers that host ski resorts. Using existing models, ice thickness datasets, satellite imagery, mass balance observations, ski resort maps, and meteorological records, the research will simulate historical and future glacier evolution under climate change while accounting for the impact of ski resort activities.

For further information please contact Dr. Lander Van Tricht (vantricht@vaw.baug.ethz.ch)

Accurate modelling of glacier mass balance requires the representation of wind-driven snow processes. Yet, the physical representation of these processes is computationally too expensive to include in standard mass balance models and, therefore, requires simplification via parameterization schemes.

This thesis will compare existing but not widely used parameterizations for different climatic regions (continental Alpine glaciers, maritime glaciers in New Zealand, and seasonal snow cover). The aim is to consolidate existing parameterizations for applications in standard energy and mass balance models.

For further information please contact Dr. Ruzica Dadic

Antarctic ice streams feed approximately 90% of Antarctica’s ice into the world’s oceans. These ice streams flow to the ocean through a combination of internal deformation and by sliding over and deforming the rock and sediment that underlies them. Processes at the base of the ice are particularly important to understand as they can result in rapid changes in ice flow velocity at time scales of hours to days and years to centuries. Many of these processes emit acoustic signals which can be recorded at the ice surface making passive-source seismology an ideal tool with which to study them. This project will use existing data to examine the transition where the grounded Kamb Ice Stream crosses into the Ross Ice Shelf and contributes to global sea level.

Project aims include identifying, locating, and characterising seismicity from sources at the base of the ice stream and within the ice shelf. These sources include water flow in a large subglacial drainage channel, and crevasse formation due to flexure of the floating ice shelf as it rises and falls with the tide. To achieve the aims you will use existing tools (e.g. obspy) to process and analyse the data. Basic programming skills, or the desire to develop them, are required. The ideal candidate would also have an interest in glaciology and applied geophysics. Should time allow, the results will be compared with other complementary data (e.g. Global Navigation Satellite System positioning) and model output (e.g. subglacial water routing.)

For further information please contact Dr. Huw Horgan (horganh@ethz.ch)