Ground-penetrating radar is a widely utilised method in a number of disciplines, including engineering, archaeology and glaciology. One challenge in analysing radar data is the lack of knowledge about the wave speed. In this study, we employ SBI to determine the wave velocity for a simple structured subsurface.

In my PhD project, I will work on improving the radar simulator from my master thesis to simulate radar data for different thermal regimes, basal conditions (ice frozen to bed vs. thawed ice), and internal structures of the ice. Subsequently, I will use this data within a simulation-based inference framework to disentangle how the different conditions inscribe themselves in radar measurements and to derive temperature profiles and basal reflectivity from radar measurements. This would allow for a better characterization of the basal and thermal state of Antarctica’s ice sheet. My PhD project is funded by a scholarship of the Heinrich-Böll-Stiftung.

Ice shelves, which are extensions of ice sheets connected to land but floating on the ocean, encompass over 75% of the Antarctic perimeter and act as an ice wall that restrains grounded glaciers. Within ice shelves, shear zones typically occur from grounding zones where fast outlet glaciers encounter slower floating ice for the first time. Here we investigate mechanisms that determine the evolution and strength of shear zones. This includes the seeding of the shear-zones at glacier outlets near the grounding zone, the evolution of the shear-zone in the mid-shelf region, and the role of shear zones in crevasse formation and iceberg calving at the ice-shelf front. Understanding these processes is crucial for refining computer models that predict Antarctica's contribution to global sea-level rise.

Within the Priority Programme SPP1158 from the German Reserach Foundation, the project QUASNO will investigate changes in snow accumulation and surface mass balance on the plateau of the DML during the last 500 years. It combines new airborne radar measurements, firn core data and statistical techniques to reconstruct spatio-temporal accumulation fields. The outcome will reduce the uncertainty on the role of climate change to global mean sea level rise in the 21st century.

In this project, we are developing a new phase-coherent radar system to measure basal melt rates along km-long profiles. Understanding basal melt rates over wide areas is essential for better predictions of the stability of ice shelves and thus sea level rise. Current radar systems do not allow measurements of basal melt along profiles. Therefore, we will develop a new radar system as part of a PhD Project in cooperation with the institute for microwave technology in Ulm. 

Predictions of melting glaciers and polar ice sheets require a better understanding of the processes driving their deformation. Here we dive into glacier dynamics by studying Grenzgletscher, Switzerland, using advanced radar technology.

Ice crystals are mechanically and dielectrically anisotropic, meaning that their deformation behaviour and capability to transmit electromagnetic waves have a directional dependence. These anisotropic properties transfer to the bulk behaviour of polycrystalline ice in glaciers, ice sheets and ice shelfs. Accordingly, the macroscale flow dynamics of these ice masses depend on the microscale distribution of the orientations of ice crystals (also called 'ice fabric') within them. Thanks to the dielectric anisotropy, ice fabric can be measured with polarimetric radar techniques. In particular, using phase-sensitive radar small differences in the directionally dependent propagation velocities can be observed, allowing to reconstruct the ice fabric. Similarly, the detection of the englacial stratigraphic structure can be improved by applying interferometric techniques to profiles acquired with phase-sensitive radar. This englacial structure again allows to decipher past ice deformation, which is potentially controlled by the ice fabric.

This project is funded by a doctoral scholarship of the German Academic Scholarship Foundation (Studienstiftung des deutschen Volkes).

My PhD research focuses on modelling groundwater recharge for snow-covered soils along hill slopes. Specifically, I investigate water flow dynamics in snow and the underlying soil layers on the Darcy scale. The goal of my project is to quantify lateral runoff driven by processes such as the formation of ice slabs and the development of capillary barriers. Quantifying groundwater recharge and lateral runoff in alpine regions is crucial for effective water management and to improve our understanding of flooding events triggered by snowmelt.