Glaciology and Geophysics - Who is Who

Meet the group!

Guest Researchers

Benedict Ejelonu (fellow of the Data Science & AI Fellowship Program together with the African Institute for Mathematical Sciences) is working on retrieving subsurface velocities from common midpoint radar data using simulation-based inference.

Staff

Jullien, Nicolas

+49-(0)7071-29-73150

Raum 3R35, Geo- u. Umweltzentrum

I am a glaciologist with a background in environmental engineering who uses radar data to understand physical processes in the shallow layers of the polar ice sheets. I relate distinctive features in the firn layer to multi-year atmospheric conditions and evaluate their influence on the local surface mass balance. I joined the Geophysics Group in April 2026, where I am currently dedicated to understanding spatial snow accumulation patterns near the German research station Neumayer. This project echoes previous work I conducted during my master's thesis, in which I studied the low-level atmospheric sublimation of precipitation over Adélie Land in coastal Antarctica. I completed my PhD at the University of Fribourg, where I investigated the development of ice slabs several metres thick within the firn layer of the Greenland Ice Sheet percolation zone and their implications for surface meltwater runoff. Outside working hours, I enjoy cycling in the beautiful nearby Swabian Jura.

Noll, Johannes

+49-(0)7071-29-73444

Raum 3R31, Geo- u. Umweltzentrum

I have a background in physics with a Bachelor’s and Master’s degree obtained from the University of Heidelberg. After focusing on quantum mechanics in my early studies, I moved to the field of environmental physics, where I worked on inverse modeling of groundwater age distributions in my Master’s thesis.

Since 2024 I am a PhD student in the Geophysics group. In my PhD project I aim to construct a new ground-based radar system for investigating basal melt rates of ice shelves in Antarctica. To achieve a high spatial and temporal resolution, the system is designed to be phase-sensitive and mobile. I will collaborate with researchers from the Institut für Mikrowellentechnik in Ulm, to incorporate their radar expertise into the development process.

Hermann, Anne

+49-(0)7071-29-75034

Raum 6U12, Geo- u. Umweltzentrum

After finishing my Bachelor’s degree in Mathematics in Erlangen, I joined the Geophysics group in 2023 to work on my Master’s thesis as part of the Applied and Environmental Geoscience Master’s program, which I completed in summer 2024. I am now a PhD student supervised by Prof. Olaf Cirpka from the Hydrogeology group and Prof. Reinhard Drews from the Geophysics group.

My PhD project focuses on modelling groundwater recharge in snow-covered soils. Specifically, I am interested in modelling water flow dynamics in snow and underlying soil layers at the Darcy scale. I aim to quantify the lateral runoff driven by processes such as the formation of ice slabs and the development of capillary barriers.

Muhle, Leah Sophie

+49-(0)7071-29-73444

Raum 3R31, Geo- u. Umweltzentrum

I initially joined the geophysics group for my master thesis in Physics in 2022. Since then I completed my MSc and in April 2024 started as a PhD student. My PhD research works on improving the inference of englacial temperature and basal reflectivity from radar measurements. To do so, I will create a radar forward simulator to generate synthetic radar data for different thermal regimes, basal conditions (e.g. frozen or thawed bed) and internal ice structures. The synthetic data will subsequently be used 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 could ultimately allow for a better characterisation of the basal and thermal state of Antarctica’s ice sheet and could improve projections of the ice sheet’s future evolution. First steps for this project were done in my master thesis. There, I began to develop the radar forward simulator by coupling stratigraphy and temperature fields derived from ice flow modelling to the radar forward model gprMax, which yields realistic radargrams of ice sheets. For my PhD project I will also collaborate with the Machine Learning in Science group at the University of Tübingen. The project is funded by a scholarship of the Heinrich Böll Stiftung.

Zuhr, Alexandra

+49-(0)7071-29-73150

Raum 3R35, Geo- u. Umweltzentrum

I am a postdoctoral researcher in the Geophysics Research group and have a background is in climate and environmental sciences. My research focuses on polar regions and ice-covered areas. My PhD focused on the climatic information stored in proxy data in palaeoclimate archives, such as ice cores and marine sediments. I used a variety of statistical tools to improve the understanding of the proxy signal in, for example, stable water isotopes in snow and ice. Out of this, my research interest for snow accumulation and surface mass balance developed. For my current postdoctoral position within the Geophysics Research group, I am focusing on the changes in snow accumulation and surface mass balance on the plateau area in Dronning Maud Land, East Antarctica. The internal layers of snow and firn, mapped in radar data, can be interpreted as the amount of snowfall during a defined period of time. We use this information to infer changes in snow accumulation and surface mass balance related to past changes of temperature in East Antarctica.
My project is financed by the German Research Foundation and part of the Priority Programme 1158 - Antarctic Research. Besides my research, outreach, education and networking is important for me and I am involved in the Association of Polar Early Career Scientists (APECS), especially of the German national committee.

I am also happy to supervise Bachelor and Master thesis as well as student assistants. We are open to ideas and project proposals from students and also have potential projects. Feel free to contact me or come by my office.

Schlegel, Rebecca

+49-(0)7071-29-73150

Raum 3R35, Geo- u. Umweltzentrum

I am a glaciologist and geophysicist working in the geophysics group at the University of Tübingen since summer 2023. My current research focuses on bed properties and topography beneath ice streams and glaciers and their interplay with ice dynamics. I use different geophysical techniques, but mostly focussing on radar and seismics to map subglacial topography with a high resolution. Using these data, I am trying to understand the processes and conditions under which subglacial topography evolves and how we can use this information to better feed numerical models of ice dynamics. During my PhD at Swansea University (2022) I mainly focussed on subglacial bedforms such as drumlins and mega-scale glacial lineations beneath Rutford Ice Stream in West Antarctica. Bedforms are found under fast-flowing ice streams, and are known to affect and record ice flow, providing insights into the interaction of ice dynamics and the subglacial environment.
Following my PhD, I have extended my area of research to Thwaites Glacier in Antarctica and Glaciers in Iceland. Because there is always a gap between theory and observations, especially when it comes to subglacial bedforms, I have worked with numerical models (Elmer ice) as part my post-doc at the British Antarctic Survey in Cambridge and at Swansea University to see if conditions and processes identified using the geophysical data can initiate bedforms. I would like to continue working on these models in the future incorporating more observations.

I am currently working on data from Antarctica and Iceland, and I would be very happy to provide and supervise student projects using these data. If this is of interest for you and you would like to hear more about it, please drop by my office or send me an email.

Drews, Reinhard

+(49) 7071-29-73157

Raum 3U37, Geo- und Umweltzentrum

I am currently leading the Geophysics group at Tübingen University. My main scientific focus is in Glaciology, in particular the Earth’s two remaining ice sheets Antarctica and Greenland. I have done much field work in alpine and polar settings mostly using airborne/ground-based radars & GNSS. I am most interested in the ice-sheets’ perimeter where they come in contact with the ocean. At this interface, basal melting occurs and (at least some) people say that this point defines the stability of the entire ice sheet. For understanding past and future sea level variations this is the go-to area at the moment. Other geophysical tools that I use include ground-based radar interferometry, Lidar, and seismics. In many of my studies, I link the geophysical observations to numerical models . I am increasingly interested to dive into more terrestrial geophysics, e.g., critical zone research and geohazards that link well with the Department of Geosciences.

Publications:

https://orcid.org/0000-0002-2328-294X

https://scholar.google.de/citations?user=aCUjFwUAAAAJ&hl=de

Former Members

Moss, Guy

Moss, Guy

This project is hosted by the machine learning cluster of excellence with Prof. Jakob Macke (https://www.mackelab.org) at the University of Tübingen.

I am a PhD student working with the lab, interested primarily in inferring the history of ice sheets using radar isochrones. I obtained my Master’s degree in Mathematics and Physics at the University of Warwick, which established my interest in interdisciplinary work. Numerical simulations of ice sheets are sensitive to a large set of parameters, such as basal melting and accumulation rates. These simulations are computationally intensive, and so researchers face difficulties in inferring these parameters, which are vital to understanding the history of ice sheets. I will be working with the Machine Learning for Science group in the University of Tübingen to develop and apply Simulation Based Inference, a new family of algorithms for performing Bayesian Inference, to ice sheet simulations. These algorithms seek to improve on traditional methods by:

1. Providing probability distributions over parameter values, as opposed to point estimates.

2. Considerably improving sample efficiency, thus reducing the number of simulations required and speeding up the learning process.

Wild, Christian

Wild, Christian

I'm a geophysicist specializing in Antarctic ice shelves and their interaction with the global ocean circulation. My research focuses on understanding the impacts of atmospheric and oceanic warming on ice shelf stability, with a special emphasis on Thwaites Glacier and its counterparts – each with its own story to tell!

I've embarked on seven research expeditions to Antarctica, spending nearly a year of my life camping out under the stars (or, you know, the mesmerizing blue polar nightsky). I thrive on taking a comprehensive approach to research, blending satellite remote sensing with computer simulations, often requiring hands-on fieldwork and sometimes even poking things with a stick. Throughout this journey, I've had the privilege of being continually blown away by the incredible polar research community and their unwavering support.

But my adventures don't stop at the icy landscapes of Antarctica; I've also joined expeditions to Greenland, Icelandic mountain glaciers, the European Alps, and New Zealand. After a decade abroad, I'm thrilled to be back in southern Germany, where I'm currently investigating glacier shear margins as part of the DFG-funded project "SOS-Antarctica."

If you're interested in diving into the world of icy research with me for a Bachelor's, Master's, or PhD thesis, don't hesitate to reach out! Let's brainstorm some cool (pun intended) research ideas!

Explore more: https://polarchristian.com/

Henry, Clara

Henry, Clara

The main focus of Claras research is numerical modelling of ice flow using the model Elmer/Ice. During her PhD at the University of Tübingen and the Max Planck Institute for Meteorology, she worked on improving our understanding of the role of pinning points in coastal ice-flow dynamics and the development of methods for model validation using observational data. She is now working as a postdoctoral researcher in a numerical analysis group at Stockholm University with the research goal of improving ice-flow model efficiency.

Visnjevic, Vjeran

Visnjevic, Vjeran

My research focuses on the interactions between climate and cryosphere. Trained as a geophysicist (Uni Zagreb), during my PhD (Uni Lausanne) I developed and applied a new inverse method to constrain past climates by combining ice flow modelling and geomorphological observations (mapped ice extents) in glaciated mountain ranges, focusing on the Alps and the Pyrenees during the Last Glacial Maximum (LGM). Working on this new approach I developed a strong interest in combining empirical data (geomorphological, proxy) and inverse modelling techniques in order to recover past climate signals. During my PhD I also learned how to write high-performance geocomputing algorithms on graphic cards (GPUs), which allows me to develop and apply new codes and approaches to large scale problems. It also opens opportunities to apply these skills to other fields of geoscience and modelling of Earth’s system.

As a postdoc (Uni Tübingen), together with my team we aim to develop an inverse approach to infer basal melt rates using radar isochrones as observational constraints. For our simulations we use the 3D full Stokes model Elmer/Ice. We hope that this approach will enable us to better constrain the magnitude and history of basal melting, which will give valuable input for ocean circulation and sea level rise modeling. Finally, our results will also guide the collection of new radar data (e.g., profile lines along vs. across-flow) in a way that ambiguities in interpreting the ice-shelf stratigraphy can be minimized.

Now at: https://www.climate.unibe.ch/ueber_uns/team/dr_visnjevic_vjeran/index_ger.html

Koch, Inka

Koch, Inka

Inka has participated in much field work of our group both in Antarctica and on alpine glaciers. Among other things she is a specialist in applied radio-glaciology. She has moved on to become a study coordinator of the global awareness programm at our University: https://uni-tuebingen.de/de/215290

Oraschewsi, Falk

Oraschewsi, Falk

I am a PhD student who is interested in the physical processes that control the dynamics of ice. This interest can be attributed to my background in Physics with a Bachelor from Heidelberg University and a Master from the University of Copenhagen, where I have already specialized in Geophysics and Glaciology. There I have studied how firn densification, which refers to the compaction of snow into glacial ice, is enhanced by dynamical processes. In my PhD (funded by the Studienstifung des dt. Volkes) I am now studying how anisotropy affects the dynamics of ice. Although it is known that the orientation of ice crystals strongly affects the ice dynamics and leads to a mechanical anisotropy, most ice sheet models still rely on an isotropic flow law, which might limit their ability to project the future evolution of the polar ice sheets. My research aims to better understand in which way anisotropy and ice dynamics intearct. Therefore, I develop new ground-based radar observation technics to investigate the internal structure and deformation of glaciers, in order to link those observations with the anisotropic crystal structure known from ice cores.

Appel, Erwin (Emeritus)

Appel, Erwin (Emeritus)

Prof. Dr. Erwin Appel
Hölderlinstr. 12
Raum: S 238a
72074 Tübingen
Ehemalige Arbeitsgruppe Geophysik

Ershadi, Reza

Ershadi, Reza

+49-(0)7071-29-73444

Raum 3R31, Geo- u. Umweltzentrum

I have a bachelor's degree in engineering and a master's degree in Applied and Environmental Geoscience (AEG). Geophysics is my favorite branch of science, and most of my geophysical experiences are related to mapping aquifers using Seismic and Electrical tomography. Joining this group as a Ph.D. student is helping me to discover another aspect of the beauty of Geophysics. #ICE, #RADAR, and #ROBOT are the keywords in my Ph.D. Finding a solution to describe ice fabric properties using polarimetric radar (ApRES) alongside with preparing and programming a four-wheeled rover for radar measurements in an Antarctic journey are my Ph.D. goals.

Past MSc / BSc Students

Past MSc / BSc Students

Past MSc / BSc Students:

N. Metzler (BSc, Geophysical investigation of an alluvial fan)

K. Ehlich (BSc, Passive seismics at a mofette site)

J. Hilgenberg (BSc, Modelling stepped-frequency continuous-wave radar)

F. Mattner (BSc, Ground penetrating radar study of a waste-disposal site)

J. Konietzko (MSc, Atmospheric influences in terrestrial radar interferometry)

P. Seibel (BSc, Characterization of basal roughness)

L. Bode (BSc, Tracking internal reflection horizons in East Antarctica)

Y. Zhou (MSc, Radar data analysis)

V. Lottes (BSc, Photogrammetry and Snow deposition)

S. Köppe (BSc, basal terraces on Antarctic ice shelves)

A. Arneke (BSc, marine geophysical analysis joint with Univ. Kiel)

H. Gerlach (BSc, geophysical characterisation of a waste-disposal site)

A. Hermann (MSc, numerical modelling)

M. Deppner (MSc, Inversion geoelectircs)

M. Zahn (BSc, GPR Antarctica)

E. Fast (BSc, GPR Iceland)

L. Naumann (BSc, self-build resistivity device)

G. Flinspach (BSc, Radar data analysis, Antarctica)

L. S. Muhle (MSc, Forward modelling GPR)

V. Richter (MSc, GPR Lauswiesen Site)

A. Patil (MSc, GPR Lauswiesen Site)

S. Ebeling (MSc, GRP detection of groundwater)

H. Spiegel (BSc, Radar data analysis Antarctica);

M. Erb (MSc, Seismics in the Ammer Valley)

J. Ching-Sheng Huan (MSc, GIS Analysis of ice-shelf channel morphology)

K. Chow (Msc, GNSS Analysis for an Antarctic outlet glacier, collab. with KIT Karlsruhe)

M. Martin (MSc, Airborne radar data analysis),

J. Loos (MSc, Numerical Flow Modelling of ice-shelf channel dynamics)

E. Seiert (MSc, Terrestrial Radar Interferometry of an alpine glacier)

M. Lieb (MSc. Finite Difference modeling of the isochronal ice structure)

S. Plath (MSc, Forward Modeling of radar data using exploding reflectors)

D. Ehmann (BSc, Deriving ice thickness from airborne radar)