Allgemein

A trip to the glacier is an opportunity to bring the algorithms to life. From the 4th to the 19th of July 2025, Danielle Gunders-Hunt (FAU Erlangen-Nürnberg, M³OCCA) and Valentin Marx (FAU Erlangen-Nürnberg, M³OCCA affiliated) were situated at the Jungfraujoch research station in Switzerland to collect radar measurements using custom-built radar systems.

This summer’s fieldwork took us to the Aletsch Glacier in Switzerland. We drove to Grindelwald on Thursday and met up with colleagues from RWTH Aachen and the University of Wuppertal, affiliated with the TRIPLE project. After an impressive gondola ride and train journey through the mountain, we arrived at the research station located at 3,454 m a.s.l.

The research station is home only to researchers and is managed by a couple who oversee the High Altitude Research Stations Jungfraujoch & Gornergrat. They showcased the fascinating equipment held permanently on the glacier, ranging from instruments measuring air constituents for climate change monitoring, to medical and biological experiments observing the influence of high altitude on organisms.

The next day we began with a guided tour led by a mountain guide to learn the basic rescue techniques and familiarize ourselves with the glacier terrain. Unstable weather in the first few days caused some delays, but we soon began carrying out our full set of measurements with the GPR sled.

Our goal was to evaluate our equipment in various walking formations to assess the efficiency of each imaging method. Different formations can leverage different algorithms to generate 2D or 3D images of the snow and firn layers, as well as crevasses hidden beneath the surface.

Both radar systems used during the campaign were developed in-house at the Institute of Microwaves and Photonics (LHFT), FAU Erlangen-Nürnberg. The first system was an impulse radar operating at a center frequency of 1.35 GHz. Impulse radar transmits short, broadband pulses and listens for echoes reflected from internal glacier boundaries—such as transitions between snow, firn, ice—or from embedded features like crevasses, air pockets or water inclusions. We then replaced the radar system with a frequency-modulated continuous wave (FMCW) radar, ramping between 0.7 and 4.7 GHz. Unlike impulse radar, FMCW continuously emits a frequency-modulated signal and compares the transmitted and received waves to measure the time delay and amplitude of returning echoes. This method offers improved sensitivity and resolution, especially for fine structures near the surface.

We are now looking forward to analyzing how each type of radar—together with its frequency and signal power—affects both the penetration depth and the resolution of subsurface glacial features.

The fieldwork was a rewarding collaborative experience. Working alongside the TRIPLE team, who were testing a hybrid radar and sonar based forefield reconnaissance system integrated into a melting probe, reaching 12 m beneath the surface, gave us valuable insights into subsurface structures which we hope to cross-validate with our radar results.

Beyond the scientific goals, sharing meals, challenges, and ideas made the high-altitude days both productive and memorable. Each evening, breathtaking sunsets from the Sphinx Observatory (3,570 m a.s.l.) reminded us how extraordinary our setting truly was—it felt like we were on top of the world!

This campaign wouldn’t have been possible without the support of Valentin Marx, Lukas Rechenberg, and Niklas Haberberger, as well as the remaining colleagues from the TRIPLE-FRS-2 project.

The M3OCCA project is generously funded by the Elitenetzwerk Bayern.

A much-awaited winter 2025 Aletsch expedition was carried out to attain repeat glaciological and geophysical measurements at locations similar to the winter 2024 Aletsch campaign. An expedition aimed to detect changes in firn stratigraphy and firn density over two consecutive years under the influence of regional climatic changes. This was achieved by using Ground Penetrating Radar (GPR) profiling across the two main accumulation zones of the Aletsch glacier. The GPR-based common mid-point (CMP) method was used to gather indirect firn density measurements. This was complemented by the deep firn core (nearly 20 m) at the upper part of the Ewigschneefeld, a shorter firn core (approximately 8 m) at the lower part of the Ewigschneefeld, and two snow pits at Jungfraufirn and the Ewigschneefeld.

This expedition is part of the M3OCCA international doctoral program (IDP) project SP2.3. The campaign was a collaborative effort of Paul Scherrer Institute (PSI), Bern, Switzerland, BAdW, Munich, and FAU Erlangen, Germany.

We appreciate the efforts of the firn core team, Dr. Theo Jenk, Michelle Worek (PhD), and Samuel Marending from Laboratory of Analytical Chemistry, PSI Bern, Switzerland, Dr. Christoph Mayer, Dr. Astrid Lambercht, and Akash Patil (PhD) from Department of Geodesy and Glaciology BAdW Munich, Germany, and Dr. Thorsten Seehaus and Dr. Alexander Groos from Institute of Geography FAU Erlangen, Germany.

We organized a one-day workshop on ‘How to give a good talk’.

The workshop covered various topics from Stage fright over Body Language to Humor in talks. The participants benefited a lot from the intensive feedback they received from their colleagues and the trainer.

Thank you again, Nae, for the great workshop!

Knowledge about permafrost distribution is critical for the assessment of rock mass stability. By installing rock surface temperature loggers we aim to create a model to explore the distribution of permafrost in the Ötztal Alps. Solar incoming radiation and air temperature are the main drivers of permafrost evolution. Therefore we picked diverse locations in height, aspect and slope for installing the loggers.

The field work took place on a wonderful sunny day on 6th of September 2023. We are happy that everything worked out as planned and we returned home from the mountains in a safe way with good new stories on our shoulders.