The glaciers in the world’s high mountain regions are important freshwater reservoirs, providing resources for drinking water, irrigation and hydropower. However, as a result of climate change, they are melting dramatically and causing sea levels to rise. This has been confirmed by a new international study, in which three researchers from the Institute of Geography were involved and which has now been published in the scientific journal Nature.

The study shows that glaciers have lost an average of 273 billion tons of ice per year since 2000, with an alarming increase in the last ten years. Over the entire period, more than 6,500 billion tons of glacier ice have been lost. This corresponds to a global sea level rise of 18 millimeters in the last two decades. However, there are clear regional differences in the change in glaciated areas: the loss of ice mass in the European Alps compared to the year 2000 is around 39%, while glaciers on the Antarctic islands have only lost 2% of their original mass. Overall, however, the worldwide melting of glaciated areas is now the second largest cause of global sea level rise, surpassed only by the warming of the oceans.

For the “Glacier Mass Balance Intercomparison Exercise” (GlaMBIE) by the European Space Agency ESA, 35 teams consisting of around 450 scientists from all over the world combined observations from field measurements and various satellite missions to create time series of global ice mass changes from 2000 to 2023. As the investigations were carried out using different measurement methods, the new GlaMBIE study not only provides a more detailed description of global and regional glacier development over the last two decades, but also enables a direct comparison of different research approaches. Prof. Dr. Matthias Braun, Dr. Thorsten Seehaus and Dr. Christian Sommer from the Institute of Geography contributed data and analyses on glacier elevation changes based on measurements from the German TanDEM-X satellite mission in the Andes, the European Alps and the Arctic.

Their research was funded by the German Research Foundation (DFG) and the German Aerospace Center (DLR). Prof. Braun coordinates the IDP M³OCCA. Dr. Seehaus leads a DFG Emmy-Noether funded research group that aims to better assess glacier changes and their impacts in the tropical Andes.

https://doi.org/10.1038/s41586-024-08545-z

Do you wonder what mechanism caused the massive rock avalanche at Piz Scerscen (Bernina, CH) in spring 2024 (link to DAV-report)? Read the paper: >here<.

Felix Pfluger (TUM, funded by M³OCCA) and colleagues investigated glacier changes, conducted fieldwork on permafrost at 3200 m asl, rock mechanical laboratory studies (Joseph Steinhauser as part of his Bachelor Thesis) and mechanical modeling on a slope scale to infer permafrost–glacier interactions and their implications for triggering high-volume rock slope failures. Using the Bliggspitze rock slide as a case study (Austria, Tyrol), we demonstrate a new type of rock slope failure mechanism triggered by the uplift of the cold–warm dividing line in polythermal alpine glaciers, a widespread and currently under-explored phenomenon in alpine environments worldwide. The publication features a holistic discussion on the role of meltwater and water infiltration/migration in bedrock enabling the buildup of hydrostatic pressure that eventually triggered the rock slide.

With this research, we advance our understanding of coupled processes in complex slope failures situated in the cryosphere.

It was realized as a joint collaboration with researchers from TUM, SLF, BOKU, and FAU.

Ground penetrating radar (GPR) is an effective tool in cryosphere and climate research, as it can provide detailed, non-invasive insights into ice thickness, internal structures, and subglacial conditions. This technology uncovers critical data on glacier dynamics and climate change impacts, enhancing our understanding of past, present, and future environmental shifts. In this contribution, the design and experimental verification of a lightweight, surface-based GPR platform intended for imaging glacial subsurface structures is presented. Therein, the system requirements for glaciological applications and the design implications for the developed platform and its components are described. In addition, a detailed overview of the utilized radar system, including the 3D-printed horn antennas and the localization concept, is provided. Furthermore, the imaging properties of the developed system are introduced, and the processing chain to retrieve subsurface images from the raw radar data using synthetic aperture radar concepts is presented. The platform was tested during a field campaign in March 2024 on the Jungfraufirn glacier in Switzerland. The data from this field campaign provide detailed imaging results of the glacier subsurface, including its stratification with high resolution and contrast. Moreover, a comparison of our rather broadband ultra-high frequency GPR measurements to the data acquired with a high-performance state-of-the-art low frequency GPR system is provided. Finally, this contribution concludes with current limitations and an outlook on future improvements.

https://ieeexplore.ieee.org/document/10669622

The regional climate of New Zealand’s South Island is shaped by the interaction of the Southern Hemisphere westerlies with the complex orography of the Southern Alps. Due to its isolated geographical setting in the south-west Pacific, the influence of the surrounding oceans on the atmospheric circulation is strong. Therefore, variations in sea surface temperature (SST) impact various spatial and temporal scales and are statistically detectable down to temperature anomalies and glacier mass changes in the high mountains of the Southern Alps. To enable future studies on the processes that govern the link between large-scale SST and local-scale high-mountain climate, we utilized dynamical downscaling with the Weather Research and Forecasting (WRF) model to produce a regional atmospheric modelling dataset for the South Island of New Zealand over a 16-year period between 2005 and 2020. The 2 km horizontal resolution ensures realistic representation of high-mountain topography and glaciers, as well as explicit simulation of convection. The dataset is extensively evaluated against observations, including weather station and satellite data, on both regional (in the inner domain) and local (on Brewster Glacier in the Southern Alps) scales. Variability in both atmospheric water content and near-surface meteorological conditions is well captured, with minor seasonal and spatial biases. The local high-mountain climate at Brewster Glacier, where land use and topographic model settings have been optimized, yields remarkable accuracy on both monthly and daily time scales. The data provide a valuable resource to researchers from various disciplines studying the local and regional impacts of climate variability on society, economies and ecosystems in New Zealand. The model output from the highest resolution model domain is available for download in daily temporal resolution from a public repository at the German Climate Computation Center (DKRZ) in Hamburg, Germany (Kropač et al., 2023; 16-year WRF simulation for the Southern Alps of New Zealand, World Data Center for Climate (WDCC) at DKRZ [data set], https://doi.org/10.26050/WDCC/NZ-PROXY_16yrWRF).

https://rmets.onlinelibrary.wiley.com/doi/10.1002/gdj3.263