GeoHype
Geomorphic and hydrologic implications of permafrost degradation in high-mountain environments
Rock glaciers are sensitive indicators of the current state and future fate of high-mountain permafrost. As mountain regions warm rapidly and precipitation patterns shift, understanding permafrost responses becomes essential for managing water resources and infrastructure. GeoHype combines remote sensing, geophysics, hydrology, and meteorology to decipher rock-glacier behavior at the Kaiserberg study site across multiple time scales.
Rock glacier surface changes
Surface changes on rock glaciers manifest as horizontal movement and vertical subsidence. Horizontal displacements reflect internal deformation processes, and creep rates typically increase as the permafrost body warms.
GeoHype investigates these movement rates across different time scales. Publicly available datasets from survey flights provide information on permafrost behaviour in the past decades. Since 2019, annual drone surveys provide high-resolution datasets. Kaiserberg rock glacier consists of two distinct parts, with the south-eastern lobe displaying notably faster movement rates.
Since 2023, time-lapse camera setups complement the data acquisition and allow for investigating short-term fluctuations in movement during the snow-free months.
Vertical surface changes can also be derived from the drone surveys. While some height variation results from movement that alters the local microtopography, extensive subsidence is largely driven by the melt of subsurface ice.
Subsurface and near-surface permafrost regime
A coarse active layer composed of rocks of varying sizes and air-filled voids insulates the underlying permafrost from direct atmospheric influence. Understanding how climatic signals propagate into the subsurface therefore requires dedicated subsurface investigations.
GeoHype employs geophysical methods such as Electrical Resistivity Tomography (ERT) to survey the subsurface. Very high resistivities typically indicate massive ice bodies or air-filled zones. The two distinct parts of Kaiserberg Rock Glacier differ markedly in ice content and distribution. Repeated surveys enable monitoring of changes in subsurface ice volume over time.
More direct investigations of how atmospheric climate signals propagate into the near-surface are enabled by multiple temperature loggers installed throughout the active layer. Measurements taken every 10 minutes allow correlations with meteorological events. Annual time series clearly show the insulating effect of the winter snow cover.
Rock glacier hydrology
Water stored in permafrost is likely to become more important than its glacial equivalent in the near future, as permafrost ice is insulated by the active layer and thus only indirectly affected by atmospheric warming. However, the amount and seasonal behaviour of discharge at rock-glacier springs remain poorly understood because meltwater from snow, glaciers, rain, and permafrost ice mixes before emerging at the surface.
A permanent gauging station downstream of the Kaiserberg rock glacier springs records water pressure and temperature. Complementary chemical analyses of the discharge are planned.
Publications
- Buchelt, S., Blöthe, J., Kuenzer, C., Schmitt, A., Ullmann, T., Philipp, M., Kneisel, C. (2023): Deciphering Small-Scale Seasonal Surface Dynamics of Rock Glaciers in the Central European Alps Using DInSAR Time Series. Remote Sensing, 15: https://dx.doi.org/10.3390/rs15122982
- Groh, T., and Blöthe, J.H. (2019): Rock Glacier Kinematics in the Kaunertal, Ötztal Alps, Austria, Geosciences, 9: 373: https://doi.org/10.3390/geosciences9090373
Contacts
Projektdaten
| Projektleitung | Dr. Eduart Weinbart |
| Projektmitarbeitende | Dr. Sofia Ramírez |
| Laufzeit | 08/2020 – 12/2014 |
| Finanzierung | BMBF |
| Kooperationspartner | Utrecht University Stellenbosch University |
| Webseite | www.projektname.de |