We present a unique dataset of repeated electrical resistivity tomography and long-term borehole temperature measurements to investigate the complex seasonal water flow in permafrost rockwalls. Our joint analysis shows that permafrost rocks are subject to enhanced pressurised water flow during the melt period. In addition to slow thermal heat conduction, permafrost rocks are subject to push-like warming events, favouring accelerated permafrost degradation and reduced rockwall stability.

The summertime thaw depth of permanently frozen ground (active layer thickness, ALT) is of critical importance for natural hazard management (e.g. rock avalanches), construction (foundation stability) and greenhouse gas emissions (decomposition rates) in permafrost regions. We presented the first analytical heat transport model for simulating ALT on borehole scale. Our results show that the ALT will likely increase by more than 50 % until 2050 at 3000 m a.s.l. in the European Alps.

Multispectral remote sensing imagery enables landslide detection and monitoring, but its applicability to time-critical early warning is rarely studied. We present a concept to operationalise its use for landslide early warning, aiming to extend lead time. We tested PlanetScope and unmanned aerial system images on a complex mass movement and compared processing times to historic benchmarks. Acquired data are within the forecasting window, indicating the feasibility for landslide early warning.

Climate warming is causing significant ice surface lowering even in the uppermost parts of alpine glaciers. Using terrestrial lidar, we quantify rockfall in freshly exposed cirque walls. During 6-year monitoring (2011–2017), an extensive dataset was established and over 600 rockfall events identified. Drastically increased rockfall activity following ice retreat can clearly be observed as 60 % of the rockfall volume detached from less than 10 m above the glacier surface.

Rockfall size and frequency in two deglaciating cirques in the Central Alps, Austria, is analysed based on 6-year rockwall monitoring with terrestrial lidar (2011–2017). The erosion rates derived from this dataset are very high due to a frequent occurrence of large rockfalls in freshly deglaciated areas. The results obtained are important for rockfall hazard assessments, as, in rockwalls affected by glacier retreat, historical rockfall patterns are not good predictors of future events.