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Ongoing global warming intensifies the degradation of mountainous permafrost. Permafrost thawing impacts landform evolution, reduces fresh water resources, enhances the potential of natural hazards, and thus has significant socio-economic impact. Electrical resistivity tomography (ERT) has been widely used to map the ice-containing permafrost by its resistivity contrast compared to the surrounding non-frozen medium. This study aims to reveal the effects of ongoing climate warming on alpine permafrost by repeating historical ERT and analysing the temporal changes in the resistivity distribution. In order to facilitate the measurements, we introduce and discuss the employment of textile electrodes. These newly developed electrodes significantly reduce working effort, are easy to deploy on blocky surfaces, and yield sufficiently low contact resistances. We analyse permafrost evolution on three periglacial landforms (two rock glaciers and one talus slope) in the Swiss and Austrian Alps by repeating historical surveys after periods of 10, 12, and 16 years, respectively. The resistivity values have been significantly reduced in ice-poor permafrost landforms at all study sites. Interestingly, resistivity values related to ice-rich permafrost in the studied active rock glacier partly increased during the studied time period. To explain this apparently counterintuitive (in view of increased resistivity) observation, geomorphological circumstances such as the relief and increased creeping velocity of the active rock glacier, are discussed by using additional remote sensing data. The present study highlights ice-poor permafrost degradation in the Alps resulting from ever-accelerating global warming.

Permafrost as a climate-sensitive parameter, its occurrence and distribution plays an important role in the observation of global warming. However, field-based permafrost distribution data and information on the subsurface ice content at the large area of the southern mountainous Tibetan Plateau (TP) is very sparse. Existing models based on boreholes and remote sensing approaches suggest permafrost probabilities for most of the Tibetan mountain ranges. Field data to validate permafrost models are generally lacking because access of the mountain regions in extreme altitudes is limited. The study provides geomorphological and geophysical field data from a north-orientated high-altitude catchment in the western Nyainqentanglha Range. Our multi-method-approach combines (A) geomorphological mapping data, (B) subsurface ice-occurrence derived from electrical resistivity tomography (ERT) data, and (C) multi-annual displacement rates from Interferometric Synthetic Aperture Radar (InSAR) analysis to assess the lower occurrence of the probable permafrost around 5400 m a.s.l. in the Qugaqie basin. Periglacial landforms such as rockglaciers and protalus ramparts are located in the periglacial zone from 5300–5600 a.s.l. The altitudinal periglacial landform distribution is supported by ERT data detecting ice-rich permafrost in a rockglacier at 5500 m a.s.l. and ice lenses around the rockglacier (5450 m a.s.l.). The highest, multiannual displacement rates up to 150 mm/y are observed typically on these rockglaciers. However, seasonality of rockglacier surface displacement like in other high mountain areas is missing. This study closes the gap of unknown state of periglacial features and potential permafrost occurrence in a high-elevated basin at the western Nyainqentanglha Range (Tibetan Plateau) and suppose – compared to other high mountain regions – a higher-elevated permafrost occurrence.

Climate change and the associated rise in air temperature have affected the Tibetan Plateau to a significantly stronger degree than the global average over the past decades. This has caused deglaciation, increased precipitation and permafrost degradation. The latter in particular is associated with increased slope instability and an increase in mass-wasting processes, which pose a danger to infrastructure in the vicinity. Interferometric synthetic aperture radar (InSAR) analysis is well suited to study the displacement patterns driven by permafrost processes, as they are on the order of millimeters to decimeters. The Nyainqêntanglha range on the Tibetan Plateau lacks high vegetation and features relatively thin snow cover in winter, allowing for continuous monitoring of those displacements throughout the year. The short revisit time of the Sentinel-1 constellation further reduces the risk of temporal decorrelation, making it possible to produce surface displacement models with good spatial coverage. We created three different surface displacement models to study heave and subsidence in the valleys, seasonally accelerated sliding and linear creep on the slopes. Flat regions at Nam Co are mostly stable on a multiannual scale but some experience subsidence. We observe a clear cycle of heave and subsidence in the valleys, where freezing of the active layer followed by subsequent thawing cause a vertical oscillation of the ground of up to a few centimeters, especially near streams and other water bodies. Most slopes of the area are unstable, with velocities of 8 to 17 mm yr−1. During the summer months surface displacement velocities more than double on most unstable slopes due to freeze–thaw processes driven by higher temperatures and increased precipitation. Specific landforms, most of which have been identified as rock glaciers, protalus ramparts or frozen moraines, reach velocities of up to 18 cm yr−1. Their movement shows little seasonal variation but a linear pattern indicating that their displacement is predominantly gravity-driven.

Rock glaciers are receiving increased attention as a potential source of water and indicator of climate change in periglacial landscapes. They consist of an ice‐debris mixture, which creeps downslope. Although rock glaciers are a wide‐spread feature on the Tibetan Plateau, characteristics such as its ice fraction are unknown as a superficial debris layer inhibits remote assessments. We investigate one rock glacier in the semiarid western Nyainqêntanglha range (WNR) with a multi‐method approach, which combines geophysical, geological and geomorphological field investigations with remote sensing techniques. Long‐term kinematics of the rock glacier are detected by 4‐year InSAR time series analysis. The ice content and the active layer are examined by electrical resistivity tomography, ground penetrating radar, and environmental seismology. Short‐term activity (11‐days) is captured by a seismic network. Clast analysis shows a sorting of the rock glacier's debris. The rock glacier has three zones, which are defined by the following characteristics: (a) Two predominant lithology types are preserved separately in the superficial debris patterns, (b) heterogeneous kinematics and seismic activity, and (c) distinct ice fractions. Conceptually, the studied rock glacier is discussed as an endmember of the glacier—debris‐covered glacier—rock glacier continuum. This, in turn, can be linked to its location on the semiarid lee‐side of the mountain range against the Indian summer monsoon. Geologically preconditioned and glacially overprinted, the studied rock glacier is suggested to be a recurring example for similar rock glaciers in the WNR. This study highlights how geology, topography and climate influence rock glacier characteristics and development., Plain Language Summary: Climate change has begun to impact all regions of our planet. In cold regions, such as high‐mountain areas, rising temperatures lead to massive melting of glaciers. Besides this evident loss of ice, permafrost, a long‐term ice resource hidden in the subsurface, has started to thaw. Rock glaciers as visible permafrost‐related landforms consist of an ice‐debris mixture, which makes them creep downslope. Due to this movement and their recognizable shape, rock glaciers are permafrost indicators in high‐mountain areas. We investigate one rock glacier in the western Nyaingêntanglha Range (Tibetan Plateau) using field and remote sensing methods to understand its development and to know the current state of its ice core. Our main outcome is, that the heterogeneous creeping behavior, the properties of the debris cover as well as the internal distribution of ice are the results of a continuous development from a glacier into today's rock glacier. In particular, the high ice content in particular sections points to such a glacial precondition. The debris layer covering the internal ice attenuates the effect of climate warming. This makes the rock glacier and similar rock glaciers found in the northern part of the mountain range important future water resources for the semiarid region., Key Points: Geophysical and remote sensing methods in concert reveal the morphostructure, ice fraction, and kinematics of the studied rock glacier. Rock glacier characteristics are controlled by geology, topography and climate on the Tibetan Plateau. The studied rock glacier is conceptually interpreted as the endmember of a glacier—debris‐covered glacier—rock glacier continuum., Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659