For our session we invite contributions that either:
1. investigate present-day glacial and/or periglacial landforms, sediments and processes to describe the current state, to reconstruct past environmental conditions and to predict future scenarios in cold regions; or
2. have a Quaternary focus and aim at enhancing our understanding of past glacial, periglacial and paraglacial processes, also through the application of dating techniques.
Case studies that use a multi-disciplinary approach (e.g. field, laboratory and modelling techniques) and/or that highlight the interaction between the glacial, periglacial and paraglacial cryospheric components in cold regions are particularly welcome.
Orals: Mon, 4 May, 10:45–12:30 | Room G1
Much has improved about the glacial history of the British-Irish Ice Sheet (BIIS) during the Last Glacial Cycle (MIS 5d) thanks to rich data sets generated by the BRITICE Project. However, the south-west sector, between the Celtic Sea and Bristol Channel, is challenging because it is largely secured by marine evidence. However, a glacial landscape, preserved on the granitic island of Lundy, exhibits clear evidence of glacial over-printing with remnant transported glacial boulders, glacially-eroded bedrock surfaces, ice scoured tor stumps and erratic gravels. Lundy marks the intersection of ice flow across the eastern boundary of the Celtic Sea and southern extent of the Welsh Ice Cap at the Bristol Channel. The Celtic Sea transported one of the largest BIIS ice streams and thus has significant implications for understanding rapid deglaciation of large ice-sheets. Together with the Isles of Scilly, further south by ~125 km, both locations are strategically placed to pin down the southern extent of the history of the BIIS and answer the question – when during the Last Glacial Cycle did the BIIS overtop Lundy and if so, did it extend up through the Bristol Channel during the global LGM 27-23 ka yrs ago. Previous exposure ages ranging from 30-50 kyrs, from Lundy (Rolfe, 2012), notably on bedrock, point to a pre-MIS 3 glaciation (most likely MIS 4) ruling out the conclusion that LGM ice reached Lundy. Given that there is strong evidence (OSL and 10Be dating) for Scilly to have been glaciated during the LGM (Smedley et al 2017), which is also supported by BIIS modelling, debate surrounds assigning Lundy 10Be data to true exposure ages (Carr, 2017). The relatively large age spread possibly resulting from cosmogenic inheritance/erosional irregularities and pegmatite/beryl presence in Lundy granite (Mclintock, 1912) may complicate the interpretation of the exposure ages.
We have re-visited Lundy and collected 11 new samples comprising erratic boulders perched on polished bedrock, tor stumps and tops. The tor stumps (tops) would have been the least (most) persistent to preservation of inherited nuclides resetting . The new10Be exposure ages when compared to bedrock ages from Rolfe (2012) should confirm whether the timing of BIIS retreat at Lundy was before or during the LGM. Two OSL samples from cover sands over gravel will provide independent age control.
An interesting aspect of Lundy granite is the presence of beryl, topaz and other insoluble minerals (ie tourmaline). This required considerable care to quantify the intrinsic 9Be concentration. For example, in 3 quartz samples there was sufficient native 9Be to warrant zero addition of 9Be carrier. Not including a native 9Be contribution would underestimate exposure ages. However, the leaching of meteoric 10Be from these insoluble minerals during quartz dissolution is more of a concern and would result in over estimating exposure ages (Corbett, 2023). The new ages and impact of Lundy granite chemistry for cosmogenic dating will be represented.
Rolfe, QSR, v43, 2012
Carr, Proc. Geol. Assoc., v128, 2017
Mclintock, Mineral. Magazine, v16, 1912
Smedley, JQS, v32, 2017
Corbett, QG, v73, 2023
How to cite: Fink, D., Hughes, P., Rolfe, C., Bateman, M., Brown, A., and Simon, K.: Constraining decay of the British-Irish Ice Sheet on Lundy, Celtic Sea, during the Last Glacial Cycle , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11276, https://doi.org/10.5194/egusphere-egu26-11276, 2026.
Warming-driven melt impacts the landscape in glacierized catchments by altering bedrock erosion and the processes that mobilize subglacial sediment, affecting the delivery of sediment to downstream systems. Here, we synthesize insights from sediment export observations, together with numerical modeling experiments that evaluate ice motion, subglacial water flow, and sediment transport as they respond to change hydro-climatic conditions. The synthesis highlights timescale-dependent controls on sediment production, access, and mobilisation processes. During millennial-scale glacial retreat, steeper ice surfaces and warmer basal conditions increase glacier sliding, likely raising potential sediment production rates through bedrock abrasion. At decadal to annual scales, higher melt elevations allow water to access previously stored subglacial material further upglacier from the ice margin, so that sediment export may increase even as ice thins and sediment production rates fall. At event scales, such as during rapid discharge pulses from precipitation events, heatwaves, or floods, can strongly amplify transport capacity because subglacial conduits adjust slowly, causing intense variations in sediment transport capacity. These interacting processes imply that erosion rate estimates depend strongly on the duration of their observational period, potentially biasing observed rates toward pulses or hiatuses. Lastly, we discuss topics where the impact of greater hydro-climatic conditions on glacier erosion and sediment export is less well understood. These include the transport of sediment from ice sheets, along with the export of large sediment sizes as bedload. Finally, we outline how emerging in-situ sensing, novel geochronology, and next-generation models can better link climate forcing to sediment flux across timescales.
How to cite: Delaney, I., Margirier, A., Gevers, M., Jenkin, M., Leger, T., Vergara, I., Seguinot, J., Jouvet, G., Aitken, A. R. A., Lane, S. N., Herman, F., and King, G. E.: Links between ice dynamics, subglacial hydrology, and sediment flux from glaciers under increased melt conditions, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12165, https://doi.org/10.5194/egusphere-egu26-12165, 2026.
Present-day periglacial landscapes in mid-latitude mountain regions provide critical analogues for understanding both past cryospheric change and future responses of high-latitude systems to ongoing global warming trends. In the Scottish Highlands, long-lived seasonal ice patches have undergone increasingly frequent and extensive melt events in recent decades, reflecting broader patterns of cryosphere retreat documented across alpine and Arctic environments12. These rapidly changing features offer a testbed for examining how ice-ground interactions evolve during and after ice loss, and how their geomorphological and thermal signatures persist within the landscape34.
During the Oxford University Foundations Expedition to the Cairngorms, Scotland in August 2025, we conducted a grid-based thermal imaging survey of a recently ablated ice patch hollow called the Sphinx to investigate post-melt surface thermal behavior5. Thermal data was collected using a lightweight handheld infrared camera (HIKMICRO E01), enabling systematic acquisition of high-density surface temperature measurements across the former ice basin, its marginal slopes, meltwater channels, and adjacent control surfaces. Field observations, GPS locations, shading context, and surface characteristics were recorded alongside thermal measurements to support interpretations.
Measurements demonstrated that, within the historical ice patch hollow, the ground temperature averaged 11.52°C ± 0.60°C, 11.88°C ± 1.85°C colder than the adjacent terrain and 7.68°C ± 1.21°C colder than the ambient air temperature at the time of measurement. Hence, we found that coherent thermal anomalies persist following ice loss, which may reflect the former presence, thickness distribution, and melt history of the ice patch. A mosaic reconstruction of the thermal images demonstrates a clear thermal boundary coincident with the historical ice patch, indicating persistently lower surface temperatures relative to surrounding terrain despite the absence of surface ice.
By combining field-based thermal imaging with geomorphological context, this study demonstrates how present-day periglacial processes in a mid-latitude mountain setting can inform reconstructions of recent cryosphere change and provide analogues for future high-latitude warming scenarios. The Scotland campaign also serves as a methodological testbed for transferable thermal survey strategies applicable across cold-region environments. The expedition team aims to further explore this methodology in Western Greenland in summer 2026.
How to cite: Belhadfa, E., Francik, B. K., Fuenteslópez, C. V., and Lebedeva, S.: Persistent Surface Thermal Signatures Following Ice-Patch Ablation in the Scottish Highlands , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11795, https://doi.org/10.5194/egusphere-egu26-11795, 2026.
Ice-debris complexes are compound landforms, including glaciers, debris-covered glaciers and rock glaciers, that exist at the interface between the glacial, periglacial and paraglacial realms. These landforms are common in many mountain ranges on Earth, but the hydrological and geomorphological role of these ice-debris complexes in the context of deglaciating mountain environments is still not well understood. This is in part due to challenges arising from their position bridging different disciplines, categorisations, and research methodologies.
In this talk we present findings from our work based on in-situ investigations (including ground penetrating radar [GPR] and electrical resistivity tomography [ERT)] measurements) and multi-temporal high resolution remotely-sensed image analysis (based on historical aerial images, declassified Corona KH 4 images and contemporary data such as Pléiades satellite images) conducted on selected ice-debris complexes in the Tien Shan, Central Asia and further comparison with examples from the Pamirs, Andes and the European Alps.
Results show that the response of debris-covered glaciers, glacier-connected rock glaciers and talus-connected rock glaciers to climate change strongly differs, partly due to the different sources and amount of debris and ice inputs. The presence and distribution of massive ice varies across geomorphic units and is linked to the types of glacial-periglacial interaction. For example, we identify a significant amount of ice buried beneath debris cover in glacier forefields in transition to rock glaciers and in the glacier-connected rock glacier parts. Debris supply is important in controlling the development and flow activity of the morphological units. The response of rock glaciers to climate change is heterogenous with overall increasing velocities and on average only slight surface elevation changes. Glacier-connected rock glaciers flow on average faster than talus-connected rock glaciers. DEM differencing reveals slight increases in surface elevation at the rock glacier termini while debris-covered glaciers show on average a clear signal of surface lowering and decreasing velocities. This highlights the importance of understanding of the debris-sources and the interplay between the glacial and periglacial components of the ice-debris complexes when considering the hydrological and geomorphic role of these landforms.
How to cite: Bolch, T., Wood, E., Sun, Z., Falaschi, D., Bhattacharya, A., Robson, B., Kapitsa, V., and Schrott, L.: Characteristics and evolution of ice-debris complexes in deglaciating mountain environments investigated by remote sensing and in-situ surveys, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19000, https://doi.org/10.5194/egusphere-egu26-19000, 2026.
Sixteen uncrewed aerial vehicle (UAV) surveys were conducted along a 2.5 km stretch of coastline of Isbjørnhamna, Hornsund, Svalbard during summer months between 2018 and 2025 to quantify topographic change within a gravel beach neighboring the Polish Polar Station (PPS) from days to years. Spectral wave model of Herman et al. (2025) was used to extract hourly nearshore significant wave height, peak period, energy period and wave energy flux. The model was validated against observational data of Swirad et al. (2023). Storms were extracted as events when significant wave height exceeded 95th percentile. Near-daily high-resolution ice/open water maps of Swirad et al. (2024) were used to create timeseries of ice coverage in the main basin of Hornsund and in Isbjørnhamna. Hourly wave runup was calculated for 10 m alongshore blocks using wave parameters, beach topography and an empirical runup formula developed by Poate et al. (2016) for gravel beaches. Wave runup combined with water level was used to extract timing of wave overtopping and coastal flooding.
We observed a great inter-annual variability in wave and ice conditions with the icy 2019/20 and 2021/22, the stormy 2018/19, 2020/21 and 2022/23, and the moderate 2023/24 and 2024/25. There was a great variability in volumetric coastal change with near-zero change after 7 years. Erosion focused in some hotspots, notably the vicinity of the PPS infrastructure, while the eastern part of the analysed beach experienced net deposition. At the sub-monthly to monthly scales high rates of coastal change were related to beach erosion by moving growlers, development of beach cusps, melting of ice buried under beach sediments and hydrological processes.
References:
Herman A., Swirad Z.M. & Moskalik M. 2025. Increased exposure of the shores of Hornsund (Svalbard) to wave action due to a rapid shift in sea ice conditions. Elementa: Science of the Anthropocene 13(1): 00067. https://doi.org/10.1525/elementa.2024.00067
Poate T.G., McCall R.T. & Masselink G. 2016. A new parameterisation for runup on gravel beaches. Coastal Engineering 117: 176–190. https://doi.org/10.1016/j.coastaleng.2016.08.003
Swirad Z.M., Moskalik M. & Herman, A. 2023. Wind wave and water level dataset for Hornsund, Svalbard (2013–2021). Earth System Science Data: 15, 2623-2633. https://doi.org/10.5194/essd-15-2623-2023
Swirad Z.M., Johansson A.M. & Malnes E. 2024. Extent, duration and timing of the sea ice cover in Hornsund, Svalbard, from 2014–2023. The Cryosphere 18: 895-910. https://doi.org/10.5194/tc-18-895-2024
How to cite: Swirad, Z., Herman, A., and Moskalik, M.: Sub-monthly to inter-annual Arctic gravel beach change and controlling factors, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2311, https://doi.org/10.5194/egusphere-egu26-2311, 2026.
Climate reconstructions across Quaternary glacial cycles are limited in the southern mid-latitudes by a scarcity of terrestrial records. The Falkland Islands (~51°S) offer a key location for addressing this gap. Falklands block streams or ‘stone runs’ are among the most striking and enigmatic landforms on Earth but, despite over a century of study, their origin, and the role of Quaternary climate change, remains debated. We present new constraints on stone run formation using transects of cosmogenic Be-10 and Al-26 measurements. Twenty-six dual-isotopic exposure ages reveal altitudinal patterns that test two competing models: (1) formation during warm, tropical Tertiary conditions, with minimal Quaternary modification; or (2) production and transport under intensely cold, periglacial conditions entirely within the Quaternary. Our results also inform lingering questions about glacier extent and associated climate reconstructions. Falklands stone runs are arguably the most extensive and best-developed blockfield landscapes globally, providing an ideal testbed for examining formation. Our findings advance understanding of long-term blockfield evolution in unglaciated terrain, with implications for similar landscapes worldwide.
How to cite: Darvill, C. and Bentley, M.: Testing models of Falkland Islands Stone Run formation using cosmogenic nuclide exposure dating, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7140, https://doi.org/10.5194/egusphere-egu26-7140, 2026.
The rapid melting of alpine glaciers is expected to make subsurface ice, including that stored in periglacial formations like rock glaciers (RGs), an important shallow groundwater source for the downstream areas. However, many open questions remain about the ice volume in RGs, its melting rates, hydrological importance, and the quality of water flowing from RGs. This study aims to: i) characterize the geochemistry of RG springs, and ii) assess the variability of environmental tracers in spring waters downstream of RGs with different degree of activity.
We studied springs from intact (ice-embedding) and relict (without ice) RGs, as well as reference springs not influenced by RGs, in six mountain catchments of the Eastern Italian Alps. Sampling campaigns were carried out during two years with different snow and hydrometeorological conditions. While the hydrologic year 2023/2024 was characterized by higher snow cover accumulation and duration, the year 2024/2025 had a shorter accumulation season and most catchments were snow free already in June.
During summer 2024 and 2025, from late June to late September, we conducted sampling campaigns to measure spring water temperature, electrical conductivity (EC), pH, and collect water samples for analyzing stable isotopes of hydrogen and oxygen, major ions, and trace elements. We used automatic samplers to collect samples every 48 hours from one intact RG spring and one relict RG spring to study the temporal dynamics of different tracers.
Springs downstream of relict RGs exhibited lower EC than those from intact RGs. A seasonal isotopic enrichment was observed, likely due to decreasing snowmelt contribution. This seasonal enrichment was more pronounced at higher elevations. Intact RG springs had higher EC and sulphate concentrations compared to relict RGs and reference springs, especially in late summer (September) and in areas underlain by acidic metamorphic rocks (micashists). Water samples collected in 2025 from intact RG springs exhibited higher EC and ion concentrations than those collected in 2024. This contrast underscores the role of seasonal snow and snowmelt in the dilution of solutes released in high-elevation areas, where subsurface ice is likely present.
These initial findings reveal significant geochemical differences between springs from intact RGs and those from relict RGs or reference sites. At some intact RG springs nichel, manganese and sulphate concentrations are not suitable for drinking water, suggesting potential issues for human consumption.
These preliminary results contribute to the limited knowledge of RGs spring water chemistry, stimulating further investigation also including biogeochemical processes eventually involved in the rock-water interface.
This study was carried out within the project PRIN 2022 “SUBSURFICE – Ecohydrological and environmental significance of subsurface ice in alpine catchments” (code no. 2022AL7WKC, CUP: C53D23002020006), which received funding from the European Union NRRP (Mission 4, Component 2, Investment 1.1, D.D. 104 2/2/2022).
How to cite: Marin, E., Carturan, L., Marchina, C., Casentini, B., Guyennon, N., Marziali, L., Musazzi, S., Seppi, R., Zumiani, M., Brighenti, S., Colombo, N., Salerno, F., and Zuecco, G.: Tracer characterization of rock glaciers spring waters in the Eastern Italian Alps, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13525, https://doi.org/10.5194/egusphere-egu26-13525, 2026.
Cryosphere degradation due to climate change results in increased sediment availability, mobilization, and transport (Knight & Harrison, 2012; Lane et al., 2017; Micheletti & Lane, 2016; Beel et al., 2020; Li et al., 2021a; Zhang et al., 2021; Syvitski et al., 2022; Zhang, 2022). The change in magnitude and timing of water delivery and sediment transport alters river patterns (Lafrenière & Lamoureux, 2019; Fortier et al., 2007), such as via increasing channelization (Liljedahl et al., 2016; Li et al., 2021a; Chartrand et al., 2023). Despite the obvious signs of landscape transformation by rivers, the effects of climate change on High Arctic fluvial incision and sediment transport remain poorly quantified due to limited understanding of how thawing substrate, water availability, and erodibility interact.
Although frozen landscapes are expected to erode slower than their temperate counterparts, Eschenfelder et al. (in review) found that frozen riverbeds may erode faster. In their laboratory flume experiments, they observe injections of surface water into a frozen bed of uniform-sized spherical glass beads (D50 of ~1.9 mm), delivering heat and momentum fluxes to the thaw front. This increased subsurface melting and drove development of pressure gradients which enhanced surface erosion. They argue that later in the thaw season, when the upper layer of the bed has thawed in a more homogeneous fashion, water injections into the bed are physically accommodated and hence do not contribute to elevated surface erosion.
The glass bead substrate of Eschenfelder’s experiments has a high porosity (p = 0.4) and permeability, supporting significant hyporheic flow. However, natural sediments vary in size and composition, altering porosity and permeability. Furthermore, sediment size variability affects thawing rate (Gatto, 1995; Costard et al., 2003, 2014) and erosion rate (Einstein, 1950, Mitchener & Torfs, 1996; McCarron et al., 2019; van Rijn, 2020; de Lange et al., 2024).
In the proposed follow-up experiments, we plan to use various mixtures of glass beads (D50 = 0.88, 1.9 and 4.1 mm), and natural sediments, to alter porosity and permeability. The natural sediment distribution will be scaled to reflect substrate compositions observed during past field campaigns to the Canadian Arctic. We hypothesise that, if these water injections into the bed are still present in lower porosity sediments, fine grained beds will erode slower than courser grained beds, despite a lower threshold of motion. Furthermore, experiments with multiple freeze-thaw cycles will be performed, allowing assessment of a potential positive feedback loop where past-seasons’ thaw front undulations and surface topography can impact current season’s flow patterns – imparting “memory” onto the landscape.
With these experiments we will assess erosional mechanisms in a variety of grain sizes, allowing us to further explore the mechanisms of erosion in frozen riverbeds, ultimately aiding the understanding of spatial variability in channel incision in the field.
How to cite: de Lange, S., Eschenfelder, J., and Chartrand, S.: Erodibility of frozen riverbed sediments, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-4125, https://doi.org/10.5194/egusphere-egu26-4125, 2026.
Permafrost is one of the main components of the cryosphere. Due to global warming, water frozen reservoir shrinking and a large number of natural hazards (debris flows, water quality deterioration, etc.) related to permafrost degradation are increasing. The permafrost mapping of the Gaizi River Basin located in the East Pamir where the significant Karakoram Highway traverses was important for understanding the situation of its water resource and related hazards. Three machine learning models (Artificial Neural Network, ANN; Random Forest, RF; Extreme Gradient Boosting, XGBoost), were trained to generate permafrost probability distribution based on rock glaciers from Chinese Gaofen-1. Rock glaciers are commonly used as direct indicators of mountain permafrost distribution, particularly in alpine regions with limited in-situ data. Sixteen independent factors were used for permafrost distribution mapping that includes elevation, aspect, slope, solar radiation, topographic roughness index, topographic wetness index, profile curvature, distance from rivers, distance to glaciers, distance to water bodies, geology, fault density, LULC, NDVI, precipitation, temperature difference. The performances of the models have been evaluated by the area under the receiver operating characteristic curve (AUROC) and by known rock glaciers. Random Forest outperformed other two models, with Receiver Operating Characteristic curve values of 0.97. The permafrost map covers almost all the rock glaciers (98%), which also shows the permafrost map is reasonable. The permafrost distribution covers 1853 km2, about 16.81% of the total river basin, mainly between 3233 and 5026 m elevation. The results could be used as baseline information for studying the impact of permafrost degradation and its related hazards because of climate warming, which threaten the Karakoram Highway.
How to cite: Liu, Y.: Permafrost distribution mapping using rock glaciers data and machine learning models in the Gaizi River Basin, China, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3822, https://doi.org/10.5194/egusphere-egu26-3822, 2026.
Posters on site: Tue, 5 May, 10:45–12:30 | Hall X3
Hillslopes in the Canadian High Arctic can express curious quasi-linear sorted stripe patterns, physically resembling rills but with no obvious evidence of active particle transport via sustained surface water flows following rainfall or snowmelt. This motivates several questions which at present are little explored. First, how do the physical characteristics of the pattern vary down the hillslope in response to changing hillslope geomorphology (e.g. slope, elevation, etc.)? Second, what mechanism(s) causes sorted stripe patterns to initiate and develop, and what are the roles of freeze-thaw, granular, and fluid-flow-driven processes? Several attempts have been made to model the formation of sorted stripe patterns using rules-based approaches, or analytical models derived from these rules; however, a comprehensive physical model of sorted stripe formation has yet to be developed, and we currently lack even a characterization of how the pattern is distributed across a hillslope.
Here, we present a characterization of the sorted stripe patterning found on a hillslope on Tallurutit (Devon Island), Nunavut and examine topographic controls of hillslope track characteristics. By analyzing topographic lidar data, we find that there is not one preferred cross- or downslope spacing of the stripes; rather, the size and shape of stripes varies down the hillslope. This alludes to the idea that there are several processes at work to form hillslope sorted stripe patterns. We present a physical model of stripe formation involving initial fracturing of the hill due to thermal stresses, heaving from ice lens growth, and mobilization of stones due to the creation of critically-steep topographic gradients and ice needle formation. We motivate this model using the characterization of the sorted stripe pattern distribution, field observations, and an analysis of thermal and tensional stresses.
How to cite: Johnson, G. E., Chartrand, S. M., and Jellinek, A. M.: A Physical Model of Permafrost Sorted Stripe Formation in the Canadian High Arctic, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5849, https://doi.org/10.5194/egusphere-egu26-5849, 2026.
Frost weathering is a fundamental process controlling bedrock fracturing and rockfall activity in alpine environments, and its understanding requires evaluating the influence of snow cover on the thermal distribution at the bedrock surface (Matsuoka and Murton, 2008; Eckerstorfer et al., 2012; Haberkorn et al., 2017). In the Japanese Alps, characterized by heavy rainfall and snowfall, rock temperature data remain limited compared to the European Alps, which lie in the same mid-latitude zone as Japan. Moreover, long-term monitoring in the Japanese Alps has been confined to areas with relatively low snow accumulation (e.g., Matsuoka, 2019). In this study, we aim to clarify the conditions favorable for frost cracking in the heavy snow region by monitoring rock temperature, maximum snow depth, and snow-cover duration under various snow conditions on Mt. Hakuba (2,932 m a.s.l.) and Mt. Shakushi (2,812 m a.s.l.), located in the northern Japanese Alps.
From October 2021 to September 2025, we continuously monitored rock temperatures at depths mainly of 2 cm, 20 cm, and 40 cm, and locally down to a maximum depth of 120 cm. In addition, aerial surveys were conducted using a Cessna aircraft and UAVs. 3D point cloud models of rock slopes for different seasons were generated from aerial images using SfM/MVS analysis. Maximum snow depth at each sensor location was obtained from point cloud distance calculations between models representing the maximum snow accumulation and the snow-free period when bedrock is exposed. From the rock temperature data, several indices related to frost cracking were calculated, including annual freeze–thaw cycles (Matsuoka, 2002), freezing degree days, the duration of temperatures within the frost cracking window, and thermal gradient conditions (Kellerer-Pirklbauer, 2017). These indices were compared with interannual variations in snow depth and snow-cover duration.
In the results, snow-cover duration varied substantially between years, resulting in pronounced differences in frost cracking indices at each site. In addition, the height of snow cornices formed along ridges was greater than in heavy snow years, even when the overall snow cover duration was short, highlighting strong spatial heterogeneity in snow conditions near ridges. Although longer snow covers tended to raise winter rock temperatures, fractured bedrock sites showed lower temperatures and high freezing degree days. Future changes in frost cracking indices were calculated for each site based on various air-temperature warming scenarios, revealing markedly different trends depending on the scenario. These findings provide valuable insights for assessing present and future frost cracking potential in snow-rich alpine regions of Japan.
How to cite: Sugiyama, H. and Narama, C.: Four-year monitoring of rock temperature and snow conditions relevant to frost weathering in the northern Japanese Alps, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21081, https://doi.org/10.5194/egusphere-egu26-21081, 2026.
The link between rock glacier velocity and climatic forcing is well established in permafrost research, especially for rock glaciers. This understanding underpins the inclusion of rock glacier velocity as an associated parameter of the Essential Climate Variable “Permafrost” within the Global Climate Observing System since October 2022. In this context, the rock glacier velocity (commonly abbreviated as RGV) is defined as a spatially averaged interannual horizontal velocity time series related to a RG unit or a part of it. However, RGV does not invariably track climatic forcing in a simple, linear manner, which can obscure the climatic signal. In this study, we combine primarily multi-decadal RGV monitoring with long-term observations of ground surface and near-surface temperatures, as well as spring water temperatures, at two sites in the Hohe Tauern, Austrian Alps: the Dösen rock glacier (DOE) and the Hinteres Langtalkar rock glacier (HLK). Both are well-developed, typical alpine rock glaciers. Each features a dominant rock glacier spring that drains runoff from the landform and its contributing hydrologal catchment. Annual in-situ geodetic surveys began in 1995 (DOE) and 1999 (HLK). Ground surface and near-surface temperatures, along with several meteorological variables, have been monitored using miniature temperature loggers and standard meteorological sensors since 2006 at both sites. Spring water temperature monitoring started in 2016 at DOE and 2017 at HLK. Our results indicate a clear relationship, in part, between RGV and temperature (air, ground, water). However, this relationship weakens or disappears where geodetic points are not, or are only partially, representative of permafrost creep. Moreover, summer spring-water temperatures can be damped by heat exchange with internal ice, such that melt of the ice component buffers water peak temperatures. These findings underscore the importance of parallel, co-located monitoring of ground, water, and air temperatures (and other climatic parameters), alongside carefully designed geodetic sampling that targets zones of active permafrost creep.
How to cite: Kellerer-Pirklbauer, A. and Kaufmann, V.: Velocities of rock glaciers and their surface, near surface and hydrothermal regimes in the Austrian Alps: Clear signs of climate change?, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-21296, https://doi.org/10.5194/egusphere-egu26-21296, 2026.
In recent years, in situ monitoring of rock glacier displacement has become more challenging. Unstable slopes, higher probability of gravitational movement due to destabilization processes and rock fall are negatively impacting the accessibility of research sites. To maintain long-term time series, current monitoring techniques need to be adapted.
One example of a research site affected by this is Äußeres Hochebenkar rock glacier (46°50'0"N, 11°0'30"E, Ötztal Alps, Austria). The rock glacier has been subject to velocity measurements since 1938, making it one of the longest time series worldwide. Differential Global Navigation Satellite System (dGNSS) measurements are carried out since 2007. Aside minor data gaps, velocity data have been available at annual resolution since 1997 from four cross sections and a longitudinal profile. Each profile consists of 6 to 12 individual block positions.
For the majority of the time series, the flow velocity was hardly more than 1 m/a on average. Since 2018, an exponential increase of rock glacier motion has been observed in the lowest section, showing the destabilization of this part of the rock glacier. During the last three years, maximum displacement values at individual blocks increased from 20 m/a to almost 50 m/a in 2024 and 75 m/a in 2025.
Accessing the block profiles in the destabilized section to carry out dGNESS measurements has become challenging. To ensure the continuity of the time-series, UAV surveys have been incorporated in the monitoring program. In 2024 and 2025, multitemporal optical imagery was acquired in addition to dGNSS data. High-resolution othormosaics and digital elevation models were derived from the UAV imagery using Structure-from-Motion (SfM) photogrammetry techniques. This enables the calculation of spatially distributed displacement vectors over the whole rock glacier from multitemporal hillshades using image correlation algorithms and provides alternative observations of block displacement.
We present the displacement rates for the years 2024 and 2025 using the most recent workflow, comparing displacement rates from dGNSS measurements with those derived from mapping on high-resolution orthomosaics and image correlation of multitemporal hillshades. We show how dGNSS displacement can be complemented by and compared to UAV-based methods. We try to address the opportunities and uncertainties lying within these approaches for mountain landforms that are reacting quickly to environmental changes, assuming that more and more comparable cases will arise under current and future climatic conditions in high mountain regions.
How to cite: Hartig, A., Stocker-Waldhuber, M., Seiser, B., Hartl, L., and Fischer, A.: Long-term monitoring of rock glacier displacement - adaptation of methodology in response to new challenges, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19657, https://doi.org/10.5194/egusphere-egu26-19657, 2026.
As a result of climate change, temperatures in the European Alps are rising twice as fast compared to the global average, leading to unprecedented glacier retreat. Deglaciating alpine landscapes are considered extremely dynamic, evolving rapidly over space and time. One of the legacies of glacial activity is buried ice, also known as legacy or dead ice, describing ice that survives in the proglacial area for years to decades after glaciers retreat due to isolation from solar radiation and thermal effects by a sediment cover. Buried ice plays an important role in alpine basins, for instance, by providing long-term water storage. It is also likely to be an important influence on geomorphic processes, such as erosion. Quantification of erosion and deposition patterns from DEMs of difference (DoDs) may be problematic if DoDs do not distinguish geomorphic change from buried ice melt out. Such distinction is commonly omitted in studies, as ground-based geophysical measurements (e.g. Electrical Resistance Tomography, ERT) may need to be applied, extremely difficult given the challenges associated with accessing steep alpine terrain and the spatially extensive areas that may need to be measured. The extent of buried ice is therefore likely to be poorly estimated.
Satellite-based thermal remote sensing may provide a solution to this problem. Indeed, as an example, Interferometric SAR may be used to detect to a very high vertical precision the surface changes that suggest buried ice. However, the spatial resolution of such data may be inefficient when the surface changes are complex. Recent developments in drones and thermal sensors include compact drones with high quality thermal sensors, such as the DJI Mavic 3T. Drones have the benefit of (1) providing a higher spatial resolution compared to satellite thermal remote sensing, and (2) covering larger areas, compared to existing methods of buried ice detection, such as ERT.
In this research, a thermal drone was tested to identify buried ice in the Turtmann basin, a rapidly deglaciating Alpine valley in the Canton of Valais (southwestern Switzerland). Areas known to contain buried ice were surveyed. The assessment of the thermal images showed high coherence between cold patches on the images with known presence of buried ice.
This study highlights the potential for thermal drones in assessing and monitoring geomorphological processes in deglaciating environments, with a specific focus on buried ice. The results provide guidelines on equipment, survey design and execution, as well as data analysis for the use of thermal drones in alpine environments. Future research could focus on identifying approaches for validating the method for surveying areas with no prior knowledge on buried ice. There is a huge potential for the use of thermal drones that is yet to be explored.
How to cite: Repnik, L., Comiti, F., Gianini, M., Argentin, A.-L., Pitscheider, F., and Lane, S.: UAV-based thermal mapping for interpreting geomorphological processes in complex alpine environments, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-16984, https://doi.org/10.5194/egusphere-egu26-16984, 2026.
Central Svalbard experiences one of the fastest warming trends in the Arctic and local glaciers are consequently retreating fast leaving behind vast forefields. As the glacier is not in the vicinity, it is not the glaciers that transforms the forefield but the paraglacial processes that work to continuously reshape them.
Here, we studied paraglacial processes in the Hørbye forefield by quantifying changes in the glacier extent, forefield geomorphology and formation/ drainage of the kettle lakes of the Hørbye glacier since the last mapping conducted in 2009. Aerial photography, UAV-based orthophotos and DEMs and field observations were employed to interpret forefield development.
Results of the study show an increased forefield size of Hørbyebreen since the last mapping in 2009. The glacier has treated by 101237.4 m2. The area of the kettle lakes underwent a net decrease, with 68% of the total lakes either being drained, shrinking, or disappearing entirely due to sediment infilling from the fluvial plain. We also observed fluvial erosion of glacial landforms such as eskers.
Understanding these changes highlight the central role of paraglacial processes in post-retreat development. As the glacier moves to steeper topography, the retreat is expected to slow down, although the glacier will continue to provide enough water for intensive fluvial processes in the forefield. Widening of the sandur will lead to lateral erosion of the lakes in its vicinity. For the rest of the forefield, hydrological connectivity can reshape the existing network of lakes.
The changes observed between 2009-2024 show the retreat of the glacier front and changes in the geomorphological structures of the forefield. We observed a decline in the number of lakes and increase in the areal extent of the fluvial landforms.
How to cite: Nautiyal, D. and Kavan, J.: Exposed! Paraglacial Drama Unfolding at Hørbyebreen, Central Svalbard, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5863, https://doi.org/10.5194/egusphere-egu26-5863, 2026.
Despite major advances in paleoclimatology, key uncertainties remain regarding Holocene climate variability in the Southern Hemisphere, particularly concerning the evolution of the position and intensity of the Southern Westerly Winds (SWW) and their influence on high mountain cryospheric systems. The Subtropical Andes of Chile (30–35°S), located near the northern margin of SWW influence, offer an exceptional geomorphic record derived from glacial and periglacial ice in response to past climatic changes, and therefore suitable for reconstructing Holocene SWW variability.
Well-preserved glacial landforms, such as moraines, have been widely used to reconstruct past periods of increased moisture (e.g. Aguilar et al., 2022; Fernández-Navarro et al., 2023, 2024; García et al., 2024; Sagredo et al., 2017; Zech et al., 2017). In parallel, recent inventories show that the Subtropical Andes of Chile and Argentina host the most extensive periglacial belt in the Southern Hemisphere (Barcaza et al., 2017; DGA, 2022; Masiokas et al., 2020). Rock glaciers, indicative of sustained cold-ground and relatively arid conditions (Azócar & Brenning, 2010), therefore represent a major but still underutilized paleoclimatic archive. Although recent studies have demonstrated the potential of cosmogenic exposure dating of rock glaciers for paleoclimate reconstruction (e.g. Amschwand et al., 2021), this approach has remained unexplored in the Subtropical Andes until now.
Although glacial and periglacial landforms commonly coexist within the same catchments in the Subtropical Andes of Chile (e.g., Aguilar et al., 2022; Carraha et al., 2024), their temporal and morphostratigraphic relationships remain poorly constrained. Consequently, the timing and climatic drivers of glacial and periglacial phases are still mostly unknown (García et al., 2024; Jones et al., 2019), limiting our understanding of the Holocene paleoclimate and its cause. Here we present new 10Be cosmogenic exposure ages from moraines and surface blocks on multi-lobate rock glaciers in the Piedra Valley (30°S) to help constrain the timing and extent of periglaciaton of this valley after the LGM and into the Holocene. This combined glacial–periglacial chronological framework allows us to explore the timing of climatically controlled cryospheric response during the Holocene and their potential relationship with regional hydroclimatic variability. Our results contribute to a better understanding of cryosphere–climate interactions in mid-latitude mountain environments and provide new insights to test proposed hypothesis regarding glacial-periglacial transition at the end of the last ice age, as well as Holocene climate change in the subtropical southern latitudes.
How to cite: Carraha, J., García, J. L., Fernández-Navarro, H., and Amschwand, D.: Holocene climate variability as reconstructed from 10Be dated glacial and periglacial phases in the Subtropical Andes, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-5879, https://doi.org/10.5194/egusphere-egu26-5879, 2026.
Sedimentary archives from inner-Alpine settings predating the Last Glacial Maximum (LGM) are rare due to the strong erosional impact of LGM glaciers on these landscapes. In the Eastern Alps, a key site for reconstructing pre-LGM inner-Alpine environmental conditions is located near Innsbruck (Austria): the so-called Höttinger Breccia. This >1300m -thick sedimentary succession consists of basal lodgement till overlain by a thick sequence of alluvial to talus-slope deposits with intercalated aeolian and lacustrine sediments, capped by LGM moraine. Over a century ago, this succession also provided some of the first evidence for the multiple, cyclical nature of the ice ages.
Despite the significance of this site for reconstructing pre-LGM inner-Alpine environmental conditions, chronological constraints on these sediments remain limited. Previous optically stimulated luminescence (OSL) dating of quartz provided only minimum age estimates for the Höttinger Breccia because the quartz signals approached saturation. To overcome this limitation, this study applies infrared-stimulated luminescence (IRSL) dating to feldspar, as the IRSL signal saturates at much higher doses than the quartz OSL signal, thereby enabling dating further back in time. We exploit a range of post-IR IRSL (pIRIR) feldspar signals at stimulation temperatures from 110°C to 290°C to systematically investigate feldspar-related issues of anomalous fading and partial bleaching. We (i) present an optimized dating protocol that identifies the IRSL signal providing the best trade-off between signal stability and bleachability; (ii) report preliminary age estimates obtained from samples taken at various stratigraphic depths within the Höttinger Breccia succession; and (iii) integrate these age estimates into a 3D model of the sedimentary succession.
This combined chronological and spatial framework provides a basis for reconstructing Mid Pleistocene paleoenvironmental conditions in an inner-Alpine valley that otherwise preserves almost no geomorphic record of pre-LGM paleoclimate variability.
How to cite: Drexler, M., Sanders, D., and Meyer, M. C.: Luminescence dating and 3D modelling of a Mid Pleistocene inner-alpine alluvial-talus succession, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-10579, https://doi.org/10.5194/egusphere-egu26-10579, 2026.
Supraglacial landslides constitute an important component of glacier–landscape interactions, with the potential to influence glacier dynamics, mass balance, surface evolution, and sediment transport. From a geomorphological perspective, they contribute to the formation of large, anomalously positioned moraines and may, in some cases, facilitate the transition from glacier ice to rock glaciers. However, the glaciological and geomorphological significance of supraglacial landslides is highly variable and depends on landslide geometry, position relative to glacier accumulation and ablation zones, event timing, and the potential for long-term preservation of deposits.
This study investigates the spatial distribution and timing of large supraglacial landslides (>0.2 km² of deposits) across the Southern Andes. Landslide mapping was conducted using a multi-stage remote-sensing approach. First, potential supraglacial landslide locations were identified using high-resolution satellite imagery. Second, time series of medium-resolution satellite data (Landsat, ASTER, and Sentinel) were analysed to constrain the timing of individual events by estimating the occurrence window length (OWL), defined as the interval between the most recent image without a visible landslide and the oldest image in which the landslide deposit is observed. Third, morphometric characteristics were derived, and landslide locations were analysed in relation to glacier zones.
A total of 334 potential supraglacial landslides were identified, of which 198 deposits larger than 0.2 km² were detected on more than one satellite image between 1984 and 2025. For 59 of these landslides, sufficient time-series satellite imagery was available to constrain the OWL and thus approximate event timing. The results indicate that supraglacial landslides in the Southern Andes are substantially more frequent than previously recognised. The mapped inventory and timing constraints provide a basis for future analyses assessing the impact of individual landslides on glacier dynamics and their broader geomorphological significance.
This research was funded by the National Science Centre, Poland, project number 2021/42/E/ST10/00186
How to cite: Ewertowski, M. and Tomczyk, A.: Distribution of supraglacial landslides in the Southern Andes, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15168, https://doi.org/10.5194/egusphere-egu26-15168, 2026.
Crevasse squeeze ridges (CSRs) are landforms indicative of glacier surging and ice stream shut down. They form during fast ice flow, when high basal water pressures and extensional ice flow cause hydrofracturing in the base of the glacier and subsequent squeezing/injection of sediment into basal crevasses. When the fast ice flow phase ends, ice stagnates and down wasting of the ice surface occurs. If lateral support is maintained the sediment ridges are preserved as the glacier passively retreats. Geometries of these ridge networks can thus provide insights into subglacial conditions during phases of fast ice flow. This is important because the rapid movement of ice from areas of accumulation to ablation zones, during fast ice flow phases, exposes a greater area of ice to melting having long term impacts on the mass balance of these glaciers.
CSR characteristics have been inconsistently reported in the literature and in some cases have been misidentified. Here we present the first global dataset combining CSR information mined from the literature with new mapping and use this to define CSR characteristics in both surging and ice stream contexts as well as in terrestrial and marine settings. Using ArcGIS Pro, we map ridges from high resolution aerial imagery and digital elevation models, and extract metrics on ridge lengths, network density, and orientations in relation to ice flow direction. CSRs have been mapped at modern surge-type glaciers in Iceland and Svalbard, and in palaeo-landscapes in central Canada, the British Isles, and Northern Europe related to ice stream shutdown. Furthermore, we categorise the data into marine and terrestrial environments because CSRs are often better preserved in marine settings, due to the action of subaerial and meltwater erosional processes occurring on land.
This new dataset provides a representative understanding of CSR morphologies to allow better identification of the landform in the future, which will help to understand subglacial processes beneath fast-flowing ice masses. Understanding basal conditions in any glacial system is challenging due to the difficulties of acquiring direct measurements at the base of the glacier. CSRs represent these basal conditions and can therefore provide insights.
How to cite: Ranger, A., Rea, B., Spagnolo, M., Kurjanski, B., Newton, A., Pearce, D., and Lovell, H.: Mapping crevasse-squeeze ridges- defining characteristics for improved understanding and identification of these landforms, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18716, https://doi.org/10.5194/egusphere-egu26-18716, 2026.
In the context of ongoing glacier retreat and slope destabilisation, rockfalls in high-alpine cirque headwalls are becoming increasingly relevant and constitute an integral component of paraglacial process chains.
On the Höllentalferner (Wetterstein Mountains, Bavarian Alps), two prominent rockfall events occurred in recent years (2016 and 2024), depositing large amounts of debris onto the glacier surface and forming distinct supraglacial debris bodies. The aim of this study is a quantitative assessment of both events focusing on (i) quantifying the rockfall volumes using multi-temporal surface reconstructions and DoD-based estimates, (ii) assessing how supraglacial debris cover modifies glacier ablation by comparing bare-ice melt with melt beneath debris (i.e., differential ablation), and (iii) characterizing the spatio-temporal evolution of debris-body morphology (extent, thickness and internal redistribution) across consecutive observation epochs.
Methodologically, a multi-temporal DEM-of-Difference (DoD) approach is applied that combines, co-registers, and differences UAV/aerial-image-based SfM photogrammetry with airborne laser scanning (ALS) datasets. For this purpose, RTK-UAV surveys (2023 and 2025) are processed photogrammetrically into point clouds, DEMs and orthomosaics. The DEMs are aligned to stable terrain before DoDs are used to quantify elevation and volume changes.
First results indicate that volume estimates strongly depend on the chosen method: for the 2016 rockfall, estimates of approx. 10,410 m³ (extrapolation from bare-ice melt) and 15,510 m³ (Topo-to-Raster interpolation) are obtained, contrasted by a detachment volume of 5,206 m³. Interpolation-based DoD analyses yield epoch-specific volumes on the order of 19,443–31,519 m³, largely driven by differential ablation between debris-covered and adjacent bare-ice areas (and associated changes in the surrounding glacier surface). For the 2024 rockfall, current estimates amount to 20,171 m³ (extrapolation) and 10,128 m³ (detachment volume). Comparing bare-ice melt with melt beneath debris for the 2016 event indicates a pronounced insulating effect: between 2016 and 2018 (extrapolated), bare ice lowered by 4.3 m, whereas the debris-covered area lowered by only 0.8 m (differential ablation −3.5 m).
The findings highlight (i) the need for a multi-method framework to robustly constrain volumes and associated uncertainties, (ii) the key role of debris-driven melt/settlement processes for interpreting DoD signals on debris-covered glacier surfaces, and (iii) the potential of rockfalls deposits to locally delay glacier melt by supplying insulating debris.
How to cite: Kohlhage, T., Himmelstoss, T., Hagg, W., Stark, M., Heckmann, T., and Haas, F.: The evolution and insulation effect of two recent rockfalls on the Höllentalferner glacier in the Bavarian Alps: A multi-temporal analysis of volume and morphology using LiDAR and UAV data., EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-17096, https://doi.org/10.5194/egusphere-egu26-17096, 2026.
