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The Rock Glacier Inventories and Kinematics community (RGIK) has defined standards for generating Rock Glacier Inventories (RoGI). In the framework of the European Space Agency Climate Change Initiative for Permafrost (ESA CCI Permafrost), we set up a multi-operator mapping exercise in 12 areas around the world. Each RoGI team was composed of five to ten operators, involving 41 persons in total. Each operator performed similar steps following the RGIK guidelines (RGIK, 2023a) and using a similar QGIS tool. The individual results were compared and combined after common meetings to agree on the final consensus-based solutions. In total, 337 "certain" rock glaciers have been identified and characterised, and 222 additional landforms have been identified as "uncertain" rock glaciers. The dataset consists of three GeoPackage files for each area: 1) the Primary Markers (PM) locating and characterising the identified Rock Glacier Units (RGU), 2) the Moving Areas (MA) delineating areas with surface movement associated with the rock glacier creep, based on spaceborne Interferometric Synthetic Aperture Radar (InSAR), and 3) the Geomorphological Outlines (GO) delineating the restricted and extended RGU boundaries. Here we present the procedure for generating consensus-based RoGI, describe the data properties, highlight their value and limitations, and discuss potential applications. The final PM/MA/GO dataset is available on Zenodo (Rouyet et al., 2024; https://doi.org/10.5281/zenodo.14501399). The GeoPackage (gpkg) templates for performing similar RoGI in other areas, and exercises based on the QGIS tool, are available on the RGIK website (https://www.rgik.org). [ABSTRACT FROM AUTHOR]

This study presents monitoring data of a debris flow event in the Central Italian Alps. The debris flow occurred on August 16, 2021 in the Blè basin (Val Camonica valley, Lombardia Region) and was recorded by a monitoring station installed just few weeks before. The monitoring system was deployed to document the hydrologic response of the catchment to rainfall, and was designed to be lightweight, relatively cheap, and easy to deploy in the field. To this purpose, we combined video cameras with geophysical sensors (geophones and infrasound) and optimized the power supply system. The data recorded during the event allowed to identify the triggering rainfall, document the flow behaviour, and estimate surface flow velocity and flow rate using Particle Image Velocimetry algorithms. Moreover, the seismic signal generated by the debris flow revealed a peculiar frequency spectrum compared to regular streamflow. These results show that even a relatively simple monitoring system may provide valuable data on real debris flow events.

In dry southwestern South Tyrol, Italy, rock glaciers are dominant landforms of the high-mountain cryosphere. Their spatial distribution and degree of activity hold critical information on the current state of discontinuous permafrost and consequently on the response potential to climate warming. Traditional geomorphologic mapping, however, owing to the qualitative expert-based nature, typically displays a high degree of uncertainty and variability among operators with respect to the dynamic classification of intact (permafrost-bearing) and relict (permafrost-devoid) rock glaciers. This limits the reliability of geomorphologic rock glacier inventories for basic and applied purposes. To address this limitation, (i) we conduct a systematic evaluation of the improvements that synthetic aperture radar interferometry (InSAR) can afford to the detection and dynamic classification of rock glaciers and (ii) build an integrated inventory that combines the strengths of geomorphologic- and InSAR-based approaches. To exploit fully InSAR-based information towards a better understanding of the topo-climatic conditions that sustain creeping permafrost, we further explore how velocity and the spatial distribution of moving areas (MAs) within rock glaciers may vary as a function of simple topographic variables known to exert first-order controls on incoming solar radiation, such as elevation and aspect. Starting from a geomorphologic inventory (n=789), we characterize the kinematics of InSAR-based MAs and the relevant hosting rock glaciers on 36 Sentinel-1 interferograms in the 2018–2019 period. With respect to the original inventory, InSAR analysis allowed us to identify 14 previously undetected rock glaciers. Further, it confirmed that 246 (76 %) landforms, originally interpreted as intact, do exhibit detectable movement (i.e., ≥1 cm yr -1) and that 270 (60 %) of the relict labeled counterparts do not, whereas 144 (18 %) were kinematically undefined due to decorrelation. Most importantly, InSAR proved critical for reclassifying 121 (15 %) rock glaciers, clarifying that 41 (13 %) of those interpreted as being intact do not exhibit detectable movement and that 80 (17 %) of the original relict ones do move. Reclassification (i) allowed us to identify a cluster of intact rock glaciers below 2000 m a.s.l. associated with positive mean annual air temperature (MAAT), and (ii) by increasing the altitudinal overlap between intact and relict rock glaciers, it depicts a broad transition belt in the aspect–elevation space, which varies from 50 m on west-facing slopes to 500 m on easterly ones. This finding deteriorates the significance of elevation and aspect as topographic proxies for modeling permafrost occurrence and highlights the importance of using InSAR to inform such models. From a process-oriented standpoint, InSAR information proves fundamental for imaging how this altitudinal transition manifests through changing rates and styles of rock glacier surface deformation. Specifically, we find that, as rock glaciers move faster, an increasingly larger proportion of their surface becomes kinematically involved (i.e., percent MA cover) and that this proportion increases with elevation up to 2600–2800 m, beyond which an inflection occurs and consistent average values are attained. Considering that the inflection falls between the -1 and -2 °C MAAT – the lower boundary for discontinuous permafrost – and is independent of slope gradient, we conclude that this altitudinal pattern represents a geomorphic signature: the dynamic expression of increasing permafrost distribution, from sporadic to discontinuous. [ABSTRACT FROM AUTHOR]

In dry southwestern South Tyrol, Italy, rock glaciers are dominant landforms of the high-mountain cryosphere. Their spatial distribution and degree of activity hold critical information on the past and current state of discontinuous permafrost, and consequently on response potential to climate warming. Traditional geomorphologic mapping, however, owing to the qualitative expert-based nature, typically displays a high degree of uncertainty and variability among operators with respect to the dynamic classification of intact (permafrost bearing) and relict (permafrost devoid) rock glaciers. This limits the reliability of geomorphologic rock glacier inventories for basic and applied purposes. To address this limitation: (i) we conduct a systematic evaluation of the improvements that InSAR-based information can afford to the detection and dynamic classification of rock glaciers; and (ii) build an integrated inventory that wishes to combine the strengths of geomorphologic- and InSAR-based approaches. To exploit fully InSAR-based information towards a better understanding of the topo-climatic conditions that sustain creeping permafrost, we further explore how velocity and the spatial distribution of moving areas (MAs) within rock glaciers may vary as a function of simple topographic variables known to exert first-order controls on incoming solar radiation, such as elevation and aspect. Starting from the compilation of a geomorphologic inventory (n = 789), we characterize the kinematics of InSAR-based MAs and the relevant hosting rock glaciers on thirty-six Sentinel-1 interferograms computed over 6-through 342-day baselines in the 2018-19 period. With respect to the original inventory, InSAR analysis allowed identifying 14 previously undetected rock glaciers. Further, it confirmed that 246 (76%) landforms, originally interpreted as intact, do exhibit detectable movement (i.e., =1 cm yr-1), and that 270 (60%) of the relict labelled counterparts do not, whereas 144 (18 %) resulted kinematically undefined due to decorrelation. Most importantly, InSAR proved critical for reclassifying 121 (15%) rock glaciers, clarifying that 41 (13%) of those interpreted as intact, do not exhibit detectable movement, and that 80 (17%) of the original relict ones do actually move. Reclassification, by increasing the altitudinal overlap between intact and relict rock glaciers depicts a broad transition belt in the aspect-elevation space, the amplitude of which varies from as little as 50 m on west facing slopes to a maximum of 500 m on easterly ones. This finding deteriorates the significance of elevation and aspect as topographic proxies for modelling permafrost occurrence, and highlights the importance of using InSAR for informing such models. From a process-oriented standpoint, InSAR information proves fundamental for imaging how this altitudinal transition manifests through changing rates and styles of rock glacier surface deformation. Specifically, we find that as rock glaciers move faster, an increasingly larger proportion of their surface becomes kinematically involved (i.e., percent MA cover), and that this proportion increases with elevation up to the 2600-2800 m, beyond which an inflection occurs and consistent average values are attained. Considering that the inflection falls between the -1°C and -2 °C MAAT - the lower boundary for discontinuous permafrost - and is independent of slope gradient, we conclude that this altitudinal pattern represents a geomorphic signature: the dynamic expression of increasing permafrost distribution (i.e., from sporadic to discontinuous), until optimal thermal conditions are reached. [ABSTRACT FROM AUTHOR]

We evaluate decadal coarse sediment dynamics along the Marecchia River of the Northern Apennines, a fluvial system with a history of gravel mining that led to the incision of a 6-km-long canyon. To this purpose, we subdivided the river into 21 reaches, seen as sediment reservoirs, to examine (1) historical variations in active channel width (1955-2019) in conjunction with (2) change in alluvial sediment storage (2009-2019), by differencing two sequential LiDAR digital elevation models (DEMs) within the active channel footprint. Combined examination of lateral (widening or narrowing) and vertical (aggradation or degradation) channel changes allowed the identification of composite styles of reservoir adjustment, as well as the refinement of geomorphic inference solely based on changes in active channel width. In particular, we find that different styles of decadal adjustment (1) are compatible with supply- and transport-limited conditions, as constrained by degree of confinement, stream channel slope, and active channel width; and (2) indicate different stages of evolution at reservoirs located upstream and downstream of the canyon head (dynamic equilibrium vs. transient response). The persistence of this geomorphic divide is supported over historical time scales by distinctive trends in planform channel changes, suggesting that sedimentary signal propagation downstream becomes abruptly interrupted at the canyon head. Over this 10-year natural experiment, the spatial pattern of erosion along the canyon exemplifies a striking case of transient response to anthropogenic forcing, where decadal topographic change, modulated by varying styles of hillslope-channel coupling, declines nonlinearly downstream. Depth of incision along the canyon increases progressively upstream, suggesting that the canyon head has been evolving toward a more unstable configuration with no significant change in sediment supply. This tendency, which points to a possible runaway style of development as bedload wearing on weak pelitic side walls continues, may hold basic implications for our understanding of channel incision into bedrock and strath terrace formation. [ABSTRACT FROM AUTHOR]