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An overall acceleration of rock glacier displacement rates in the Alps has been observed in recent decades, with several cases of destabilization leading to potential geomorphological hazards. This behaviour has been attributed to the rising permafrost temperature, induced by atmospheric warming and regulated by thermo‐hydrological processes. Landforms derived from the interaction of glacier remnants and permafrost are widespread in mountain areas, but are less studied and monitored than talus rock glaciers. This work presents a comparative study of a talus rock glacier and a glacial‐permafrost composite landform (GPCL) in the Eastern Italian Alps. The two landforms are only 10 km apart, but have rather different elevation ranges and main slope aspects. The kinematics and ground thermal conditions were monitored from 2001 to 2015 along with geomorphological surveys, analyses of historical maps and remote sensing data. The dynamic behaviour of the rock glacier was similar to the majority of monitored rock glaciers in the Alps, with an acceleration after 2008 and a velocity peak in 2015. In contrast, the GPCL had a nearly unchanged displacement rate during the observation period. Statistical analyses of kinematic vs. nivo‐meteorological variables revealed a dynamic decoupling of the two landforms after 2008 that corresponds with increased winter snow accumulation. Although the kinematics of both landforms respond to ground surface temperature variations, the collected evidence suggests a different reaction of ground surface temperature to variations in the precipitation regime. This different reaction is likely due to local topo‐climatic conditions that affect snow redistribution by wind. The different reactions of the two systems to the same climatic forcing is likely a legacy of their different origins. GPCL dynamics result from interaction of permafrost and residual glacial dynamics that are associated with possible peculiarities in the internal/basal meltwater circulation, whose future response is uncertain and requires improved understanding. © 2019 John Wiley & Sons, Ltd. © 2019 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The spatial and temporal characterization of geochemical tracers over Alpine glacierized catchments is particularly difficult, but fundamental to quantify groundwater, glacier melt, and rain water contribution to stream runoff. In this study, we analysed the spatial and temporal variability of δ2H and electrical conductivity (EC) in various water sources during three ablation seasons in an 8.4‐km2 glacierized catchment in the Italian Alps, in relation to snow cover and hydro‐meteorological conditions. Variations in the daily streamflow range due to melt‐induced runoff events were controlled by maximum daily air temperature and snow covered area in the catchment. Maximum daily streamflow decreased with increasing snow cover, and a threshold relation was found between maximum daily temperature and daily streamflow range. During melt‐induced runoff events, stream water EC decreased due to the contribution of glacier melt water to stream runoff. In this catchment, EC could be used to distinguish the contribution of subglacial flow (identified as an end member, enriched in EC) from glacier melt water to stream runoff, whereas spring water in the study area could not be considered as an end member. The isotopic composition of snow, glacier ice, and melt water was not significantly correlated with the sampling point elevation, and the spatial variability was more likely affected by postdepositional processes. The high spatial and temporal variability in the tracer signature of the end members (subglacial flow, rain water, glacier melt water, and residual winter snow), together with small daily variability in stream water δ2H dynamics, are problematic for the quantification of the contribution of the identified end members to stream runoff, and call for further research, possibly integrated with other natural or artificial tracers. [ABSTRACT FROM AUTHOR]

In this work, we present the geological map of the San Pellegrino pass, inserted in the spectacular scenario of the Dolomiti region (Southern Alps, Italy), at a scale of 1:10.000 and accompanied by geological cross-sections. The detailed distinction of lithological thin units allowed to achieve a consistent interpretation of the local structural setting by drawing brittle and ductile Alpine tectonic deformations. The differential deformation and structural styles within the geological map are the result of the different rheological nature of volcanic and sedimentary rocks, as well as of the superimposition of compressional Alpine tectonics over Permo-Mesozoic extensional tectonic phases, and consequent reactivation of inherited structures. [ABSTRACT FROM AUTHOR]

A pronounced climate reorganization characterized the Lateglacial-Holocene transition in the Northern Hemisphere. Glaciers in the Alps reacted to the last climate deterioration at the end of the Late Pleistocene leaving landscape features suitable for reconstructing Lateglacial and early Holocene history. In this context, the Upper Peio Valley in the Ortles-Cevedale Group (Rhaetian Alps, Italy) has well-preserved moraines of La Mare Glacier and Careser Glacier, which we used to reconstruct the glaciers' behaviour and to investigate the Lateglacial-Holocene transition. Detailed glacier reconstructions combined with 11 new 10Be exposure ages allow dating of the response of these glaciers to the Younger Dryas ( YD) cold event. La Mare and Careser glaciers reacted to the YD with a double response, building two clear moraine sets. Data from La Mare Glacier indicate the first advance occurred prior to 12.3±0.7 ka (before 10.0±0.7 ka at Careser Glacier). Both glaciers then re-advanced before 11.2±0.8 ka as dated at La Mare Glacier. This phase can be interpreted as the Egesen stadial glaciers' expression of the end of the YD. Morphometric parameters of the reconstructed phases allowed the estimation of areal and volumetric variations of the studied glaciers as well as equilibrium line altitude ( ELA). Δ ELA with respect to the Little Ice Age ( LIA) maximum position are −225 m for La Mare Glacier and −180 m for the Careser Glacier. Although the behaviour of the two glaciers showed coherence during the Egesen stadial and the LIA, they have behaved individually since then. La Mare has lost 60% of its area, while Careser has lost 85% since the latest Pleistocene. We attribute this to the greater proportion of ice at high elevation of the La Mare Glacier, underlining the importance of bed hypsometry in glacier response. [ABSTRACT FROM AUTHOR]

In 2011 four ice cores were extracted from the summit of Alto dell'Ortles (3859 m), the highest glacier of South Tyrol in the Italian Alps. This drilling site is located only 37 km southwest from where the Tyrolean Iceman, ~5.3 kyrs old, was discovered emerging from the ablating ice field of Tisenjoch (3210 m, near the Italian-Austrian border) in 1991. The excellent preservation of this mummy suggested that the Tyrolean Iceman was continuously embedded in prehistoric ice and that additional ancient ice was likely preserved elsewhere in South Tyrol. Dating of the ice cores from Alto dell'Ortles based on 210Pb, tritium, beta activity and 14C determinations, combined with an empirical model (COPRA), provides evidence for a chronologically ordered ice stratigraphy from the modern glacier surface down to the bottom ice layers with an age of ~7 kyrs, which confirms the hypothesis. Our results indicate that the drilling site has continuously been glaciated on frozen bedrock since ~7 kyrs BP. Absence of older ice on the highest glacier of South Tyrol is consistent with the removal of basal ice from bedrock during the Northern Hemisphere Climatic Optimum (6-9 kyrs BP), the warmest interval in the European Alps during the Holocene. Borehole inclinometric measurements of the current glacier flow combined with surface ground penetration radar (GPR) measurements indicate that, due to the sustained atmospheric warming since the 1980s, an acceleration of the glacier Alto dell'Ortles flow has just recently begun. Given the stratigraphic-chronological continuity of the Mt. Ortles cores over millennia, it can be argued that this behaviour has been unprecedented at this location since the Northern Hemisphere Climatic Optimum. [ABSTRACT FROM AUTHOR]

This work presents an analysis of the mass balance series of nine Italian glaciers, which were selected based on the length, continuity and reliability of observations. All glaciers experienced mass loss in the observation period, which is variable for the different glaciers and ranges between 10 and 47 years. The longest series display increasing mass loss rates, which were mainly due to increased ablation during longer and warmer ablation seasons. The mean annual mass balance (Ba) in the decade from 2004 to 2013 ranged from -1788 to -763 mm w.e. yr-1. Low-altitude glaciers with low range of elevation are more out of balance than the higher, larger and steeper glaciers, which maintain residual accumulation areas in their upper reaches. The response of glaciers is mainly controlled by the combination of October-May precipitations and June-September temperatures, but rapid geometric adjustments and atmospheric changes lead to modifications in their response to climatic variations. In particular, a decreasing correlation of Ba with the June-September temperatures and an increasing correlation with October-May precipitations are observed for some glaciers. In addition, the October-May temperatures tend to become significantly correlated with Ba, possibly indicating a decrease in the fraction of solid precipitation, and/or increased ablation, during the accumulation season. Because most of the monitored glaciers have no more accumulation area, their observations series are at risk due to their impending extinction, thus requiring a replacement soon. [ABSTRACT FROM AUTHOR]

Landslide databases are essential tools for risk assessment. In the Italian portion of the South-Eastern Alps these archives are managed by the Veneto Region and by the provinces of Bolzano and Trento, as part of the Italian Inventory of Landslides. About 750 rockfall events recorded in these archives were checked, put together and completed to create a new integrated database. Information on 24 new rockfalls were added from different research sources. Descriptive statistic shows that the most affected slopes with the highest frequency of rockfall are the southern ones. The distribution of rockfalls during the year presents three peaks in March, June and November. The most commonly affected lithologies are massive dolomites, effusive rocks and mica schists. Roads proved to be the most commonly involved feature. The hypsographic curves obtained from the DEMs of the provinces of Belluno, Bolzano and Trento have shown that the different areas potentially affected by periglacial processes experience rockfalls during summer and autumn, thus representing a risk to tourists and hikers. This study is the first attempt to collate and extend the available information in the various rockfall databases in the Eastern Italian Alps, with the aim at creating uniform data collection for the whole Alpine range. [ABSTRACT FROM AUTHOR]

Highlights: [•] We studied relations among vegetation, soil and geomorphology in alpine habitats. [•] We applied the Association Rules Analysis (ARA), a recent developed methodology. [•] ARA is a powerful method to capture environmental heterogeneity. [•] Landscape units based on vegetation–soil–geomorphology associations were defined. [Copyright &y& Elsevier]