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Periglacial processes on Earth are developing in the glacial regions and under the influence of cold climatic conditions. The periglacial landforms formed due to these processes were formed in paleoclimatic conditions and continue to build today. This study aims to compare the mineralogical properties of the soils in non-sorted steps, which are the periglacial landforms of two mountains (Mount Akbaba-3026 m a.s.l., and Ilgaz Mountains-2587 m a.s.l.) in different geographical regions. For this purpose, detailed clay XRD diffractogram scanning electron microscope (SEM) image acquisition and analysis processes were applied. Albite, muscovite, quartz, and clinochlor minerals were determined as primary minerals in the results obtained from the non-sorted steps of Mount Akbaba. The primary mineral in the Ilgaz Mountains is chlorite. As a result, soils formed on similar landforms in local areas may have different mineralogical characteristics due to different ecological environments and different lithological characteristics. The results are thought to provide theoretical supports for the subject literature. [ABSTRACT FROM AUTHOR]

The main aim of this study is to explain periglacial processes on the summits of Mount Honaz (2571 m a.s.l.), define periglacial landforms, and determine the relationships between morphometric features and topographic factors. Mud circles, stony earth circles, non sorted steps, and non sorted stripes were identified on the summits of Mount Honaz. Pearson's correlation coefficient (r) and linear regression analyses were performed by taking metric measurements from 125 periglacial landforms to describe their morphometric features (length, width, height) of periglacial landforms and explain the relationships between them and topographic factors (elevation, slope). To explain the relationships between periglacial landforms and soil properties, soil samples from 11 periglacial landforms were taken and analysed. Periglacial landforms, which continue to develop on the summits of Mount Honaz today, have been evaluated with present climate data. Analysis of soil samples indicates a notable impact of parent material on the genesis of periglacial landforms. The high ratio of organic matter in mud circle and non sorted step landforms and the high lime ratio in stony earth circle landforms prove a strong relationship between the formation mechanisms of landforms and the soil properties. Furthermore, it is consistent with the findings obtained from the analysis that severe periglacial processes and washing and scavenging events are experienced more on the northern slopes. [ABSTRACT FROM AUTHOR]

Understanding the external and internal geodynamical processes shaping the Earth is challenging. Physical, chemical, and biological processes form the ground surface over time. Erosion, weathering, transporting, and sedimentation are the natural processes that shape landscapes. However, the continuous interactions of external geodynamic drivers, such as water, wind, and biota, play vital roles in shaping the Earth's surface. These complex and interconnected processes impact the landscape and environment, making it essential to comprehend them to predict evolution, variability, and changes. This Topical Collection (TC) is a comprehensive set of over 54 articles (to date, it has over 16,500 accesses and 119 citations) focused on Earth's processes and environment in a changing world. It was grounded in paying tribute to the legacy of the outstanding Spanish geomorphologist, geographer, and honorific Professor Augusto Pérez-Alberti, whose thoughtful contributions have significantly advanced the understanding of earth processes, particularly glacial and periglacial processes, sedimentary dynamics, hydromorphology, and coastal geomorphology. Understanding the geodynamics of the processes that shape Earth systems is critical to protecting and preserving ecosystems, landscapes, natural resources, and communities' well-being. [ABSTRACT FROM AUTHOR]

Boulders are ubiquitous on rocky planets and provide valuable information about planetary processes. The abundance, size, and distribution of boulders offer insights into the primary processes that form them and the secondary processes that modify their position and size. However, the roles of varying environmental processes, including cryospheric processes, are poorly known. In this study, we analyze over 20 million boulders in the northern lowlands of Mars (50–70°N) to evaluate their distribution and identify environmental factors that might influence their clustering. We used spatial statistics to quantify the degree of boulder clustering across the northern plains. We found two latitudinal trends: overall decreasing clustering with increasing latitude (50–70°N) and a sub‐trend of increased clustering at higher latitudes (65–70°N). Our findings suggest that boulder distribution patterns are linked to the latitude‐dependent mantle (LDM) and subsurface ice. Boulders exhibit higher spatial clustering at higher latitudes, where the ice is thick and continuously present, and the LDM is more pristine. Lower clustering occurs at lower latitudes or regions where the ice loss is likely during interglacial periods, and the LDM degrades, exposing more boulders of varying sizes. We also discovered an anomalous region where boulder clustering is nearly random, located on the edge of the Alba Mons Patera. This area displays distinct geophysical characteristics compared to the rest of the lowlands. Although these characteristics do not indicate a specific process for the variation of boulder distribution in this study, the data suggest a coupling between cryospheric processes and boulder evolution, warranting further research. Plain Language Summary: Boulders are common on rocky planets and can provide important information about boulder‐forming processes and displacement. We studied over 20 million boulders on the northern plains of Mars to learn more about how they are distributed across the planet and what factors might influence their placement. We found that boulders are more likely clustered in areas with more ice below the surface. We also discovered an area north of Alba Mons where boulders seem to be scattered randomly, and the surface properties are different than elsewhere in the northern plains. This may be due to the repeated deposition and removal of ice in this area, but more research is needed to fully understand these patterns. Key Points: The level of boulder clustering follows latitudinally varying mantle distribution and degradation statesThe topographic, geophysical, and surface characteristics of northern Alba Patera indicate a higher presence of subsurface iceLandscape ages across the Martian northern lowlands may affect variations in boulder distributions [ABSTRACT FROM AUTHOR]

Maritime Antarctica (M.A.) contains the most extensive and diverse lithological exposure compared to the entire continent. This lithological substrate reveals a rich history encompassing lithological, pedogeomorphological, and glaciological aspects of M.A., all influenced by periglacial processes. Although geophysical surveys can detect and provide valuable information to understand Antarctic lithologies and their history, such surveys are scarce on this continent and, in practice, almost non-existent. In this sense, we conducted a pioneering and comprehensive gamma-spectrometric (natural radioactivity) and magnetic susceptibility (κ) survey on various igneous rocks. The main objective was to create ternary gamma-ray and κ maps using machine learning algorithms, terrain attributes, and a nested-leave-one-out cross-validation method. Additionally, we investigated the relationship between the distribution of natural radioactivity and κ to gain insights into pedogeomorphological and periglacial processes and dynamics. For that, we used proximal gamma-spectrometric and κ data in different lithological substrates associated to terrain attributes. The geophysical variables were collected in the field from various lithological substrates, by use field portable equipment. The geophysical variables were collected in the field from various lithological substrates using portable equipment. These variables, combined with relief data and lithology, served as input data for modeling to predict and spatially map the content of radionuclides and κ by random forest algorithm (RF). In addition, we use nested-LOOCV as a form of external validation in a geophysical data with a small number of samples, and the error maps as evaluation of results. The RF algorithm successfully generated detailed maps of gamma-spectrometric and κ variables. The distribution of radionuclides and ferrimagnetic minerals was influenced by morphometric variables. Nested-LOOCV method evaluated algorithm performance accurately with limited samples, generating robust mean maps. The highest thorium levels were observed in elevated, flat, and west beach areas, where detrital materials from periglacial erosion came through fluvioglacial channels. Lithology and pedogeomorphological processes-controlled thorium contents. Steeper areas formed a ring with the highest uranium contents, influenced by lithology and geomorphological-periglacial processes (rock cryoclasty, periglacial erosion, and heterogeneous deposition). Felsic rocks and areas less affected by periglacial erosion had the highest potassium levels, while regions with sulfurization-affected pyritized-andesites near fluvioglacial channels showed the lowest potassium contents. Lithology and pedogeochemical processes governed potassium levels. The κ values showed no distinct distribution pattern. Pyritized-andesite areas had the highest levels due to sulfurization and associated pyrrhotite, promoting iron release. Conversely, Cryosol areas, experiencing freezing and thawing activity, had the lowest κ values due to limited ferrimagnetic mineral formation. Lithology and pedological-periglacial processes in Cryosols played a significant role in controlling κ values. In regions characterized by diverse terrain attributes and abundant active and intense periglacial processes, the spatial distribution of geophysical variables does not reliably reflect the actual lithological composition of the substrate. The complex interplay of various periglacial processes in the area, along with the morphometric features of the landscape, leads to the redistribution, mixing, and homogenization of surface materials, contributing to the inaccuracies in the predicted-spatialized geophysical variables. [ABSTRACT FROM AUTHOR]

We show a long-term erosion monitoring of several geomorphologically active gully systems on Little Ice Age lateral moraines in the European Central–Eastern Alps, covering a total time period from 1953 to 2019 and including several survey periods in order to identify corresponding morphodynamic trends. For the implementation, DEM (digital elevation model) of Differences (DoDs) were calculated, based on multitemporal high-resolution digital elevation models from historical aerial images (generated by structure from motion photogrammetry with multi-view stereo) and light detection and ranging from airborne platforms. Two approaches were implemented to achieve the corresponding objectives. First, by calculating linear regression models using the accumulated sediment yield and the corresponding catchment area (on a log–log scale), the range of the variability in the spatial distribution of erosion values within the sites. Second, we use volume calculations to determine the total and the mean sediment yield (as well as erosion rates) of the entire sites. Subsequently, both the sites and the different time periods of both approaches are compared. Based on the slopes of the calculated regression lines, it can be shown that the highest variability in the sediment yield at the sites occurs in the first time period (mainly 1950s to 1970s). This can be attributed to the fact that within some sites the sediment yield per square metre increases clearly more strongly (regression lines with slopes up to 1.5). In contrast, in the later time periods (1970s to mid-2000s and mid-2000s to 2017/2019), there is generally a decrease in 10 out of 12 cases (regression lines with slopes around 1). However, even at sites with an increase in the variability in the sediment yield over time, the earlier high variabilities are no longer reached. This means that the spatial pattern of erosion in the gully heads changes over time as it becomes more uniform. Furthermore, using sediment volume calculations and corresponding erosion rates, we show a generally decreasing trend in geomorphic activity (amount of sediment yield) between the different time periods in 10 out of 12 sites, while 2 sites show an opposite trend, where morphodynamics increase and remain at the same level. Finally, we summarise the results of long-term changes in the morphodynamics of geomorphologically active areas on lateral moraines by presenting the "sediment activity concept", which, in contrast to theoretical models, is based on actually calculated erosion. The level of geomorphic activity depends strongly on the characteristics of the sites, such as size, slope length, and slope gradient, some of which are associated with deeply incised gullies. It is noticeable that especially areas with influence of dead ice over decades in the lower slope area show high geomorphic activity. Furthermore, we show that system internal factors, as well as the general paraglacial adjustment process, have a greater influence on long-term morphodynamics than changing external weather and climate conditions, which, however, had a slight impact mainly in the last, i.e. most recent, time period (mid-2000s to 2017/2019) and may have led to an increase in erosion at the sites. [ABSTRACT FROM AUTHOR]

Connecting changes in erosion and vegetation is necessary for predicting topographic and ecologic change in thawing permafrost landscapes. Formerly periglacial landscapes serve as potential analogs for understanding modern permafrost landscape change, yet compared to paleoenvironmental records at these sites, less is known about concurrent geomorphic processes, particularly their rates and relationships to climate change. Here, we target sediments preserved in a central Appalachian peat bog to reconstruct sedimentation across the last deglacial warming. We use ground-penetrating radar and geochemistry of cored bog sediments to quantify sedimentation timing, style, and provenance. Using 14C dating of sedimentary and geochemical shifts, we connect depositional changes to global climate and local vegetation change. We show that deglacial warming promoted deep soil disturbances via solifluction at ca. 14 ka. In contrast, relatively wetter conditions from ca. 10–9 ka promoted shallow disturbance of hillslopes via slopewash, which corresponds to a time of vegetation change. Our results highlight climate-modulated erosion depth and processes in periglacial and post-periglacial landscapes. The existence of similar erosion and vegetation records preserved regionally implies these dynamics were pervasive across unglaciated Appalachian highlands, aiding in reconstructing erosion responses to warming at a resolution with implications for predicting high-latitude landscape responses to disturbance. [ABSTRACT FROM AUTHOR]

We present a field-based reconstruction of the geomorphology in the Subtropical Andean mountains of the Limarí basin, semiarid central Chile (30-31° S). Fieldwork campaigns and remote-sensing analysis served for detailed geomorphological mapping at four formerly glaciated valleys in the heads of the Combarbalá and Río Hurtado sub-basins. We identify a mosaic of glacial, periglacial, and paraglacial landforms. Glacial landforms include a massive dead-ice moraine complex, with thermokarst and debris-filled fractures suggesting former ice-cored moraine degradation. This landform is superimposed by transversal and arcuate ridges suggesting active-ice processes. Periglacial landforms such as rock glaciers, gelifluction, and protalus lobes occur in cirques and U-shaped valleys, but also on moraine deposits. Paraglacial processes are indicated by talus accumulation in those formerly glaciated slopes. The geomorphological imprint is evidence for the interaction and succession between glacial, periglacial, and paraglacial dynamics from the Late Pleistocene to the present. [ABSTRACT FROM AUTHOR]

We present a 1:15,000 geomorphological map of the Maladeta massif in the Central Pyrenees. Our methodology includes fieldwork, the analysis of aerial photographs from 1956 to 2015, and the use of drone flights from 2020 to 2023. The study area consists mainly of granodiorite but also has outcrops of limestone, shales, and quartzites at lower elevations. The landscape of the Maladeta massif is primarily shaped by glacial and periglacial processes, with fluvial, karstic, and hillslope dynamics manifesting in the lower regions. The assessment of moraine thickness has facilitated the determination of maximum glacier thickness during the Little Ice Age (LIA) and has shown that there is no correlation between ice thickness and glacier extent. After the LIA, the massif experienced a continuous glacier retreat. Currently, only 21.4% of the glacier area observed in 1956 remains. [ABSTRACT FROM AUTHOR]

Large, resistant, quartz‐rich boulders deposited on hillslopes and in channels armour the landscape, trap sediment and influence hillslope angle and erodibility. In the Virginia Appalachians, such boulders are a significant component of hillslopes and channels. Establishing the timing of and processes responsible for bedrock fracture and boulder deposition is a critical piece of understanding the landscape as a system. In this study, we use cosmogenic 10Be exposure dating to resolve the timing of boulder deposition at three sites in the Virginia Valley and Ridge province: Gap Mountain, Brush Mountain and Little Stony Creek, and at one site in the Virginia Blue Ridge: Devil's Marbleyard. The correlation between measured boulder exposure ages (101.7 ± 6.9 ka to 10.8 ± 0.8 ka; n = 23) and the Wisconsin Glacial Stage and subsequent Laurentide Ice Sheet (LIS) deglaciation (~115–11.7 ka) suggests a periglacial origin for deposition of large hillslope and channel boulders in the Virginia Appalachians. The lack of boulder exposure ages corresponding to the Last Interglacial Stage or following Wisconsin LIS retreat suggests interglacial non‐deposition and stability. The absence of exposure ages from the penultimate Illinoian or older Quaternary Glacial Stages suggests that periglacial hillslope processes allow the landscape to be resurfaced with large boulders during each return to cold climate conditions. This cyclic resurfacing of hillslopes and channels is an example of how climatic oscillations insert disequilibrium into the landscape cycle and contributes to our appreciation of the timescales over which contemporary climate change may impact boulder dominated landscapes in rapidly warming alpine and arctic environments. [ABSTRACT FROM AUTHOR]

Examining the links and potential feedbacks between tectonics and climate requires understanding the processes and variables controlling erosion. At the orogen scale, tectonics and climate are thought to be linked through the influence of mountain elevation on orographic precipitation and glaciation; the only documented erosional processes capable of balancing rapid rock‐uplift rates are glacial erosion or coupled river incision and landsliding. Our 20 new 10Be derived catchment‐averaged denudation rates from the Western Southern Alps of New Zealand generally range between 0.6 and 9 mm/yr, within the same order of magnitude as fault‐throw rates, exhumation rates, and erosion rates estimated from suspended sediment yields and landslide inventories. Combining our data with previously published 10Be denudation rates, we find that the proportion of catchment area in the 1,500–2,000 m elevation window is the variable that best explains denudation rate variability and the disparity between rock‐uplift rates and denudation rates. This correlation indicates that enhanced erosion likely occurs at 1,500–2,000 m above sea level, where periglacial and paraglacial processes have been proposed to be most active. We find that these temperature‐controlled erosional processes, which are also elevation‐dependent, can play a greater role in modulating erosion during interglacials than precipitation or glaciation. Our data suggest that temperature‐controlled peri‐ and paraglacial erosion could be efficient enough to balance some of the fastest rock‐uplift rates on Earth. Hence, temperature‐controlled erosion could contribute to limiting orogen elevations and modulating the erosion rates dictated by rock‐uplift, playing an essential role in linking tectonics and climate. Plain Language Summary: The shape and evolution of the Earth Surface depend on how the tectonic forces that build up mountains interact with the processes that wear them down through erosion. These erosional processes are often regulated by climate; for example, erosion is commonly more efficient where there are glaciers or in the wetter side of mountain ranges. We present 20 new 10Be concentrations, which are commonly used as a proxy for how fast drainage basins erode, from the Western Southern Alps of New Zealand, one of the fastest‐eroding places on Earth. We find that the rate at which these drainage basins erode is best predicted by the proportion of their drainage area that falls within the 1,500–2,000 m above sea‐level elevation window. This elevation range had previously been suggested to be where rocks are damaged and eroded through freeze‐thaw cycles. It is also the elevation window from which glaciers are currently retreating or have recently retreated, which can intensify erosion. Both freeze‐thaw cycles and glacier retreat depend on elevation and are related to temperature; therefore, we infer that temperature‐controlled erosional processes have likely dominated erosion for the last decades to hundreds of years. Key Points: Twenty new 10Be denudation rates of Western Southern Alps catchments are in the range 0.6–9 mm/yr, and likely >9 mm/yr for two glaciated catchmentsThe proportion of catchment area at 1,500–2,000 masl is the variable that best correlates with observed denudation‐rate variabilityElevation sensitivity of denudation is most likely due to peri‐ and paraglacial processes that modulate the tectonic control on erosion [ABSTRACT FROM AUTHOR]

Air temperatures in Europe in 2022 had been the highest on record for the meteorological summer season [June, July and August (JJA)], with +1.3°C above the 1991–2020 average. We studied the effects of recent warming on permafrost and periglacial conditions at a historical mountain pass in the Eastern Alps (Hochtor, 2,576 m asl, 47.08°N, 12.84°E). We used ground temperature data (2010–2022), repeated electrical resistivity tomography measurements (2019, 2022) and auxiliary data dating back to Roman times. We quantified permafrost conditions, evaluated frost‐related weathering and slope processes and assessed the impact of atmospheric warming on it. Results show that summer ground surface temperatures increased by 2.5°C between 1891–1920 and 1991–2020, whereas frost‐related weathering and periglacial processes decreased. The summers of 2003, 2015, 2019 and 2022 were the four warmest ones in 1887–2022. Hochtor changed in 2010–2022 from an active permafrost site to an inactive one with supra‐permafrost talik. A general three‐layer structure was quantified for all three ERT profiles measured. The middle, 5–10 m thick layer is ice‐poor permafrost detected in 2019, whose existence, although smaller, was confirmed in 2022. Resistivity decreased at the three profiles by 3.9% to 5.2% per year, suggesting permafrost degradation. We interpret the resistivity changes between the summers of 2019 and 2022 as a long‐term signal of permafrost degradation and not as the single effect of the summer heatwave in 2022. As our data show how rapidly permafrost degrades and as we face an even warmer climate for the remaining part of the 21st century, we expect that near‐surface permafrost at the Hochtor site will soon be history. [ABSTRACT FROM AUTHOR]

Frost weathering is a key mechanism of rock failure in periglacial environments and landscape evolution. At high alpine rockwalls, freezing regimes are a combination of diurnal and sustained seasonal freeze-thaw regimes and both influence frost cracking processes. Recent studies have tested the effectiveness of freeze-thaw cycles by measuring weathering proxies for frost damage in low-strength and grain-supported pore space rocks, but detecting frost damage in low-porosity and crackdominated alpine rocks is challenging due to small changes in these proxies that are close to the detection limit. Consequently, the assessment of frost weathering efficacy in alpine rocks may be flawed. In order to fully determine the effectiveness of both freezing regimes, freeze-thaw cycles and sustained freezing were simulated on low-porosity high-strength Dachstein limestone under temperature and moisture conditions that reflect those found in high alpine rockwalls. Frost-induced rock damage was uniquely quantified by combining X-ray computed micro-tomography (µCT), acoustic emission (AE) monitoring and frost cracking modelling. To differentiate between potential mechanisms of rock damage, thermal- and ice-induced stresses were simulated and compared with AE activity. µCT combined with AE data revealed frost damage on low-porosity alpine rocks with crack growth along pre-existing cracks with magnitudes dependent on the initial crack density. It was observed that diurnal freeze-thaw cycles have a higher frost cracking efficacy on alpine rocks compared to a seasonal sustained freezing regime. On north-facing high alpine rockfaces, the number of freeze-thaw cycles and the duration of sustained freezing conditions vary with elevation and seasonal climate. The experimental results establish a link between frost damage and elevation-dependent rockwall erosion rates, which has implications for hazard prediction in mountainous areas under a changing climate. [ABSTRACT FROM AUTHOR]

An updated and complete landslide inventory is the starting point for an appropriate hazard assessment. This paper presents an improvement for landslide mapping by integrating data from two well-consolidated techniques: Differential Synthetic Aperture Radar (DInSAR) and Landscape Analysis through the normalised channel steepness index (ksn). The southwestern sector of the Sierra Nevada mountain range (Southern Spain) was selected as the case study. We first propose the double normalised steepness (ksnn) index, derived from the ksn index, to remove the active tectonics signal. The obtained ksnn anomalies (or knickzones) along rivers and the unstable ground areas from the DInSAR analysis rapidly highlighted the slopes of interest. Thus, we provided a new inventory of 28 landslides that implies an increase in the area affected by landslides compared with the previous mapping: 33.5% in the present study vs. 14.5% in the Spanish Land Movements Database. The two main typologies of identified landslides are Deep-Seated Gravitational Slope Deformations (DGSDs) and rockslides, with the prevalence of large DGSDs in Sierra Nevada being first revealed in this work. We also demonstrate that the combination of DInSAR and Landscape Analysis could overcome the limitations of each method for landslide detection. They also supported us in dealing with difficulties in recognising this type of landslides due to their poorly defined boundaries, a homogeneous lithology and the imprint of glacial and periglacial processes. Finally, a preliminary hazard perspective of these landslides was outlined. [ABSTRACT FROM AUTHOR]

Despite being within the intertropical region of the planet, the Mexican territory still has glacier-covered mountains. In recent decades, important advances have been made in studies on glaciology and periglacial environment in Mexico both for current and past conditions. However, in spite of Cofre de Perote volcano (4200 m a.s.l.) being a strategically located mountain, it has not yet been studied in regards to the glacial and periglacial processes; in fact, those dynamics have modified the mountain massifs in the past. To complement the series of studies on glacial history in the high mountain environment of México, this study reconstructs the glacial cover and the periglacial environment of the volcano surface during the final stage of the Late Pleistocene based on climatic retrospective and through the identification of geomorphological features. The findings indicate the existence of a large glacier (ice cap) that covered the northern, western, and southern slopes of the mountain; while in the eastern sector there were two small glaciers, one being of cirque type, and the other of valley type. The current temperature conditions prevent the occurrence of permanent ice bodies; at the same time, it was found that the periglacial blockfields of the slopes is a legacy of the climatic conditions that prevailed at the end of Late Pleistocene. [ABSTRACT FROM AUTHOR]

Thaw slumping is a periglacial process that occurs on slopes in cold environments, where the ground becomes unstable and the surface slides downhill due to saturation with water during thawing. In this study, GaoFen-1 remote sensing and fused multi-source feature data were used to automatically map thaw slumping landforms in the Beilu River Basin of the Qinghai–Tibet Plateau. The bi-directional cascade network structure was used to extract edges at different scales, where an individual layer was supervised by labeled edges at its specific scale, rather than directly applying the same supervision to all convolutional neural network outputs. Additionally, we conducted a 5-year multi-scale feature analysis of small baseline subset interferometric synthetic aperture radar deformation, normalized difference vegetation index, and slope, among other features. Our study analyzed the performance and accuracy of three methods based on edge object supervised learning and three preconfigured neural networks, ResNet101, VGG16, and ResNet152. Through verification using site surveys and multi-data fusion results, we obtained the best ResNet101 model score of intersection over union of 0.85 (overall accuracy of 84.59%).The value of intersection over union of the VGG and ResNet152 are 0.569 and 0.773, respectively. This work provides a new insight for the potential feasibility of applying the designed edge detection method to map diverse thaw slumping landforms in larger areas with high-resolution images. [ABSTRACT FROM AUTHOR]

The consequences of accelerating climatic warming on Arctic landscape evolution are far‐reaching. In Svalbard, glaciers are rapidly retreating after the Little Ice Age, which leads to exposing new coastal landscapes from marine‐terminating glaciers. Precise quantification of these changes was limited until the complete dataset of Svalbard glacier outlines from 1930's was made available. Here, we analyse the new Svalbard glacier change inventory data and demonstrate that glacier retreat led to a major shift from marine‐terminating towards land‐based glaciers in the last century. This retreat also led to the formation of 922.9 km of new coastline since 1930's creating pristine landscapes governed by paraglacial processes and sediment‐rich nearshore fjord environments. Recent palaeogeographical reconstructions suggest that such a mode of coastal evolution was dominant over the extended periods of the Holocene. Transitions from marine‐terminating to land‐based glaciers have significant implications for fjord circulation, biological production, the state of marine ecosystems, biogeochemical cycles between land and seas and the CO2 budget in coastal waters. [ABSTRACT FROM AUTHOR]

Rockwall erosion by rockfall is largely controlled by frost weathering in high alpine environments. As alpine rock types are characterized by crack‐dominated porosity and high rock strength, frost cracking observations from low strength and grain supported pore‐space rocks cannot be transferred. Here, we conducted laboratory experiments on Wetterstein limestone samples with different initial crack density and saturation to test their influence on frost cracking efficacy. We exposed rocks to real‐rockwall freezing conditions and monitored acoustic emissions as a proxy for cracking. To differentiate triggers of observed cracking, we modeled ice pressure and thermal stresses. Our results show initial full saturation is not a singular prerequisite for frost cracking. We also observe higher cracking rates in less‐fractured rock. Finally, we find that the temperature threshold for frost cracking in alpine rocks falls below −7°C. Thus, colder, north‐exposed rock faces in the Alps likely experience more frost cracking than southern‐facing counterparts. Plain Language Summary: Freezing results in the formation of ice that exerts stresses on fracture walls and draws in additional moisture to supply further growth and break down rocks, a process termed frost cracking. Frost cracking drives much erosion and rockfall in alpine environments. Here we test hypotheses from prior work about how frost cracking is impacted by saturation and rock properties. We exposed rock samples of different strength and saturation to identical freezing conditions in laboratory experiments. We monitored rock temperature and acoustic emissions (AE), assuming frost cracking produces the recorded AE hits. We find that initial full saturation is not required for frost cracking, as water transport is enhanced by fractures in alpine rocks. Furthermore, rock with initial higher short‐term strength showed more frost cracking because, we infer, of stiffness properties that make these rocks more brittle compared to lower strength rocks. Frost cracking occurred at a wide range of temperatures below freezing and was highest between −9 and −7°C. We thus conclude that frost cracking is most impacted by temperature and rock short‐term strength. In Alpine environments, this may result in more frost cracking and rockfall on colder north‐facing rockwalls than warmer southern exposures. Key Points: Initial saturation levels do not limit the efficacy of ice segregation in fractured alpine rocksRock initial crack density impacts rock stiffness and thermal properties and thus frost cracking efficacyThe "frost cracking window" temperature range is dependent on rock strength and crack‐controlled porosity in alpine rocks [ABSTRACT FROM AUTHOR]

Peña Ubiña Massif is one of the highest mountain areas in the Cantabrian Mountains (El Fontán sur, 2417 meters a.s.l.). Due to its vertical orography, it retains the moisture carried by the winds, causing abundant fog and rainfall that exceeds 2000 mm on its summits, many of which are in the form of snow. Karstic, fluviotorrential, glacial, periglacial and gravitational processes and landforms have been identified (relict in some cases and active in others). The action of the karst led to the development of erosive landforms such as dolines, nivokarstic sinkholes, chasms and a great diversity of karren. On the other hand, Peña Ubiña Massif presents a well-developed glacial landscape composed by erosive landforms such as glacial troughs, roches moutonnées and glaciokarst depressions (the latter of mixed genesis, karstic first and glacial later); as well as accumulation landforms, especially several generations of lateral, frontal and basal moraines, which allowed the identification of three main glacial stages (Maximum Ice Expansion Stage or MEH; Internal Stage I and II and Altitude Stage I and II), with 20 glaciers which occupied an extension of 5004 hectares during the MEH Stage. For its part, the present-day thermal regime is characterized by an abundance of frosts, but by a reduced number of freeze-thaw days on the soil. These cold conditions favour the development of cryoturbation, frost shattering, solifluction, rapid mass movements such as debris flows and snow avalanches, and an abundance of snow, which tends to remain between 6-8 months above 1800 meters a.s.l. [ABSTRACT FROM AUTHOR]

Archeological and geoscientific research in loess landscapes remains challenging due to erosional discordances and the relocation of sediments by fluvial erosion and slope wash. The Lower Rhine Embayment (LRE) can serve as a blueprint for archeological and paleoenvironmental research in loess landscapes of Central Europe. The accumulation of wind-blown dust; paleosols developed therein; and the archeological artifacts preserved in loess, colluvial or alluvial sediments are evidence of the Pleistocene and Holocene dynamics of the landscape. Geomorphologic processes in different and specific relief positions must be considered different processes that transform and relocate sediments and archeological remains. Besides aeolian accumulation, erosion and deflation have also transformed the landscape of the LRE. These include fluvial slope wash, gully formation, colluviation, and periglacial processes such as solifluction, cryoturbation and the formation of ice wedge pseudomorphs. In addition, other post-depositional processes, including weathering and soil formation, modify the sedimentary record. In light of the landscape evolution from more hilly landscapes to the flat, agriculturally used terrain we see today, we highlight the relevance and importance of different geomorphological and soil processes including their impacts and challenges for archeological and geoscientific studies. Kurzfassung: Archäologische und geowissenschaftliche Forschung ist in Lösslandschaften aufgrund von Erosionsdiskordanzen und der Verlagerung von Sedimenten durch fluviale Erosion bis heute eine Herausforderung. Die Niederrheinische Bucht kann als Blaupause für die archäologische und paläoökologische Forschung in mitteleuropäischen Lösslandschaften dienen. Die Akkumulation von Staub, darin entwickelte Paläoböden sowie archäologische Artefakte, welche im Löss und den korrelaten Sedimenten wie Kolluvien und Auenlehmen erhalten geblieben sind, liefern wichtige Hinweise für die pleistozäne und holozäne Landschaftsdynamik. All diese Indizien können helfen, die Paläoumweltbedingungen früherer Siedlungen zu verstehen. Die verschiedenen geomorphologischen Prozesse und deren spezifische Reliefposition müssen berücksichtigt werden, da Lösssedimente und darin enthaltene archäologische Artefakte durch diese Prozesse umgewandelt und verlagert werden können. Neben der äolischen Akkumulation haben auch Erosion und Deflation die Landschaft der Niederrheinischen Bucht verändert. Dies sind insbesondere fluviale Hangabspülungen, Erosionsgullies , Kolluvien und periglaziale Prozesse wie Solifluktion, Kryoturbation und die Bildung von Eiskeilpseudomorphosen. Darüber hinaus führen Prozesse nach der Ablagerung, einschließlich Verwitterung und Bodenbildung, zu Veränderungen in den Sedimentarchiven. Vor dem Hintergrund der Landschaftsentwicklung von vorwiegend hügeligen Landschaften hin zum flachen, landwirtschaftlich genutzten Gelände, wie wir es heute vorfinden, beleuchten wir die Relevanz und Bedeutung verschiedener geomorphologischer und bodenkundlicher Prozesse sowie deren Auswirkungen und Herausforderungen für archäologische und geowissenschaftliche Untersuchungen und Studien. [ABSTRACT FROM AUTHOR]

The Batagay megaslump, in the Yana Uplands of northern Yakutia, Russia, is the largest known retrogressive thaw slump in the world. The slump exposes a remarkable sequence of Ice Age permafrost deposits that record the interaction of colluvial, eolian and periglacial processes on a hillslope episodically forested during the last 650 ka or more in response to climate variability on glacial–interglacial timescales. Numerous bones, teeth, and occasional carcasses of Pleistocene and Holocene mammals have been recovered from the permafrost. The megaslump developed over the course of several decades in three stages: (1) gullying, (2) thaw slumping, and (3) megaslumping. After disturbance to the taiga vegetation cover in the 1940s–1960s, a hillslope gully formed by the early 1960s. The gully initiated thaw slumping along its central part during the 1980s, with the slump enlarging to megaslump (>20 ha) proportions during the 1990s. By 2019, the area of the slump had reached about 80 ha and its headwall above the slump floor was up to about 55 m high. The main geomorphic processes of slump growth are headwall ablation and thermal erosion, producing a distinctive terrain of icy badlands on the slump floor. Though much of the megaslump is rapidly growing at present, it will probably stabilize eventually as an irregular terrain characterized by sandy ridges and sand‐filled elongate depressions formed by degradation of the badlands. Comparison of the Batagay megaslump with megaslumps from northwest Canada reveals several similarities and differences in terms of their geomorphology, permafrost deposits, and Quaternary history. [ABSTRACT FROM AUTHOR]

Since the end of the Little Ice Age (LIA, ~1830), the accelerated glaciers' shrinkage along mid-latitude high mountain areas promoted a quick readjustment of geomorphological processes with the onset of the paraglacial dynamic, making proglacial areas among the most sensitive Earth's landscapes to ongoing climate change. A potentially useful remote-sensing method for investigating such dynamic areas is the DEM (Digital Elevation Model) of Difference (DoD) technique, which quantifies volumetric changes in a territory between successive topographic surveys. After a detailed geomorphological analysis and comparison with historical maps of the Martello Valley (central Italian Alps), we applied the DoD for reconstructing post-LIA deglaciation dynamics and reported on the surface effects of freshly-onset paraglacial processes. The head of the valley is still glacierized, with three main ice bodies resulting from the huge reduction of a single glacier present at the apogee of the LIA. Aftermath: the glaciers lose 60% of their initial surface area, largely modifying local landforms and expanding the surface of the proglacial areas. The DoD analysis of the 2006–2015 timeframe (based on registered DEM derived from LiDAR—Light Detection and Ranging—data) highlights deep surface elevation changes ranging from +38 ± 4.01 m along the foot of rock walls, where gravitative processes increased their intensity, to −47 ± 4.01 m where the melting of buried ice caused collapses of the proglacial surface. This approach permits estimating the volume of sediments mobilized and reworked by paraglacial processes. Here, in less than 10 years, −23,675 ± 1165 m3 of sediment were removed along the proglacial area and transported down valley, highlighting the dynamicity of proglacial areas. [ABSTRACT FROM AUTHOR]

Permafrost in the Upper Indus Basin (UIB) in Ladakh, India, is a critical water source and is less studied. Identifying permafrost and its characteristics is a crucial knowledge gap in the UIB. Thus, understanding the permafrost active layer dynamics is critical and essential due to its implications on regional hydrology, infrastructure stability, and disaster occurrence. For this purpose, an experimental site is prepared with 11 plots having two near-surface ground temperature loggers each, i.e., 22 in total, in the upper Ganglass catchment, a sub-region of the UIB, Ladakh. The permafrost active layer thickness characteristics and its thaw progression are simulated using the 1-D GEOtop model with forcing from these 22 loggers from 2016 to 2020. The snow days are calculated using the near-surface ground temperature. The simulation results show no permafrost at 4727 m a.s.l. consistently, whereas all the plots above 4900 m a.s.l. show permafrost active layer thickness, in particular, up to 4 m at 4942 m a.s.l. Permafrost characteristics significantly differ between a warmer (colder) year with low (high) snow. The mean surface offset of the catchment ranges between −0.01° and 5.5°C. These findings on permafrost and associated periglacial processes will provide a critical knowledge base for the stability of high-elevation infrastructure, glacial lakes, regional hydrology and climate, particularly for water. [ABSTRACT FROM AUTHOR]

The article presents a new geosite in a small provincial town in central Poland. It contains twelve Scandinavian erratic boulders from the area, deposited by the Pleistocene ice sheet about 130,000 years ago. The geotrail is equipped with three informative boards, a folder, and each boulder has its own identifier. The article also draws attention to petrographic types and types of erratic boulders among the collected boulders. Their basic dimensions, age, and source area are given. Specific features of rock morphology are discussed. Records of sub/inglacial processes, periglacial processes affecting the forefield of the melting ice sheet, and contemporary morphogenetic processes are also analyzed. The recipient/beneficiary of such information can be anyone who is sensitive to the beauty of abiotic nature, feels heir to the geological past of his region, or wants to broaden his horizons with knowledge from the ice age. The recognized and disseminated heritage of abiotic objects in nature through the transfer of expert knowledge has great potential to become an effective generator of sustainable socio-economic development of peripheral tourist areas. The paper presents in detail expert knowledge and specific examples of improving the quality of life with the creation of this geosite. The tool to be used here is geotourism; it deals with the study of geodiversity and the development of elements of abiotic nature to perform tourist functions in accordance with the principles of nature protection. It protects the geological heritage by effectively securing geosites, widely disseminating geological sciences, and promoting their educational and tourist functions. [ABSTRACT FROM AUTHOR]

Abstract Rockwall erosion by rockfall is largely controlled by frost weathering in high alpine environments. As alpine rock types are characterized by crack‐dominated porosity and high rock strength, frost cracking observations from low strength and grain supported pore‐space rocks cannot be transferred. Here, we conducted laboratory experiments on Wetterstein limestone samples with different initial crack density and saturation to test their influence on frost cracking efficacy. We exposed rocks to real‐rockwall freezing conditions and monitored acoustic emissions as a proxy for cracking. To differentiate triggers of observed cracking, we modeled ice pressure and thermal stresses. Our results show initial full saturation is not a singular prerequisite for frost cracking. We also observe higher cracking rates in less‐fractured rock. Finally, we find that the temperature threshold for frost cracking in alpine rocks falls below −7°C. Thus, colder, north‐exposed rock faces in the Alps likely experience more frost cracking than southern‐facing counterparts.

Alluvial fans are found across a range of climates and are built from a combination of fluvial and debris flow processes. Correct identification of process is critical to reconstructing the climate and water histories of alluvial fans on Earth and Mars. Theory and data from subaerial Earth fans are often used to estimate paleoflow discharges and sediment fluxes for martian fans; however, most terrestrial work has been conducted on fans that are in hot, dry climates with runoff sourced from rainfall. This differs from the prevailing interpretation that martian fans were sourced from snowmelt under warming periglacial conditions. To characterize processes and rates of periglacial fan formation, we conducted a field-based study of the Black Mountain alluvial fan in the Aklavik Range, Canada. We observed active fluvial bedload transport as well as several small debris flows that had initiated from ice-filled gullies. Following a runoff event of ~0.005 mm/hr to ~0.2 mm/hr across the fan, we estimated sediment fluxes of ~0.04 m3/hr. Under bankfull conditions, we estimated runoff rates between ~0.01 mm/hr to ~14 mm/hr and corresponding sediment fluxes of ~0.3 m3/hr to ~550 m3/hr. This suggests that moderate flow events, well below the maximum runoff production rates suggested for Mars, are capable of entraining and transporting appreciable amounts of sediment by fluvial processes. However, sedimentological and geomorphological observations suggest that ~67% of the fan was deposited fluvially; the remainder was deposited by mass flows. Our results emphasize the need to take care in interpreting martian sedimentary processes and climate from fan surface morphology alone. [ABSTRACT FROM AUTHOR]

Glacier forelands are among the most rapidly changing landscapes on Earth. Stable ground is rare as geomorphic processes move sediments across large areas of glacier forelands for decades to centuries following glacier retreat. Yet, most ecological studies sample exclusively on stable terrain to fulfill chronosequence criteria, thus missing potential feedbacks between geomorphic disturbances and vegetation colonization. By influencing vegetation and soil development, such vegetation‐geomorphic disturbance feedbacks could be crucial to understand glacier foreland ecosystem development in a changing climate. We surveyed vegetation and environmental properties, including geomorphic disturbance intensities, in 105 plots located on both stable and unstable moraine terrain in two geomorphologically active glacier forelands in New Zealand and Switzerland. Our plot data showed that geomorphic disturbance intensities permanently changed from high/moderate to low/stable when vegetation reached cover values of around 40%. Around this cover value, species with response and effect traits adapted to geomorphic disturbances dominated. This suggests that such species can act as "biogeomorphic" ecosystem engineers that stabilize ground through positive feedback loops. Across floristic regions, biogeomorphic ecosystem engineer traits creating ground stabilization, such as mat growth and association with mycorrhiza, are remarkably similar. Nonmetric multidimensional scaling revealed a linked sequence of decreasing geomorphic disturbance intensities and changing species composition from pioneer to late successional species. We interpret this linked geomorphic disturbance‐vegetation succession sequence as "biogeomorphic succession," a common successional pathway in unstable river and coastal ecosystems across the world. Soil and vegetation development were related to this sequence and only advanced once biogeomorphic ecosystem engineer species covered 40%–45% of a plot, indicating a crucial role of biogeomorphic ecosystem engineer stabilization. Different topoclimatic conditions could explain variance in biogeomorphic succession timescales and ecosystem engineer root traits between the glacier forelands. As glacier foreland ground is widely unstable, we propose to consider glacier forelands as "biogeomorphic ecosystems" in which ecosystem structure and function are shaped by geomorphic disturbances and their feedbacks with adapted plant species, similar to rivers and coasts. [ABSTRACT FROM AUTHOR]

The Norwegian strandflat is a prominent low-relief bedrock surface found near sea level along most of the west coast of Norway. Its origin has been discussed throughout the last 130 years but is yet to be resolved. Some studies suggest that the strandflat represent a tropical weathering front of Mesozoic age that has since been buried and re-exhumed, while others relate its origin to Pleistocene periglacial and glacial processes and/or wave-induced weathering and erosion. Previous interpretations of the strandflat have considered postglacial isostatic uplift, but the impacts of isostatic changes due to glacial erosion and deposition, as well as dynamic surface changes driven by mantle convection, have been largely overlooked. Here we examine how geomorphological-driven isostatic changes and dynamic surface changes have influenced the land-surface elevation along the Norwegian coast during late Pliocene-Quaternary (the last ca. 3 million years). We employ quantitative estimates of glacial erosion and deposition to assess the flexural isostatic response from the resulting load changes. Our analyses show that patterns of geomorphic isostatic adjustments and dynamic surface changes are generally not reflected in the present elevation of the strandflat. Only the loading effect from the deposition of the North Sea Fan can clearly be correlated with the submerged strandflat found near Stad (∼62 °N). Our results imply that if the strandflat formed synchronously along the Norwegian coast as a flat surface at sea level, the strandflat we observe today must have developed after the majority of late Pliocene-Quaternary glacial erosion took place, but prior to the main deposition of the North Sea Fan. This would place strandflat formation within the last few glacial cycles, but before the Last Glacial Maximum (LGM). This inferred pre-LGM age of the strandflat is generally consistent with cosmogenic nuclide exposure ages and observed striations on the strandflat. Finally, we examine ice cover and land-surface changes relative to sea level during the last 80,000 years and find no extended periods favorable for synchronous strandflat formation across all regions along the Norwegian coast. This implies that either the strandflat is diachronous, or that the processes of formation have either been extremely fast under certain conditions or are independent of sea level, for instance related to glacial erosion. • We have mapped the full on- and offshore extent of the Norwegian Strandflat. • We use isostatic surface adjustments to constrain the time of strandflat origin. • The strandflat was likely created within the last few glacial cycles. • The strandflat was likely created prior to deposition of the North Sea Fan. • No optimal conditions for formation have been met after the Last Glacial Maximum. [ABSTRACT FROM AUTHOR]

The effects of deglaciation on the slope stability of glacial valleys have increasing importance in the context of climate change, as they may affect the susceptibility to large-volume landslides and catastrophic cascading geohazards. On December 16th, 2017, a massive rock slide near a retreating glacier evolved into a debris-mud flow that impacted Villa Santa Lucía in the Chilean Patagonia. This event caused 22 fatalities and severe consequences for the town in terms of infrastructure, connectivity, and economic losses. The landslide occurred in a valley of volcanic dominant geology undergoing a recent deglaciation process in a paraglacial environment, and its triggering is attributed to a historical rainfall event. This work presents the three-dimensional numerical modeling and analysis of the massive rock slide event to address the contribution of glacial processes in developing progressive paraglacial failure of the Santa Lucía landslide, with the role of rainwater infiltration as a triggering factor. A thorough geological and geotechnical characterization of the area was performed, including site reconnaissance, sample retrieval, and laboratory tests. The geological configuration was reproduced through 3D numerical modeling of the glacial stages considering the area’s glacial history. The influence of the historical hydrometeorological event as a triggering factor was simulated and addressed to identify the main features related to the development of the failure initiated at the toe of the slope. The results suggest that the mechanism of deglaciation significantly damaged the rock slope, increasing stress concentration, forming critically stressed joints, and acting as critical factors in preparing the conditions for the landslide to occur. The behavior of the geological structures in the slope under glacial retreat suggests a progressive development of the failure, with the infiltrated rainwater effectively inducing a critical condition of the rock slope, as it reached high saturation in a short time, triggering the landslide. The findings provide meaningful information towards a better understanding of the behavior of rock slopes under paraglacial conditions, considering more realistic glacial influence in time, of critical importance for the design of monitoring and detection tools for strategic development and decision management related to areas where severe geohazards might happen, like the collapse of deglaciated mountain areas where glaciers are retreating. [ABSTRACT FROM AUTHOR]

The cold and dry Younger Dryas (YD) stadial (ca. 12.9 to 11.7 ka) generated glacial deposits in the Iberian Mountains, often restricted to high altitudes in cirque areas. Contrary to expectations, we encountered well-developed YD moraines at relatively low altitudes on the northern slopes of the Cadí Massif in the Southeastern Pyrenees, Spain. We applied the 36Cl terrestrial cosmogenic nuclides (TCN) surface exposure dating method on 11 limestone boulders collected from three moraines to assess the glacial geochronology and paleoclimate conditions associated with their formation. We report a small but well-preserved moraine at an unusually high altitude for the Southeastern Pyrenees (between 2160 m and 2120 m above sea level; asl) fed by a small hanging glacier that formed at 23.0 ± 1.5 ka during the global Last Glacial Maximum (LGM). Four kilometres west of the LGM moraine, a ca. 2.5 km long glacier originating from one of the largest cirques of the Cadí Massif deposited a ca. 700 m long moraine preserved between 1760 m and 1600 m. As alluvial and periglacial processes heavily modified this moraine, we cautiously attribute its age to 12.9 ± 1.0 ka. This age represents the onset of the YD period following the Bølling-Allerød warming, widespread in the Pyrenees. On the other hand, another ca. 1.7 km long glacier sourced from the adjacent cirques deposited a pair of well-preserved lateral moraines and a terminal moraine ca. 1150 m long. The samples collected from the moraines yielded tightly clustered boulder ages (average age = 12.1 ± 1.1 ka). Although they developed at relatively low elevations (1830–2100 m) with an Equilibrium Line Altitude (ELA) of 2175 m, which is exceptional for the Southeastern Pyrenees, these moraines were formed during the YD stadial. Our study suggests that despite increased glacier retreat in the Mediterranean region, local relief is crucial in preserving ice masses far below the modern glacial belt with ample snow accumulation. We also used the Parallel Ice Sheet Model (PISM) to reconstruct the paleo-ice extents and paleoclimate regime. We propose two equally possible best-fit scenarios for the maximum ice extent of the YD period. The first foresees a 4 °C temperature decline with today's precipitation values, and the second predicts a 5 °C cooling if precipitation were 20% lower than today. Identifying and dating this unexpected YD glaciation on Cadí Massif provides new insights into understanding the Iberian Peninsula's paleoclimate. [Display omitted] • Using 36Cl cosmogenic exposure dating, we report the Cadí Massif glacial chronology. • A small Last Glacial Maximum moraine formed at an unexpectedly high altitude. • A 1.7 km long Younger Dryas paleoglacier developed at a surprisingly low altitude. • PISM predicts a 4 °C temperature decline in the YD with today's precipitation values. [ABSTRACT FROM AUTHOR]

Rockslides are a major hazard in mountainous regions. In formerly glaciated regions, the disposition mainly arises from oversteepened topography and decreases through time. However, little is known about this decrease and thus about the present-day hazard of huge, potentially catastrophic rockslides. This paper presents a new theoretical concept that combines the decrease in disposition with the power-law distribution of rockslide volumes found in several studies. The concept starts from a given initial set of potential events, which are randomly triggered through time at a probability that depends on event size. The developed theoretical framework is applied to paraglacial rockslides in the European Alps, where available data allow for constraining the parameters reasonably well. The results suggest that the probability of triggering increases roughly with the cube root of the volume. For small rockslides up to 1000 m3, an exponential decrease of the frequency with an e -folding time longer than 65,000 yr is predicted. In turn, the predicted e -folding time is shorter than 2000 yr for volumes of 10 km3, so that the occurrence of such huge rockslides is unlikely at present times. For the largest rockslide possible at present times, a median volume of 0.5 to 1 km3 is predicted. With a volume of 0.27 km3, the artificially triggered rockslide that hit the Vaiont reservoir in 1963, is thus not extraordinarily large. Concerning its frequency of occurrence, however, it can be considered a 700 to 1200-year event. [ABSTRACT FROM AUTHOR]

In this study, the differences in soil properties formed on various periglacial landforms located on slope land and high elevation so, this case create main problem against to soil erosion. The main aims of the study are to determine the physico-chemical properties and some soil erosion sensitivity parameters of the soils formed on the different periglacial landforms of Mount Cin and to predict those soil erosion sensitivity factor using artificial neural network (ANN). It was detected three different periglacial landforms on the Mount Cin. Stony earth circles spread over Cin Hill which is on the summit plain of Mount Cin, while non-sorted steps are located on the northern slopes of Cin Hill and Topkaya Hill. In addition, mud circle landforms spread to the south of Karaçakrak Hill. 25 soil samples were taken from the periglacial landforms in the study area. Afterwards, the physico-chemical properties of the samples were analysed in the laboratory. According to soil analysis from various periglacial landforms, the dominant soil texture is sandy loam: clay ranges from 5.61 to 16.79%, and sand from 48.61 to 76.72%. Also, the average soil erosion sensitivity factors, namely structure stability index (SSI), dispersion rate (DR), and crust formation (CF), were calculated at 29.65, 28.36, and 40.72%, respectively. Moreover, ANN is a model that can operate directly like the human brain. ANN uses the data of the current problem to make predictions. According to regression results of soil erosion sensitivity factors using ANN, the highest prediction rate was obtained for SSI (78%) and the lowest for DR (57%). [ABSTRACT FROM AUTHOR]

• The newly developed ESR thermochronometry method of quartz was used. • New insights into the Quaternary landscape evolution of the Japanese Alps. • First experimental data for a local relief reduction based on a negative AER. The impact of climate on mountain relief is often questioned, mainly due to the difficulties of measuring surface processes at the timescale of glacial-interglacial cycles. An appropriate setting for studying mountain erosion in response to Quaternary climate change is found in the Tateyama mountains in the Hida mountain range (northern Japanese Alps) due to distinct geomorphological features. The Japanese Alps uplifted within the past ∼1–3 Myr and experienced multiple glaciations during the late Quaternary. We use ultra-low temperature thermochronometers based on the luminescence of feldspar minerals from 19 rock samples and the electron spin resonance (ESR) of quartz minerals from 8 rock samples, in combination with inverse modelling to derive rock cooling rates and exhumation rate histories at 104–106 year timescales from three transects in the Tateyama region. While luminescence signals have already reached their upper dating limit, ESR signals (Al and Ti centres) yielded ESR ages of ∼0.3–1.1 Ma, implying surface processes active in the Pleistocene. Based on a negative age-elevation relationship, local relief reduction at a cirque-basin scale is identified over the past 1 Myr, whereas a positive age distribution with elevation for samples close to the mountain top does not follow this trend. Inverse modelling reveals rock cooling rates on the order of 20–70 °C/Myr, with slightly faster cooling for cirque-floor samples, which equate with erosion rates of 0.5–1 mm/yr that exceed rates from periglacial and slope processes in the same locality. Thus, our data suggest that Quaternary climate change coupled with distinct surface processes modified the slopes of the Tateyama mountains leading to a localised decrease in relief within an individual cirque basin over the second half of the Quaternary. [ABSTRACT FROM AUTHOR]

Polygonal terrain on Mars can form via thermal contraction and subsequent fracturing of the permafrost layer and covers much of the surface poleward of ∼60°. In similar terrains on Earth, seasonal freeze-thaw processes create a range of diverse landforms, including several in which clasts on the surface congregate into sorted circles and polygons. In the Martian northern lowlands, several investigations into boulder patterns have come to differing conclusions on whether analogous organization of clasts is present on Mars, whether there is an association between boulders and polygonal fracture margins, and what periglacial process may cause such organization in the modern environment that does not support seasonal melt. To address this discrepancy, we identify and measure boulders in the Martian northern lowlands with the Martian Boulder Automatic Recognition System (MBARS) and assess boulder spatial patterns to determine if boulders are organized into the margins of underlying fracture polygons. Sixty (60) Images from the High-Resolution Imaging Science Experiment (HiRISE) camera aboard the Mars Reconnaissance Orbiter (MRO) with priorly identified and measured polygons make up our survey, in which MBARS characterized 20 million boulders. We find that boulder patterns are not random across the northern lowlands and tend to be clustered with varying intensity. However, analysis of boulder pairwise distances shows that boulders are not generally organized into the 5–10 m polygonal patterns expected from an alignment of boulders to fracture margins. The lack of widespread polygonal organization of boulders indicates that processes responsible for the modern fracture polygons cannot organize meter-scale boulders towards their margins. This greatly reduces the likelihood of any terrestrial-like freeze-thaw organization occurring since the formation of the modern polygonal terrain in the Martian northern lowlands. Isolated instances of boulder patterns consistent with polygonal organization are found at the northern end of our survey. These instances could indicate a restriction of boulder-organizing processes only to the near-polar terrains but are better explained as selective preservation of paleo-organization. We have abundant evidence that the near-polar terrains on Mars have water ice buried at or very near the surface, much like on Earth. As this ice-rich surface cools in the winter, regularly spaced, roughly hexagonal cracks appear forming so-called "polygonal terrain". In similar permafrost-dominated terrains on Earth, the presence of liquid water near the surface can cause rocks on the surface to be pushed outward during freezing. This eventually leads to the formation of stone circles or stone piles outlining the polygons, often forming large networks of sorted polygons. Using high-resolution images of Mars, we can see boulders as small as 1 m across, and it has been suggested that these boulders might also be organized into the edges of polygons on Mars. This raised the question: did these patterns form through Earth-like, wet processes? Or is there a way to make these patterns without liquid water? To answer this question, we surveyed sixty (60) images of Mars and used the Martian Boulder Automatic Recognition System (MBARS) to identify and measure the boulders in each image, totaling 20 million boulders. We determined that the boulders are not organized into a polygonal pattern, except in a few rare cases. Because the boulders are not organized, it is unlikely that any Earth-like wet processes or an unknown dry process is pushing boulders towards the edges of the fracture polygons. In the few places we do see this organization, it might be a pattern formed sometime in Mars' past when liquid water could exist at or near the surface. • Determine whether boulders are organized into polygonal pattern as seen on Earth. • Uses Martian Boulder Automatic Recognition System (MBARS) to create boulder maps of HiRISE images. • Use Average Nearest Neighbor and spatial statistics to define boulder patterns. • Boulders are not organized into fracture polygon margins in most areas of the martian northern lowlands. • Isolated cases of organization may be remnant from martian paleoclimate. [ABSTRACT FROM AUTHOR]

Schmidt-hammer exposure-age dating (SHD) was applied to ~180 medium- to large-scale solifluction features on the northern edge of Juyflye, Jotunheimen (southern Norway) using an electronic Schmidt-hammer (RockSchmidt) and an improved local SHD age-calibration equation. Age estimates from four different types of solifluction landforms were analysed and compared with those from recalibrated estimates from patterned ground previously investigated on Juvflye. Average SHD-age estimates are c. 9.8 and 9.3 ka for the two dominant morphological types of solifluction features ('type A' boulder tongues and 'type B' stone-banked solifluction lobes) and c. 8.6 ka for sorted stripes and circles. Our results indicate that active formation of all investigated types of solifluction features, sorted stripes, and sorted circles ceased in the Early Holocene, prior to the onset of the regional Holocene Thermal Maximum (HTM) at c. 7.7 ka. Formation of all of these periglacial landforms appears to have commenced shortly after local deglaciation (c. 11.4 ka) in water-saturated till. Alternative origins are rejected, including the possibility of development before the last glaciation, survival beneath cold-based glaciers, and exhumation in the Early Holocene. Cessation of activity is attributed to changing ground conditions affecting active layer processes, particularly reduced soil moisture and pore water pressure. Temporal variations of the altitudinal permafrost limits had little or no impact on the timing of either the Early Holocene climax in activity or subsequent stabilisation. Caution is therefore urged in the utilisation of large-scale solifluction and patterned ground landforms as palaeoclimatic indicators. • Successful application of SHD and improved local age-calibration equation • Climax in periglacial activity during Early Holocene • Stabilisation of solifluction and patterned ground prior to HTM • No relationship between stabilisation and altitudinal permafrost limit • Active layer conditions crucial not presence of underlying permafrost [ABSTRACT FROM AUTHOR]

Disentangling the influence of lithology from the respective roles of climate, topography and tectonic forcing on catchment denudation is often challenging in mountainous landscapes due to the diversity of geomorphic processes in action and of spatial and temporal scales involved. The Dora Baltea catchment (western Italian Alps) is an ideal setting for such investigation, since its large drainage system, extending from the Mont Blanc Massif to the Po Plain, cuts across different major lithotectonic units of the western Alps, whereas this region has experienced relatively homogeneous climatic conditions and glacial history throughout the Quaternary. We acquired new 10 Be-derived catchment-wide denudation rates from 18 river-sand samples collected both along the main Dora Baltea river and at the outlet of its main tributaries. The inferred denudation rates vary between 0.2 and 0.9 mm yr -1 , consistent with previously published values across the European Alps. Spatial variability in denudation rates was statistically compared with topographic, environmental and geological metrics. 10 Be-derived denudation rates do not correlate with modern precipitation and rock geodetic uplift. We find, rather, that catchment topography, in turn conditioned by bedrock structures and erodibility (lithotectonic origin) and glacial overprint, is the main driver of 10 Be-derived denudation patterns. We calculated the highest denudation rate for the Mont Blanc Massif, whose granitoid rocks and long-term tectonic uplift support high elevations, steep slopes and high relief and thus favour intense glacial and periglacial processes and recurring rockfall events. Finally, our results, in agreement with modern sediment budgets, demonstrate that the high sediment input from the Mont Blanc catchment dominates the Dora Baltea sediment flux, explaining the constant low 10 Be concentrations measured along the Dora Baltea course even downstream the multiple junctions with tributary catchments. [ABSTRACT FROM AUTHOR]

Just as glaciers worldwide left a record of past advances and retreats that shifted latitudinally in response to oscillating Quaternary climate changes, so too have cold-climate conditions and permafrost left topographic and sedimentary signatures in former periglacial environments. This review documents widespread occurrence of past permafrost and intense frost action that led to rock fracturing, regolith production, and regolith-mantled slopes in the mid-Atlantic region of the United States during late Pleistocene cold-climate conditions. Strong signatures of thermal contraction cracking and brecciation from frost cracking exist where rocks and sediments are most frost susceptible, as with fissile shales. On sandstone hillslopes, frost weathering produced boulder-rich sediment that episodically flowed slowly down-slope during permafrost thaw, resulting in solifluction lobes and terraces in which colluvium moved cumulatively at least a kilometer. Radiocarbon dating, optically stimulated luminescence age control, and cosmogenic isotope studies constrain some periglacial features to the Last Glacial Maximum but also indicate longer residence times of regolith. Former permafrost and areas of intensive frost cracking extended over much of the mid-Atlantic region of the eastern United States during late Pleistocene cold glacial periods. Cold-climate conditions and permafrost left long-lasting topographic and sedimentary records with limited post-depositional erosion in the formerly periglacial mid-Atlantic region. Prominent relict periglacial landforms include polygon networks and frost wedges that are the result of thermal contraction cracking and brecciated rock formed by segregated ice and frost cracking. Widespread solifluction landforms are a topographic signature of freezing, thawing, and mass movement of mobile regolith produced by frost cracking, and some were active during the Last Glacial Maximum. [ABSTRACT FROM AUTHOR]

A complex landscape lies on an alpine plateau in the high Sierra Nevada, California, and comprises spatially organized physical and ecological features that interact to create a unique ecosystem. At the upslope end a tree-limited ribbon forest of whitebark pines grows on the crest of a short, steep slope, which is the only deformation on the otherwise flat plateau. A long-persistent snowbank forms on the slope in the lee of the ribbon forest; meltwater provides moisture to support a productive wet meadow just below. Below the meadow is a narrow, linear “rampart” comprising large sorted stones, and below this lies a large patterned-ground area of cryogenically sorted circles. The soil domains are densely covered with species-rich vegetation and are abruptly segregated from stone domains. The latter serve as distributed springheads in the otherwise dry patterned-ground terrain. American pikas have colonized the rocky nets of the stone domains and forage plants of the soil circles. The unusual context of this landscape enables pika territories to be more tightly packed than in traditional habitat. We propose a scenario for the Pleistocene origin of this ecosystem and a unique lithologic subsurface barrier that contributes to spring formation during warm intervals.