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Journal articles on the topic 'Periglacial areas'
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Stachoň, Zdeněk, Jan Russnák, Daniel Nývlt, and Filip Hrbáček. "Stabilisation of geodetic points in the surroundings of Johann Gregor Mendel Station, James Ross Island, Antarctica." Czech Polar Reports 4, no. 1 (January 1, 2014): 80–89. http://dx.doi.org/10.5817/cpr2014-1-9.
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The article is focused on issuing of the permanent stabilisation of geodetic points in the periglacial environment. Periglacial environment of ice-free areas of northern James Ross Island is characterised by specific geomorphological processes connected with freezing and thawing and mass movement processes in the superficial part of the ground. Variable intensity of periglacial processes creates main limitations for traditional methods of permanent geodetic point’s stabilisation. This article describes periglacial processes with regards to the traditional stabilisation methods and suggests alternative solutions, which were practically applied and verified on the ice-free area of Ulu Peninsula, northern James Ross Island.
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Berry, T. W., P. R. Fish, S. J. Price, and N. W. Hadlow. "Chapter 10 Periglacial geohazards in the UK." Geological Society, London, Engineering Geology Special Publications 29, no. 1 (2020): 259–89. http://dx.doi.org/10.1144/egsp29.10.
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AbstractAlmost all areas of the UK have been affected by periglaciation during the Quaternary and, as such, relict periglacial geohazards can provide a significant technical and commercial risk for many civil engineering projects. The processes and products associated with periglaciation in the relict periglacial landscape of the UK are described in terms of their nature and distribution, the hazards they pose to engineering projects, and how they might be monitored and mitigated. A periglacial landsystems classification is applied here to show its application to the assessment of ground engineering hazards within upland and lowland periglacial geomorphological terrains. Techniques for the early identification of the susceptibility of a site to periglacial geohazards are discussed. These include the increased availability of high-resolution aerial imagery such as Google Earth, which has proved to be a valuable tool in periglacial geohazard identification when considered in conjunction with the more usual sources of desk study information such as geological, geomorphological and topographical publications. Descriptions of periglacial geohazards and how they might impact engineering works are presented, along with suggestions for possible monitoring and remediation strategies.
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Lautridou, J. P., B. Francou, and K. Hall. "Present-day periglacial processes and landforms in mountain areas." Permafrost and Periglacial Processes 3, no. 2 (April 1992): 93–101. http://dx.doi.org/10.1002/ppp.3430030206.
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Dobiński, Wojciech, Mariusz Grabiec, and Michał Glazer. "Cold–temperate transition surface and permafrost base (CTS-PB) as an environmental axis in glacier–permafrost relationship, based on research carried out on the Storglaciären and its forefield, northern Sweden." Quaternary Research 88, no. 3 (September 14, 2017): 551–69. http://dx.doi.org/10.1017/qua.2017.65.
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AbstractHere, we present empirical ground penetrating radar (GPR) and electroresistivity tomography data (ERT) to verify the cold-temperate transition surface-permafrost base (CTS-PB) axis theoretical model. The data were collected from Storglaciären, in Tarfala, Northern Sweden, and its forefield. The GPR results show a material relation between the glacial ice and the sediments incorporated in the glacier, and a geophysical relation between the “cold ice” and the “temperate ice” layers. Clearly identifying lateral glacier margins is difficult, as periglacial and glacial environments frequently overlap. In this case, we identified areas showing permafrost aggradation already under the glacier, particularly where the CTS is replaced by the PB surface. This structure appears as a result of the influence of a cold climate over both the glacial and periglacial environments. The results show how these surfaces form a specific continuous environmental axis; thus, both glacial and periglacial areas can be treated uniformly as a specific continuum in the geophysical sense. Similarly, other examples previously described also allow identifying a continuation of permafrost from the periglacial environment onto the glacial base. In addition, the ERT results show the presence of double-layered periglacial permafrost, possibly suggesting a past climatic fluctuation in the study area.
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Chauhan, Raju, and Sudeep Thakuri. "Periglacial environment in Nepal Himalaya: Present contexts and future prospects." Nepal Journal of Environmental Science 5 (December 4, 2017): 35–40. http://dx.doi.org/10.3126/njes.v5i0.22713.
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Periglacial environment in the Nepal Himalaya (80°04’ to 88°12’ E longitude and 26°22’ to 30°27’ N latitude) is a research field that has received a little scientific attention although the first reported periglacial research was in 1958. After the first periglacial research, only 22 studies are reported in Nepal (area: 147,181 km2), most of which is carried out by researchers outside the country. Studies mainly focus on periglacial landforms and determining the lower limit of the mountain permafrost. The mean lower limit of permafrost (LLP) and the size of rock glaciers indicate a decreasing trend of the permafrost limit from the eastern (5239 m a.s.l.) to the western part of Nepal (4513 m a.s.l.). The rate of change in the LLP in response to climate change in Nepal Himalaya is 1.3–2.6 m/yr. Model on the scenario of permafrost change based on the IPCC climate scenarios shows that the LLP would rise by 188 m between 2009 and 2039 with the rise in temperature. The periglacial landforms, like vegetated patterned ground (earth hummocks, turf banked terraces), sorted polygons, sorted stripes, solifluction lobes, striated ground, and rock glaciers are reported from the Nepal Himalaya. The spatial and temporal coverage of periglacial research in Nepal Himalaya is very low. The arena of periglacial researches, like permafrost distribution modelling, periglacial hazards, periglacial ecology, relationships between permafrost and rangeland, and implication on mountain livelihood, global warming and periglacial change are the potential areas of research in the coming days.
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Egholm, D. L., J. L. Andersen, M. F. Knudsen, J. D. Jansen, and S. B. Nielsen. "The periglacial engine of mountain erosion – Part 2: Modelling large-scale landscape evolution." Earth Surface Dynamics Discussions 3, no. 2 (April 22, 2015): 327–69. http://dx.doi.org/10.5194/esurfd-3-327-2015.
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Abstract. An increasing number of studies point to a strong periglacial control on bedrock erosion in mountain landscapes. Periglacial processes have also been suggested to control the formation of block-fields on high-elevation, low-relief surfaces (summit flats) found in many alpine landscapes. However, to which degree periglacial processes took part in accelerating global erosion rates in response to Late Cenozoic cooling still remains as an unanswered question. In this study, we present a landscape evolution model that incorporates two periglacial processes; frost cracking and frost creep, which both depend on the mean annual temperature (MAT) and sediment thickness. The model experiments allow us to time-integrate the contribution of periglacial processes to mountain topography over million-year time scales. It is a robust result of our experiments that periglacial frost activity leads to the formation of smooth summit flats at elevations dominated by cold climatic conditions through time periods of millions of years. Furthermore, a simplistic scaling of temperatures to δ18O values through the late-Cenozoic indicates that many of the highest summit flats in mid- to high-latitude mountain ranges can have formed prior to the Quaternary. The model experiments also suggest that cooling in the Quaternary accelerated periglacial erosion by expanding the areas affected by periglacial erosion significantly. A computational experiment combining glacial and periglacial erosion furthermore suggests that landscape modifications associated with glacial activity may increase the long-term average efficiency of the frost-related processes.
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Hamelin, Louis-Edmond, and Peter Clibbon. "Vocabulaire périglaciaire bilingue." Cahiers de géographie du Québec 6, no. 12 (April 12, 2005): 201–26. http://dx.doi.org/10.7202/020381ar.
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A considerable lack of agreement exists, particularly between French and English-speaking geomorphologists, on the precise use of many periglacial terms, and up to the presenty there bas been little correlation of the periglacial terminology of these two languages. Accordingly, the authors have prepared a bilingual glossary of 900 periglacial terms in an attempt to eliminate some of this confusion. Many of the problems encountered in the preparation of this glossary result from different conceptions of the terms « periglacial » and « périglaciaire ». Periglacial studies are generally considered to involve analyses of permanently frozen ground, patterned ground and frost-shattering, whereas the term « périglaciaire »refers to the systematic study of all « cold »processes (except those associated with glacier ice) and their resultant phenomena. The term thus includes, amongst other things, gelifraction, gelifluction, geliturbation, fluvioperiglacial action, effect of sea, lake, river and ground ice, windwork in areas of cold climate, action of snow, and chemical erosion by meltwater.
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Buček, Antonín, Jaromír Kolejka, and Robert Kostka. "Selected landscape forming-processes in the volcanic Putorana Plateau (Taymir, Siberia)." Geografie 101, no. 3 (1996): 232–46. http://dx.doi.org/10.37040/geografie1996101030232.
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The development and products of the natural processes present in the hard rock and weak rock areas of the volcanic Putorana Plateau were studied. Intensive frost weathering causes the degradation of glacial land forms and the formation of periglacial forms. A progressive permafrost degradation occurs on valley bottoms, accompanied by alas lake origin, peat mound creation, pingo degradation and periglacial soil development.
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Uxa, Tomáš, Marek Křížek, and Filip Hrbáček. "PERICLIMv1.0: a model deriving palaeo-air temperatures from thaw depth in past permafrost regions." Geoscientific Model Development 14, no. 4 (April 7, 2021): 1865–84. http://dx.doi.org/10.5194/gmd-14-1865-2021.
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Abstract. Periglacial features, such as various kinds of patterned ground, cryoturbations, frost wedges, solifluction structures, and blockfields, are among the most common relics of cold climate periods, which repetitively occurred throughout the Quaternary. As such, they are widespread archives of past environmental conditions. Climate controls on the development of most periglacial features, however, remain poorly known, and thus empirical palaeo-climate reconstructions based on them have limited validity. This study presents and evaluates a simple new inverse modelling scheme called PERICLIMv1.0 (PERIglacial CLIMate) that derives palaeo-air temperature characteristics related to the palaeo-active-layer thickness, which can be recognized using many relict periglacial features found in past permafrost regions. The evaluation against modern temperature records showed that the model reproduces air temperature characteristics with average errors ≤1.3 ∘C. The past mean annual air temperature modelled experimentally for two sites in the Czech Republic hosting relict cryoturbation structures was between -7.0±1.9 and -3.2±1.5 ∘C, which is well in line with earlier reconstructions utilizing various palaeo-archives. These initial results are promising and suggest that the model could become a useful tool for reconstructing Quaternary palaeo-environments across vast areas of mid-latitudes and low latitudes where relict periglacial assemblages frequently occur, but their full potential remains to be exploited.
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Terhorst, B. "Periglacial cover beds and soils in landslide areas of SW-Germany." CATENA 71, no. 3 (December 2007): 467–76. http://dx.doi.org/10.1016/j.catena.2007.03.021.
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López-Martínez, J., T. Schmid, E. Serrano, S. Mink, A. Nieto, and S. Guillaso. "Geomorphology and landforms distribution in selected ice-free areas in the South Shetland Islands, Antarctic Northern Peninsula region." Cuadernos de Investigación Geográfica 42, no. 2 (September 13, 2016): 435. http://dx.doi.org/10.18172/cig.2965.
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Ice-free areas cover a small percentage of the land in the South Shetland Islands. However, they are significant as they contain ecosystems highly sensitive to environmental changes and are located within a region affected by global warming. These areas are dominated by periglacial, glacial, fluvial, and coastal processes and landforms, where permafrost is often present. Soil development is observed although vegetation cover is sparse and closely related to the geomorphology. The mapping and monitoring of ice-free areas is important as they are highly sensitive to climate change. The objective of this study was to characterize and map surface landforms in ice-free areas using traditional mapping methods as well as advanced remote sensing techniques. Geomorphological and topographical maps were initially obtained through field measurements and observations, and complemented with existing aerial photography at scales between 1:2000 and 1:25000. Thereafter, satellite-borne data became available and were included in the methodology to further determine the distribution of the landforms. In the Antarctic environment, Synthetic Aperture Radar (SAR) provides the most reliable images as data can be obtained in any weather conditions as well as during the day and night. Fully polarimetric SAR RADARSAT-2 were used to determine seven different terrain classes representing surface landforms in ice-free areas around Maxwell Bay (King George Island). The SAR remote sensing techniques were successfully applied to identify different periglacial, fluvial, glacial, coastal, as well as lithological landforms. Field data from Fildes Peninsula were used to train a supervised classifier to map further areas around Maxwell Bay. In this case, the ice-free areas around Maxwell Bay clearly show the dominance of periglacial landforms and processes. Therefore, these techniques can be used to compare past and future results and to monitor areas affected by changing environmental factors and increasing human activities.
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Imaizumi, Fumitoshi, Ryoko Nishii, Kenichi Ueno, and Kousei Kurobe. "Forest harvesting impacts on microclimate conditions and sediment transport activities in a humid periglacial environment." Hydrology and Earth System Sciences 23, no. 1 (January 14, 2019): 155–70. http://dx.doi.org/10.5194/hess-23-155-2019.
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Abstract. Sediment transport activities in periglacial environments are controlled by microclimate conditions (i.e., air and ground temperatures, throughfall), which are highly affected by vegetation cover. Thus, there is the possibility that forest harvesting, the most dramatic change to vegetation cover in mountain areas, may severely impact sediment transport activities in periglacial areas (i.e., soil creep, dry ravel). In this study, we investigated changes in sediment transport activities following forest harvesting in steep artificial forests located in a humid periglacial area of the southern Japanese Alps. In the southern Japanese Alps, rainfall is abundant in summer and autumn, and winter air temperatures frequently rise above and fall below 0∘. Our monitoring by time lapse cameras revealed that gravitational transport processes (e.g., frost creep and dry ravel) dominate during the freeze–thaw season, while rainfall-induced processes (surface erosion and soil creep) occur during heavy rainfall seasons. Canopy removal by forest harvesting increased the winter diurnal ground surface temperature range from 2.7 to 15.9 ∘C. Forest harvesting also increased the diurnal range of net radiation and ground temperature, and decreased the duration of snow cover. Such changes in the microclimate conditions altered the type of winter soil creep from frost creep to diurnal needle-ice creep. Winter creep velocity of ground surface sediment in the harvested site (> 2 mm day−1 on the days with frost heave) was significantly higher than that in the non-harvested site (generally < 1 mm day−1). Meanwhile, sediment flux on the hillslopes, as observed by sediment traps, decreased in the harvested site. Branches of harvested trees left on the hillslopes captured sediment moving downslope. In addition, the growth of understories after harvesting possibly reduced surface erosion. Consequently, removal of the forest canopy by forest harvesting directly impacts the microclimate conditions (i.e., diurnal range of ground temperature and net radiation, duration of snow cover) and increases frequency and velocity of periglacial soil creep, while sediment flux on hillslopes is decreased by branches left on the hillslopes and recovery of understories. The impact of forest harvesting on sediment transport activity is seasonally variable in humid periglacial areas, because microclimate conditions relevant to both freeze–thaw processes and precipitation-induced processes control sediment transport.
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Lehmkuhl, Frank. "Modern and past periglacial features in Central Asia and their implication for paleoclimate reconstructions." Progress in Physical Geography: Earth and Environment 40, no. 3 (December 9, 2015): 369–91. http://dx.doi.org/10.1177/0309133315615778.
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In the continental areas of Central and High Asia, periglacial landform assemblages, sediment structures and processes are mainly influenced and determined by of soil humidity during freeze–thaw cycles. These cryogenic processes result in periglacial landforms such as solifluction, earth hummocks or patterned ground. The distribution of rock glaciers as clear indicators of permafrost is additionally determined by rock fall or moraine debris composed of large boulders (e.g. of granite). Periglacial features were used to reconstruct past climatic conditions, e.g. relict involutions and ice-wedge casts provide evidence for the distribution of former permafrost, say, for the Last Glacial Maximum (LGM). Past temperatures, e.g. mean annual air temperatures, can be estimated from these periglacial features and can be compared with other proxy data, such as glacier fluctuations. Examples from late Holocene solifluction activity in the Altai, Khangai and north-eastern Tibetan Plateau show a different intensity of solifluction processes during the late Holocene and Little Ice Age due to a decrease in temperature and higher soil humidity. The distribution of past permafrost in some regions is still a matter of debate because of different interpretations of sediment structures: sometimes features described as ice-wedge casts may be caused by roots or desiccation cracks due to drying of clay rich sediments. Seismically deformed unconsolidated deposits (seismites) can also be misinterpreted as periglacial involutions. The lack of certain landform assemblages and sediment structures does not necessarily mean that the area had no permafrost. Moisture conditions can also determine the periglacial landform generation to a large degree. They can be ordered in Central Asia as follows (from highest moisture availability to lowest): solifluction; rock glacier; permafrost involutions; ice-wedge casts; sand-wedge casts.
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Andersen, J. L., D. L. Egholm, M. F. Knudsen, J. D. Jansen, and S. B. Nielsen. "The periglacial engine of mountain erosion – Part 1: Rates of frost cracking and frost creep." Earth Surface Dynamics 3, no. 4 (October 6, 2015): 447–62. http://dx.doi.org/10.5194/esurf-3-447-2015.
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Abstract. With accelerating climate cooling in the late Cenozoic, glacial and periglacial erosion became more widespread on the surface of the Earth. The resultant shift in erosion patterns significantly changed the large-scale morphology of many mountain ranges worldwide. Whereas the glacial fingerprint is easily distinguished by its characteristic fjords and U-shaped valleys, the periglacial fingerprint is more subtle but potentially prevails in some mid- to high-latitude landscapes. Previous models have advocated a frost-driven control on debris production at steep headwalls and glacial valley sides. Here we investigate the important role that periglacial processes also play in less steep parts of mountain landscapes. Understanding the influences of frost-driven processes in low-relief areas requires a focus on the consequences of an accreting soil mantle, which characterises such surfaces. We present a new model that quantifies two key physical processes: frost cracking and frost creep, as a function of both temperature and sediment thickness. Our results yield new insights into how climate and sediment transport properties combine to scale the intensity of periglacial processes. The thickness of the soil mantle strongly modulates the relation between climate and the intensity of mechanical weathering and sediment flux. Our results also point to an offset between the conditions that promote frost cracking and those that promote frost creep, indicating that a stable climate can provide optimal conditions for only one of those processes at a time. Finally, quantifying these relations also opens up the possibility of including periglacial processes in large-scale, long-term landscape evolution models, as demonstrated in a companion paper.
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Andersen, J. L., D. L. Egholm, M. F. Knudsen, J. D. Jansen, and S. B. Nielsen. "The periglacial engine of mountain erosion – Part 1: Rates of frost cracking and frost creep." Earth Surface Dynamics Discussions 3, no. 2 (April 22, 2015): 285–326. http://dx.doi.org/10.5194/esurfd-3-285-2015.
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Abstract. With accelerating climate cooling in the late Cenozoic, glacial and periglacial erosion became more widespread on the surface of the Earth. The resultant shift in erosion patterns significantly changed the large-scale morphology of many mountain ranges worldwide. Whereas the glacial fingerprint is easily distinguished by its characteristic fjords and U-shaped valleys, the periglacial fingerprint is more subtle but potentially prevailing in some landscape settings. Previous models have advocated a frost-driven control on debris production on steep headwalls and glacial valley sides. Here we investigate the important role that periglacial processes also play in less steep parts of mountain landscapes. Understanding the influences of frost-driven processes in low-relief areas requires a focus on the consequences of an accreting soil-mantle, which characterizes such surfaces. In this paper, we present a new model that quantifies two key physical processes: frost cracking and frost creep, as a function of both temperature and sediment thickness. Our results yield new insights to how climate and sediment transport properties combine to scale the intensity of periglacial processes. The thickness of the soil-mantle strongly modulates the relation between climate and the intensity of mechanical weathering and sediment flux. Our results also point to an offset between the conditions that promote frost cracking and those that promote frost creep, indicating that a stable climate can only provide optimal conditions for one of those processes at a time. Finally, quantifying these relations also opens the possibility of including periglacial processes in large-scale, long-term landscape evolution models, as demonstrated in a companion paper.
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Deeben, J., H. Hiddink, D. J. Huisman, A. Müller, J. Schokker, and J. Wallinga. "Middle Palaeolithic artefact migration due to periglacial processes; a geological investigation into near-surface occurrence of Palaeolithic artefacts (Limburg-Eastern Brabant coversand region, the Netherlands)." Netherlands Journal of Geosciences - Geologie en Mijnbouw 89, no. 1 (July 2010): 35–50. http://dx.doi.org/10.1017/s0016774600000809.
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AbstractThe original distribution pattern of Middle-Palaeolithic artefacts may be affected by tectonic movement, sedimentation and periglacial processes. This is e.g. the case in the coversand area of Limburg and Eastern Brabant (NL), where the occurrence of numerous finds in a SW-NE trending zone across the Roer Valley Graben is considered enigmatic. In order to elucidate the processes affecting the spatial distribution and the chance of recovery of such artefacts, we investigated a site in Nederweert. At this site, several Middle-Palaeolithic artefacts had been recovered earlier from unexpectedly shallow depths. A test pit profile and grain size analyses revealed that the shallow sediments at this site have been affected by intense, multi-phase cryoturbation, which has deformed the sand and loam layers and partially mixed them thoroughly. As a result, optically stimulated luminescence dating of these sediments yielded widely scattered single-aliquot equivalent dose distributions. Using a Finite Mixture Model (FMM), it was estimated that cryoturbation caused mixing of sediments deposited between 12 and 50 ka with sediment grains deposited between 60-150 ka. The latter material is probably the original context of the Middle-Paleolithic artefacts. Apparently, cryoturbation and potentially other periglacial processes have transported artefacts closer to the surface. Based on these results, we suggest that the occurrence of Middle-Palaeolithic artefacts is caused by (1) the tectonically-induced spatial distribution of layers of this age and (2) periglacial processes having caused migration of artefacts towards the surface. Although periglacial processes may facilitate finding Middle Palaeolithic artefacts, they may severely disturb the original context to such an extent that Middle Palaeolithic sites can no longer be identified. The results of this study form a basis for improving the Indicative Map of Archaeological Values that is used to predict the presence of archaeological sites. The insights gained are also relevant to other areas where Middle-Palaeolithic sites are affected by periglacial processes.
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LAGERBÄCK, ROBERT. "Periglacial phenomena in the wooded areas of Northern Sweden - relicts from the Tärendö Interstadial." Boreas 17, no. 4 (January 16, 2008): 487–99. http://dx.doi.org/10.1111/j.1502-3885.1988.tb00563.x.
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Petrone, Johannes, Gustav Sohlenius, Emma Johansson, Tobias Lindborg, Jens-Ove Näslund, Mårten Strömgren, and Lars Brydsten. "Using ground-penetrating radar, topography and classification of vegetation to model the sediment and active layer thickness in a periglacial lake catchment, western Greenland." Earth System Science Data 8, no. 2 (November 23, 2016): 663–77. http://dx.doi.org/10.5194/essd-8-663-2016.
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Abstract. The geometries of a catchment constitute the basis for distributed physically based numerical modeling of different geoscientific disciplines. In this paper results from ground-penetrating radar (GPR) measurements, in terms of a 3-D model of total sediment thickness and active layer thickness in a periglacial catchment in western Greenland, are presented. Using the topography, the thickness and distribution of sediments are calculated. Vegetation classification and GPR measurements are used to scale active layer thickness from local measurements to catchment-scale models. Annual maximum active layer thickness varies from 0.3 m in wetlands to 2.0 m in barren areas and areas of exposed bedrock. Maximum sediment thickness is estimated to be 12.3 m in the major valleys of the catchment. A method to correlate surface vegetation with active layer thickness is also presented. By using relatively simple methods, such as probing and vegetation classification, it is possible to upscale local point measurements to catchment-scale models, in areas where the upper subsurface is relatively homogeneous. The resulting spatial model of active layer thickness can be used in combination with the sediment model as a geometrical input to further studies of subsurface mass transport and hydrological flow paths in the periglacial catchment through numerical modeling. The data set is available for all users via the PANGAEA database, doi:10.1594/PANGAEA.845258.
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Piermattei, L., L. Carturan, F. de Blasi, P. Tarolli, G. Dalla Fontana, A. Vettore, and N. Pfeifer. "Analysis of glacial and periglacial processes using structure from motion." Earth Surface Dynamics Discussions 3, no. 4 (November 30, 2015): 1345–98. http://dx.doi.org/10.5194/esurfd-3-1345-2015.
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Abstract. Close-range photo-based surface reconstruction from the ground is rapidly emerging as an alternative to lidar (light detection and ranging), which today represents the main survey technique in many fields of geoscience. The recent evolution of photogrammetry, incorporating computer vision algorithms such as Structure from Motion (SfM) and dense image matching such as Multi-View Stereo (MVS), allows the reconstruction of dense 3-D point clouds for the photographed object from a sequence of overlapping images taken with a digital consumer camera. The objective of our work was to test the accuracy of the ground-based SfM-MVS approach in calculating the geodetic mass balance of a 2.1 km2 glacier in the Ortles-Cevedale Group, Eastern Italian Alps. In addition, we investigated the feasibility of using the image-based approach for the detection of the surface displacement rate of a neighbouring active rock glacier. Airborne laser scanning (ALS) data were used as benchmarks to estimate the accuracy of the photogrammetric DTMs and the reliability of the method in this specific application. The glacial and periglacial analyses were performed using both range and image-based surveying techniques, and the results were then compared. The results were encouraging because the SfM-MVS approach enables the reconstruction of high-quality DTMs which provided estimates of glacial and periglacial processes similar to those achievable by ALS. Different resolutions and accuracies were obtained for the glacier and the rock glacier, given the different survey geometries, surface characteristics and areal extents. The analysis of the SfM-MVS DTM quality allowed us to highlight the limitations of the adopted expeditious method in the studied alpine terrain and the potential of this method in the multitemporal study of glacial and periglacial areas.
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Felix-Henningsen, Peter. "Field Trip D (27 September 2018): characteristics and development of the Mesozoic–Tertiary weathering mantle and Pleistocene periglacial slope deposits in the Hintertaunus mountainous region." DEUQUA Special Publications 1 (August 20, 2018): 53–77. http://dx.doi.org/10.5194/deuquasp-1-53-2018.
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Abstract. The Devonian slates and sandstones of the Rhenish Massif were subject to deep and intensive weathering under (sub)tropical climate conditions during the Cretaceous, the Paleogene and the Neogene, which caused the development of a weathering mantle (regolith) >100 m thick, consisting of kaolinitic saprolite and paleosols as well as correlated sediments. Especially the tectonic uplift of the Rhenish Massif and climate change during the Neogene and the Pleistocene led to a vast denudation of the weathering mantle. Only in less uplifted areas of the mountainous region did thick remnants of saprolites remain, and they were covered by Neogene sediments as well as Quaternary periglacial slope deposits. As the kaolinitic weathering products serve as raw materials for the clay industry, unique exposures are available in the Hintertaunus which offer impressive insights into the landscape development of the past ∼80 million years: the excursion proceeds from Giessen to Limburg and further south and southwest to the eastern and western Hintertaunus area. At site 1 near the village of Langhecke, characteristics and properties of the fresh, unweathered slates will be demonstrated. Excursion sites 2 and 3 are situated near the village of Eisenbach. In two open-cast clay mines, both a terrestrial and a semi-terrestrial saprolite from silt slate, covered by periglacial layers, are exposed. Properties and genesis will be discussed on the basis of morphological characteristics and mineralogical and geochemical analyses, as well as isovolumetric elemental mass balances. At site 4 a former basalt quarry near the village of Biebrich exposes a Paleogene Plinthosol above saprolite. The autochthonous paleosol was preserved below Upper Oligocene basalt tuff and periglacial layers. Site 5 is situated within a huge pit for mining of Upper Oligocene to Miocene quartz gravel near the village of Wasenbach. A Miocene Plinthosol developed from alluvial sediments on top of the gravel beds and was covered by periglacial slope deposits. At nearly all sites the basal layers of the periglacial cover beds consist of kaolinitic paleosol/saprolite material, which has an important influence on the site properties of the Holocene soils.
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Jones, Nicholas, and Chris Parker. "Water quality in two Icelandic rivers: the influence of impoundment, agriculture, glaciation and permafrost." Hydrology Research 46, no. 3 (May 20, 2014): 429–45. http://dx.doi.org/10.2166/nh.2014.268.
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The water quality of Icelandic rivers is controlled by a number of natural and anthropogenic factors interacting at complex spatial and temporal scales. This article presents the findings of a study into the water quality of two Icelandic rivers; the Blanda and the Skjálfandafljót. The study investigated the impact of three of the factors influencing water quality in these rivers: impoundment for hydro-electric power generation; agricultural land use; and the presence of glacial and periglacial areas. The results indicate that impoundment within a reservoir was responsible for a significant reduction in turbidity and a significant drop in aluminium concentrations as the reservoir acted as a sediment trap and chemical sink. Agricultural land use was found to have no significant effect on the nitrate or phosphate concentrations. Increasing glacial influence was found to be associated with increased turbidity but decreased total dissolved solids. Finally, the presence of permafrost soils in the periglacial highlands of the Blanda was positively associated with aluminium concentrations.
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Musso, Alessandra, Michael E. Ketterer, Konrad Greinwald, Clemens Geitner, and Markus Egli. "Rapid decrease of soil erosion rates with soil formation and vegetation development in periglacial areas." Earth Surface Processes and Landforms 45, no. 12 (July 23, 2020): 2824–39. http://dx.doi.org/10.1002/esp.4932.
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Nyland, Kelsey E., and Frederick E. Nelson. "Long-term nivation rates, Cathedral Massif, northwestern British Columbia." Canadian Journal of Earth Sciences 57, no. 11 (November 2020): 1305–11. http://dx.doi.org/10.1139/cjes-2019-0176.
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Cryoplanation terraces (CTs) are large (3000–800 000 m2) erosional landforms found in upland periglacial environments. Two hypotheses for the formation of CTs are supported in contemporary literature: (1) CT formation is controlled primarily by geologic structure; and (2) CTs are climatically controlled through nivation, a suite of erosional processes associated with late-lying snowbanks. A persistent question in periglacial geomorphology is whether nivation can produce CT-scale landforms. This paper examines the unusual deglaciation history of “Frost Ridge” on the Cathedral Massif, northwestern British Columbia, to estimate long-term denudation attributable to nivation processes active since the last glacial maximum. Frost Ridge forms one flank of an east–west-oriented glacial valley. During deglaciation, marginal drainage created V-shaped erosional notches on both valley walls. Minimization of solar radiation on the steep north-facing wall (Frost Ridge) allowed snowbanks to accumulate and persist in the marginal drainage features and nivation processes to erode the slope. Today, several large nivation hollows (incipient CTs) are present near the summit of Frost Ridge, while the V-shaped marginal drainage features are preserved at lower elevations and on the opposite, south-facing valley wall. A high-resolution survey using an unmanned aerial vehicle (UAV) allowed volumes of marginal drainage and incipient terrace features to be compared. Based on this volumetric comparison, denudation rates are estimated to range from 4.2 to 125.8 mm/kyr, which are comparable with relatively short-term nivation rates reported from Antarctica and mid-latitude alpine periglacial areas.
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Etienne, Samuel. "The role of biological weathering in periglacial areas: a study of weathering rinds in south Iceland." Geomorphology 47, no. 1 (September 2002): 75–86. http://dx.doi.org/10.1016/s0169-555x(02)00142-3.
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Haeberli, Wilfried, and Jean-Pierre Lautridou. "Introduction—international workshop on permafrost and periglacial environments in mountain areas, Interlaken (Switzerland), 16–20 September." Permafrost and Periglacial Processes 3, no. 2 (April 1992): 71–72. http://dx.doi.org/10.1002/ppp.3430030203.
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Poelking, E. L., C. E. R. Schaefer, E. I. Fernandes Filho, A. M. de Andrade, and A. A. Spielmann. "Soil–landform–plant communities relationships of a periglacial landscape at Potter Peninsula, Maritime Antarctica." Solid Earth Discussions 6, no. 2 (August 6, 2014): 2261–92. http://dx.doi.org/10.5194/sed-6-2261-2014.
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Abstract. Integrated studies on the interplay between soils, periglacial geomorphology and plant communities are crucial for the understanding of climate change effects on terrestrial ecosystems of Maritime Antarctica, one of the most sensitive areas to global warming. Knowledge on physical environmental factors that influence plant communities can greatly benefit studies on monitoring climate change in Maritime Antarctica, where new ice-free areas are being constantly exposed, allowing plant growth and organic carbon inputs. The relationship between topography, plant communities and soils was investigated in Potter Peninsula, King George Island, Maritime Antarctica. We mapped the occurrence and distribution of plant communities and identified soil–landform–vegetation relationships. The vegetation map was obtained by classification of a Quickbird image, coupled with detailed landform and characterization of 18 soil profiles. The sub-formations were identified and classified, and we also determined the total elemental composition of lichens, mosses and grasses. Plant communities at Potter Peninsula occupy 23% of the ice-free area, at different landscape positions, showing decreasing diversity and biomass from the coastal zone to inland areas where sub-desert conditions prevail. There is a clear dependency between landform and vegetated soils. Soils with greater moisture or poorly drained, and acid to neutral pH, are favourable for mosses subformations. Saline, organic-matter rich ornithogenic soils of former penguin rookeries have greater biomass and diversity, with mixed associations of mosses and grasses, while stable felseenmeers and flat rocky cryoplanation surfaces are the preferred sites for Usnea and Himantormia lugubris lichens, at the highest surface. Lichens subformations cover the largest vegetated area, showing varying associations with mosses.
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Savidge, Rodney Arthur. "Evidence for early glaciation of southeastern Beringia." Canadian Journal of Earth Sciences 57, no. 2 (February 2020): 199–226. http://dx.doi.org/10.1139/cjes-2019-0048.
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Between the Klondike Plateau and Yukon–Tanana highlands of Yukon and Alaska, respectively, current maps explain glaciated alpine locales and periglacial areas in terms of localized Pliocene–Pleistocene montane ice caps, alpine glaciers, and periglacial changes. However, this region’s plateau topography is populated with long undulating ridges having wide flattened tops; it contrasts with relief of other regions of northwestern North America also affected by ice caps, cryoplanation, and erosion over similar duration during the same epochs. This region has received minimal research and appears to present a new opportunity for resolving outstanding glaciological and stratigraphy issues. The glaciological history is reviewed, placing particular emphasis upon the low-elevation ridges within the “unglaciated” region, suggesting that those ridges are relict arête/cirque remnants. Sites of subalpine glacial grooving and mountaintop planing are also identified, and a conglomeratic red bed containing erratic clasts is described. All indications point to the “unglaciated” region having been glaciated before late Pliocene. Two working hypotheses are proposed: (1) The landscape once supported a range of young mountains that became glaciated then overridden and pared to a plateau by an ice sheet. (2) Following deglaciation, an extended period of paraglacial activity removed most of the former drift and excised new valleys to give the region an unglaciated appearance, which thereafter became modified into its present state by local montane/alpine glaciations, interglacial cryoplanation, periglacial gelifraction, and erosion. In addition to Pliocene–Pleistocene glaciations, a northeastward advancing Miocene ice sheet seems plausible and, on the basis of paleographic considerations and lithology, a Cretaceous glaciation evidently is also not out of the question.
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Poelking, E. L., C. E. R. Schaefer, E. I. Fernandes Filho, A. M. de Andrade, and A. A. Spielmann. "Soil–landform–plant-community relationships of a periglacial landscape on Potter Peninsula, maritime Antarctica." Solid Earth 6, no. 2 (May 27, 2015): 583–94. http://dx.doi.org/10.5194/se-6-583-2015.
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Abstract. Integrated studies on the interplay between soils, periglacial geomorphology and plant communities are crucial for the understanding of climate change effects on terrestrial ecosystems of maritime Antarctica, one of the most sensitive areas to global warming. Knowledge on physical environmental factors that influence plant communities can greatly benefit studies on the monitoring of climate change in maritime Antarctica, where new ice-free areas are being constantly exposed, allowing plant growth and organic carbon inputs. The relationship between topography, plant communities and soils was investigated on Potter Peninsula, King George Island, maritime Antarctica. We mapped the occurrence and distribution of plant communities and identified soil–landform–vegetation relationships. The vegetation map was obtained by classification of a QuickBird image, coupled with detailed landform and characterization of 18 soil profiles. The sub-formations were identified and classified, and we also determined the total elemental composition of lichens, mosses and grasses. Plant communities on Potter Peninsula occupy 23% of the ice-free area, at different landscape positions, showing decreasing diversity and biomass from the coastal zone to inland areas where sub-desert conditions prevail. There is a clear dependency between landform and vegetated soils. Soils that have greater moisture or are poorly drained, and with acid to neutral pH, are favourable for moss sub-formations. Saline, organic-matter-rich ornithogenic soils of former penguin rookeries have greater biomass and diversity, with mixed associations of mosses and grasses, while stable felsenmeers and flat rocky cryoplanation surfaces are the preferred sites for Usnea and Himantormia lugubris lichens at the highest surface. Lichens sub-formations cover the largest vegetated area, showing varying associations with mosses.
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Gruber, F. E., and M. Mergili. "Regional-scale analysis of high-mountain multi-hazard and risk in the Pamir (Tajikistan) with GRASS GIS." Natural Hazards and Earth System Sciences Discussions 1, no. 2 (April 26, 2013): 1689–747. http://dx.doi.org/10.5194/nhessd-1-1689-2013.
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Abstract. We present a model framework for the regional-scale analysis of high-mountain multi-hazard and -risk, implemented with the Open Source software package GRASS GIS. This framework is applied to a 98 300 km2 study area centred in the Pamir (Tajikistan). It includes (i) rock slides, (ii) ice avalanches, (iii) periglacial debris flows, and (iv) lake outburst floods. First, a hazard indication score is assigned to each relevant object (steep rock face, glacier or periglacial slope, lake). This score depends on the susceptibility and on the expected event magnitude. Second, the possible travel distances, impact areas and, consequently, impact hazard indication scores for all types of processes are computed using empirical relationships. These scores are finally superimposed with an exposure score derived from the type of land use, resulting in a raster map of risk indication scores finally discretized at the community level. The analysis results are presented and discussed at different spatial scales. The major outcome of the study, a set of comprehensive regional-scale hazard and risk indication maps, shall represent an objective basis for the prioritization of target communities for further research and risk mitigation measures.
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Smith, C. A. S., C. Tarnocai, and O. L. Hughes. "Pedological Investigations of Pleistocene Glacial Drift Surfaces in the Central Yukon." Géographie physique et Quaternaire 40, no. 1 (December 4, 2007): 29–37. http://dx.doi.org/10.7202/032620ar.
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ABSTRACT Distinct soil morphologies associated with three different ages of Quaternary glacial deposits are characterized and subsequently named. Properties which provide a basis for distinguishing these in the field include solum depth, B horizon colour, clay skin development, coarse fragment weathering and periglacial features. A strong relationship is evident between the clay content at depth and the age of soil. Low values of Na pyrophosphate-extractable Fe and Al confirm the absence of any active podzol-forming processes even within the reddest (5YR, 2.5YR) soil horizons. Wounded Moose paleosols are the preserved soils observed on pre-Reid Glaciation (.2-1.2 Ma) deposits which show strong paleoargillic horizon development with red colours, high clay content, and common periglacial modification. Diversion Creek paleosols are the preserved soils found on Reid (80-120 ka) glacial deposits which show moderate paleoargillic horizon development and resemble the contemporary Gray Luvisols of the mid and southern boreal forest regions of Canada. Stewart soils are the weakly developed Brunisols formed on stable landform surfaces of McConnell (14-30 ka) glacial deposits. The Wounded Moose and Diversion Creek paleosols, while found commonly in local areas, occupy only a small proportion of the regional landscape.
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Gruber, F. E., and M. Mergili. "Regional-scale analysis of high-mountain multi-hazard and risk indicators in the Pamir (Tajikistan) with GRASS GIS." Natural Hazards and Earth System Sciences 13, no. 11 (November 7, 2013): 2779–96. http://dx.doi.org/10.5194/nhess-13-2779-2013.
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Abstract. We present a model framework for the regional-scale analysis of high-mountain multi-hazard and -risk indicators, implemented with the open-source software package GRASS GIS. This framework is applied to a 98 300 km2 study area centred in the Pamir (Tajikistan). It includes (i) rock slides, (ii) ice avalanches, (iii) periglacial debris flows and (iv) lake outburst floods. First, a hazard indicator is assigned to each relevant object (steep rock face, glacier or periglacial slope, lake). This indicator depends on the susceptibility and on the possible event magnitude. Second, the possible travel distances, impact areas and, consequently, impact hazard indicators for all types of processes are computed using empirical relationships. The impact hazard indicators are finally superimposed with an exposure indicator derived from the type of land use, resulting in a raster map of risk indicators finally discretized at the community level. The analysis results are presented and discussed at different spatial scales. The major outcome of the study, a set of comprehensive regional-scale hazard and risk indication maps, shall represent an objective basis for the prioritization of target communities for further research and risk mitigation measures.
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Lehmkuhl, F., and M. Klinge. "Measurements of soil temperatures in the northern Mongolian Altai as indicators for periglacial geomorphodynamic in mountain areas." Zeitschrift für Geomorphologie 44, no. 1 (April 5, 2000): 75–102. http://dx.doi.org/10.1127/zfg/44/2000/75.
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Piermattei, Livia, Luca Carturan, Fabrizio de Blasi, Paolo Tarolli, Giancarlo Dalla Fontana, Antonio Vettore, and Norbert Pfeifer. "Suitability of ground-based SfM–MVS for monitoring glacial and periglacial processes." Earth Surface Dynamics 4, no. 2 (May 20, 2016): 425–43. http://dx.doi.org/10.5194/esurf-4-425-2016.
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Abstract. Photo-based surface reconstruction is rapidly emerging as an alternative survey technique to lidar (light detection and ranging) in many fields of geoscience fostered by the recent development of computer vision algorithms such as structure from motion (SfM) and dense image matching such as multi-view stereo (MVS). The objectives of this work are to test the suitability of the ground-based SfM–MVS approach for calculating the geodetic mass balance of a 2.1 km2 glacier and for detecting the surface displacement of a neighbouring active rock glacier located in the eastern Italian Alps. The photos were acquired in 2013 and 2014 using a digital consumer-grade camera during single-day field surveys. Airborne laser scanning (ALS, otherwise known as airborne lidar) data were used as benchmarks to estimate the accuracy of the photogrammetric digital elevation models (DEMs) and the reliability of the method. The SfM–MVS approach enabled the reconstruction of high-quality DEMs, which provided estimates of glacial and periglacial processes similar to those achievable using ALS. In stable bedrock areas outside the glacier, the mean and the standard deviation of the elevation difference between the SfM–MVS DEM and the ALS DEM was −0.42 ± 1.72 and 0.03 ± 0.74 m in 2013 and 2014, respectively. The overall pattern of elevation loss and gain on the glacier were similar with both methods, ranging between −5.53 and + 3.48 m. In the rock glacier area, the elevation difference between the SfM–MVS DEM and the ALS DEM was 0.02 ± 0.17 m. The SfM–MVS was able to reproduce the patterns and the magnitudes of displacement of the rock glacier observed by the ALS, ranging between 0.00 and 0.48 m per year. The use of natural targets as ground control points, the occurrence of shadowed and low-contrast areas, and in particular the suboptimal camera network geometry imposed by the morphology of the study area were the main factors affecting the accuracy of photogrammetric DEMs negatively. Technical improvements such as using an aerial platform and/or placing artificial targets could significantly improve the results but run the risk of being more demanding in terms of costs and logistics.
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Leibman, M. O., S. M. Arkhipov, D. D. Perednya, A. S. Savvichev, B. G. Vanshtein, and H. W. Hubberten. "Geochemical properties of the water–snow–ice complexes in the area of Shokalsky glacier, Novaya Zemlya, in relation to tabular ground-ice formation." Annals of Glaciology 42 (2005): 249–54. http://dx.doi.org/10.3189/172756405781812952.
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AbstractTabular (massive) ground ice in periglacial areas of the Russian Arctic (Barents and Kara Sea coasts) is considered to be a remnant of past glacial epochs and is thus used as proof of the glacial extent. In this paper, we argue that the origin of these tabular ice bodies, which can be used as archives of specific climatic conditions and periglacial environments, is intra-sedimentary (migration/intrusion). The objective of this study is to establish geochemical benchmarks describing the ice formation from atmospheric moisture and compare them with geochemical data of tabular ground ice. Shokalsky glacier on Novaya Zemlya (NZ), on the east coast of the Barents Sea, was chosen as a possible moisture source for the formation of tabular ground ice at the key section ‘Shpindler’ on Yugorsky peninsula, on the south coast of the Kara Sea. Tabular ice in the Shpindler section was compared to the Shokalsky glacier ice in both isotope/geochemical and structural aspects. In general, the hydrochemical properties of glacier ice at NZ and ground ice from Shpindler are closely correlated, while stable-isotope, microelemental and microbiological properties are substantially different. It was concluded that glacier ice most likely participated in the formation of tabular ground ice, but only as a source of refrozen meltwater.
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Mieszkowski, Radosław, Jan Dzierżek, and Dominik Stańczuk. "Application of geoelectrical profiling in the delineation of shallow periglacial structures on the Drohiczyn Plateau." Studia Quaternaria 31, no. 2 (December 1, 2014): 73–81. http://dx.doi.org/10.2478/squa-2014-0007.
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Abstract The paper describes the results of geoelectrical sounding application for delineation of periglacial structures in Wierzchuca Nagórna within the Drohiczyn Plateau (eastern Poland). The method records the variation of apparent resistivity of deposits along a selected horizontal direction. The survey utilizes a distinct geoelectrical contrast between a glacial till and structures composed of sand that have been recognized earlier in a gravel pit wall. The studies have been conducted in direct hinterland of the gravel pit. Rectangular and concentric arrays were applied in the survey. The results have been presented as graphs and resistance distribution maps. The obtained geological image is not complete, although it shows an oriented course of the largest lineaments and traces of a network with a small mesh size (1.5-2 m). The recognized pattern of structures points to harsh climatic conditions during their formation. General orientation of the structures corresponds to the basic elements of the contemporary landscape in the area (slope, valley axes). Geoelectrical sounding using the rectangular array gave better results than in the concentric array, whereas introduction of brine into the system did not enhance the resolution of the readings. The presented resistance distribution maps with a characteristic rhythm of variations may serve as a benchmark for recognizing periglacial structures in areas without exposures.
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Lukas, Sven. "Morphostratigraphic principles in glacier reconstruction -a perspective from the British Younger Dryas." Progress in Physical Geography: Earth and Environment 30, no. 6 (December 2006): 719–36. http://dx.doi.org/10.1177/0309133306071955.
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Glacier reconstruction enables the calculation of palaeoglaciological and palaeoclimatic variables such as the equilibrium-line altitude and palaeo-precipitation values. Such data are important for our understanding of past atmosphere-cryosphere interactions and as input variables to constrain numerical models effectively. Numerical dating is crucial to constrain the age of glacial events, but, due to absence of dateable material and/or contamination problems, ice masses can frequently be constrained satisfactorily only in a few locations. Thus, extrapolation and interpolation of geomorphological evidence is required to establish the extent of glaciers at a given time for the whole ice mass. Using examples from areas in Britain that were last covered by glaciers during the Younger Dryas, geomorphological approaches are reviewed and potential pitfalls highlighted. A multiproxy morphostratigraphic approach that utilizes clear landsystem contrasts inside and outside dated glacial limits is developed and tested in an area where numerical dates are sparse. Landform assemblages suitable in this respect are the type and frequency of moraines, river terrace sequences, glaciofluvial landforms, raised beaches, the upslope terminations of sediment cover (‘drift limits’), periglacial trimlines and periglacial features such as blockfields, solifluction lobes and thick talus accumulations. It is concluded that, if multiple lines of geomorphological evidence converge, these can be used to confine the extent of past glaciers in a given area and to guide dating programmes.
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Kaiser, Sonja, Mathias Göckede, Karel Castro-Morales, Christian Knoblauch, Altug Ekici, Thomas Kleinen, Sebastian Zubrzycki, Torsten Sachs, Christian Wille, and Christian Beer. "Process-based modelling of the methane balance in periglacial landscapes (JSBACH-methane)." Geoscientific Model Development 10, no. 1 (January 24, 2017): 333–58. http://dx.doi.org/10.5194/gmd-10-333-2017.
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Abstract. A detailed process-based methane module for a global land surface scheme has been developed which is general enough to be applied in permafrost regions as well as wetlands outside permafrost areas. Methane production, oxidation and transport by ebullition, diffusion and plants are represented. In this model, oxygen has been explicitly incorporated into diffusion, transport by plants and two oxidation processes, of which one uses soil oxygen, while the other uses oxygen that is available via roots. Permafrost and wetland soils show special behaviour, such as variable soil pore space due to freezing and thawing or water table depths due to changing soil water content. This has been integrated directly into the methane-related processes. A detailed application at the Samoylov polygonal tundra site, Lena River Delta, Russia, is used for evaluation purposes. The application at Samoylov also shows differences in the importance of the several transport processes and in the methane dynamics under varying soil moisture, ice and temperature conditions during different seasons and on different microsites. These microsites are the elevated moist polygonal rim and the depressed wet polygonal centre. The evaluation shows sufficiently good agreement with field observations despite the fact that the module has not been specifically calibrated to these data. This methane module is designed such that the advanced land surface scheme is able to model recent and future methane fluxes from periglacial landscapes across scales. In addition, the methane contribution to carbon cycle–climate feedback mechanisms can be quantified when running coupled to an atmospheric model.
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Haeberli, Wilfried, Michèle Evin, Geneviève Tenthorey, H. R. Kensen, Martin Hoelzle, Felix Keller, Daniel Vonder Mühll, Stephan Wagner, Manuela Pelfini, and Claudio Smiraglia. "Permafrost research sites in the Alps: Excursions of the international workshop on permafrost and periglacial environments in mountain areas." Permafrost and Periglacial Processes 3, no. 3 (July 1992): 189–202. http://dx.doi.org/10.1002/ppp.3430030304.
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Lee, Jaeyong, and Takashi Oguchi. "Toward high resolution mapping of patterned ground with vegetation in Spitsbergen using a UAV." Abstracts of the ICA 1 (July 15, 2019): 1–2. http://dx.doi.org/10.5194/ica-abs-1-208-2019.
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<p><strong>Abstract.</strong> We focused on technical methods for mapping of periglacial terrain in Spitsbergen, Svalbard. In polar regions, there are permafrost areas with patterned ground formed by physical movement of the surface layer of permafrost, reflecting the characteristics of climate and topography. Also, mosses and lichens covering the topsoil are likely to be related to climate and topography. Since patterned ground is generated slowly over a long period, it is highly sensitive to changes in the polar environment. Vegetation is the main nutrient source for polar animals. Therefore, understanding the status of vegetation is important for monitoring and managing the polar environment in general.</p>
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Чотчаев, Х. О., О. Г. Бурдзиева, and В. Б. Заалишвили. "Influence of geodynamic processes on the geoecological state of high mountain areas." Геология и геофизика Юга России, no. 4() (December 21, 2020): 70–100. http://dx.doi.org/10.46698/vnc.2020.87.26.005.
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Научно обоснованный прогноз геоэкологической эволюции территорий на основе анализа причинно-следственной зависимости эндогенных и экзогенных процессов является актуальной задачей обеспечения безопасности рекреантов и планирования долгосрочного развития высокогорных туристско-рекреационных комплексов. Цель исследований – долгосрочной прогноз геоэкологической эволюции территории на основе факторов геодинамического развития и их признаков в геофизических полях. Для достижения поставленной цели решались следующие задачи: анализ современных представлений о влиянии эндогенных геодинамических процессов на изменения природной среды горных территорий и определение геодинамической концепции геоэкологической зависимости; методологическое обоснование проявлений геофизических полей-индикаторов тектономагматических процессов и выбор методов их исследования, выделение зон активных разломов и неотектонических проявлений. Использованы материалы исследований методами обменных волн землетрясений, гравимагнитометрии, микросейсмического зондирования, электротомографии, преломленных сейсмических волн, геолокации. В качестве результатов исследований делается вывод, что геоэкологические изменения вызваны неотектоникой трещинного типа в приледниковых зонах активных глубинных разломов из-за неравномерного воздымания отдельных участков территории при горообразовании, обуславливающего напряженно-деформированное состояние среды, концентрацию гравитационной энергии и последующее разрушение коренных пород приледниковых зон. Установлено, что механические, физические и геохимические поля, как неотъемлемые признаки-индикаторы проявлений и основа методологических обоснований исследований геодинамических процессов, оказывают долговременное влияние на породы на всех уровнях породообразования, формируя современную кору выветривания, и обуславливая интенсивное накопление четвертичных отложений. Определен режим среднестатической геоэкологической эволюции территории, который определяется соотношением скоростей прироста гор и темпов денудации. Делается вывод, что комплекс сопутствующих признаков – индикаторов представляют собой абиотические факторы геоэкологической среды, особого биотопа, где зарождается определенная популяция биоценоза с эндемической зависимостью к этим условиям A scientifically established forecast of the geoecological evolution of areas based on the analysis of the causal relationship of endogenous and exogenous processes is a relevant task of ensuring the safety of vacationers and planning the long-term development of high-mountain tourist and recreational complexes. Aim. The aim of the research is a long-term forecast of the geoecological evolution of the area based on the factors of geodynamic development and their signs in geophysical fields. To achieve this goal, the following tasks were solved: analysis of modern ideas about the impact of endogenous geodynamic processes on changes in the natural environment of mountain areas and the definition of the geodynamic concept of geoecological dependence; methodological substantiation of the manifestations of geophysical fields-indicators of tectonomagmatic processes and the choice of methods for their study, identification of zones of active faults and neotectonic manifestations. Methods. Materials of research by methods of converted waves of earthquakes, gravimagnetometry, microseismic sounding, electro-tomography, refracted seismic waves, geolocation were used. Results. As a result of the research, it is concluded that geoecological changes are caused by fracture neotectonics in the periglacial zones of active deep faults due to uneven uplift of certain parts of the territory during mountain building, which causes the stress-strain state of the environment, the concentration of gravitational energy and the subsequent destruction of the bedrock of the periglacial zones. It has been determined that mechanical, physical and geochemical fields, as integral indicators of manifestations and the basis of methodological substantiation of studies of geodynamic processes, have a long-term effect on rocks at all levels of rockforming, creating the modern weathering crust, and causing an intensive accumulation of Quaternary sediments. The mode of average static geoecological evolution of the area is defined. It is determined by the ratio of the growth rates of mountains and the rates of denudation. One can draw a conclusion that the complex of accompanying signs-indicators is abiotic factors of geoecological environment, a special biotope, where a certain population of biocenosis with endemic dependence to these conditions arises
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André, Marie-Françoise. "La livrée périglaciaire des paysages polaires : l'arbre qui cache la forêt ?/The periglacial scenery of polar areas: a smoke-screen ?" Géomorphologie : relief, processus, environnement 5, no. 3 (1999): 231–51. http://dx.doi.org/10.3406/morfo.1999.990.
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Giraudi, Carlo. "Late Holocene glacial and periglacial evolution in the upper Orco Valley, northwestern Italian Alps." Quaternary Research 71, no. 1 (January 2009): 1–8. http://dx.doi.org/10.1016/j.yqres.2008.08.004.
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AbstractThe sediments present in some areas of the Orco Valley provide indications on climatic variations that occurred during the last 6000 years on the southern slopes of the Alps. In particular, distribution and ages of peat layers help define periods and extent of glacial fluctuation in the last 2200 years. Sampling of soils involved in periglacial processes provided a basis for development of a chronological framework of late Holocene environmental change. The data indicate a trend toward cooler climate in the second half of the Holocene. A strong relationship exists between phases of River Po flooding and expansion/retreat phases of the Swiss glaciers: major glacial advances were coeval with periods of intense flooding of the River Po, whereas the phases of glacial retreat coincided with periods of little flooding of the Po. Only in three cases do relationships between glacier activity and floods show weak correlations; two of the cases relate to the warmest periods in approximately the last 2200 years, while the third is the present period. Paleoclimatic evidence from the study region indicates the relatively warm Roman Period between about 2200 and 1900 cal yr BP appears to better represent modern conditions than does the Medieval Warm Period.
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Morino, Costanza, Susan J. Conway, Matthew R. Balme, Jón Kristinn Helgason, Þorsteinn Sæmundsson, Colm Jordan, John Hillier, and Tom Argles. "The impact of ground-ice thaw on landslide geomorphology and dynamics: two case studies in northern Iceland." Landslides 18, no. 8 (May 4, 2021): 2785–812. http://dx.doi.org/10.1007/s10346-021-01661-1.
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AbstractAs consequence of ongoing climate change, permafrost degradation is thought to be increasingly affecting slope stability in periglacial environments. This is of growing concern in Iceland, where in the last decade, permafrost degradation has been identified among the triggering factors of landslides. The role of ground ice in conditioning the morphology and dynamics of landslides involving loose deposits is poorly understood. We show the geomorphological impact of the Móafellshyrna and Árnesfjall landslides that recently occurred in ice-cemented talus deposits in northern Iceland. Using field and aerial remote-sensing measurements of the morphological and morphometric characteristics of the landslides, we assess the influence of thawing ground ice on their propagation style and dynamics. The two mass movements are complex and are similar to rock- and debris-ice avalanches, changing trajectory and exhibiting evidence of transitioning their style of motion from a dry granular mass to a debris flow-like movement via multiple pulses. We infer that the thawing of ground ice together with the entrainment of saturated material provided the extra fluid causing this change in dynamics. The hazardous consequences of permafrost degradation will increasingly affect mountain regions in the future, and ground-ice thaw in steep terrain is a particularly hazardous phenomenon, as it may induce unexpected long-runout failures and can cause slope instability to continue even after the landslide event. Our study expands our knowledge of how landslides develop in unstable ice-cemented deposits and will aid assessment and mitigation of the hazard that they pose in Iceland and other mountainous periglacial areas.
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Ermolin, Evgeniy, Hernán De Angelis, and Pedro Skvarca. "Mapping of permafrost on Vega Island, Antarctic Peninsula, using satellite images and aerial photography." Annals of Glaciology 34 (2002): 184–88. http://dx.doi.org/10.3189/172756402781817824.
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AbstractThe work presented deals with detailed mapping of permafrost in Devil Bay, Vega Island, northeastern Antarctic Peninsula. Mapping of landforms and permafrost features within a periglacial plain was performed using high resolution visible satellite images and aerial photography. Two maps of permafrost were produced: one based on analysis and interpretation of visible satellite imagery and another on low-altitude aerial photography, both yielding similar results. The principles of morphogenesis were applied to map production, distinguishing both the syncryogenic and epicryogenic formations and each constitutive cryofacies. The interpretation of remote-sensing data allowed areas of occurrence of particular cryogenic processes to be defined. Remote sensing was found to be useful for permafrost mapping at both medium and large scales, and applicable for future extension to other regions in Antarctica.
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Roberts, M. B., M. R. Bates, C. Bergman, A. P. Currant, J. R. Haynes, R. Macphail, A. McConnell, R. Scaife, R. Unger-Hamilton, and R. C. Whatley. "Excavation of the Lower Palaeolithic Site at Amey's Eartham Pit, Boxgrove, West Sussex: A Preliminary Report." Proceedings of the Prehistoric Society 52 (1986): 215–45. http://dx.doi.org/10.1017/s0079497x00006666.
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The acheulian site at Boxgrove contains one of the most extensive areas of in situ fauna and flintwork yet discovered in Britain. This material is found in a complex sequence of sediments which represent depositional conditions from a 42 m sea level rise to the onset of a full periglacial climate. Excavation of the archaeological horizon has been accompanied by a programme of multidisciplinary research examining site formation processes, palaeolandscape and palaeoecological development, using sedimentological and environmental reconstruction techniques. Dating of the site is tentative as no absolute dates are available at present. However, comparative analysis with other British sites would suggest a position for the Boxgrove sequence within the Middle Pleistocene. The archaeological horizon is interpreted as being deposited towards the latter part of an interglacial or an interstadial period.
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Fischer, L., R. S. Purves, C. Huggel, J. Noetzli, and W. Haeberli. "On the influence of topographic, geological and cryospheric factors on rock avalanches and rockfalls in high-mountain areas." Natural Hazards and Earth System Sciences 12, no. 1 (January 31, 2012): 241–54. http://dx.doi.org/10.5194/nhess-12-241-2012.
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Abstract. The ongoing debate about the effects of changes in the high-mountain cryosphere on rockfalls and rock avalanches suggests a need for more knowledge about characteristics and distribution of recent rock-slope instabilities. This paper investigates 56 sites with slope failures between 1900 and 2007 in the central European Alps with respect to their geological and topographical settings and zones of possible permafrost degradation and glacial recession. Analyses of the temporal distribution show an increase in frequency within the last decades. A large proportion of the slope failures (60%) originated from a relatively small area above 3000 m a.s.l. (i.e. 10% of the entire investigation area). This increased proportion of detachment zones above 3000 m a.s.l. is postulated to be a result of a combination of factors, namely a larger proportion of high slope angles, high periglacial weathering due to recent glacier retreat (almost half of the slope failures having occurred in areas with recent deglaciation), and widespread permafrost occurrence. The lithological setting appears to influence volume rather than frequency of a slope failure. However, our analyses show that not only the changes in cryosphere, but also other factors which remain constant over long periods play an important role in slope failures.
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Caisová, Lenka, Tomáš Bešta, Jiří Chlachula, Jiří Komárek, and Štěpán Husák. "Taxonomic investigations of cyanobacterial and algal flora from the Southern Altai, East Kazakhstan." Biodiversity: Research and Conservation 15, no. 1 (January 1, 2009): 13–22. http://dx.doi.org/10.2478/v10119-009-0021-3.
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Taxonomic investigations of cyanobacterial and algal flora from the Southern Altai, East KazakhstanThe study presents results of pilot investigations (2005-2007) of micro-vegetation biodiversity in marginally explored mountain and forest-steppe areas of southern Altai, East Kazakhstan. On the basis of morphological phenotypes and ecological demands a total of 351 taxa of cyanobacteria and algae were identified in the principal biotopes (rivers and streams, backwaters, irrigation channels, lakes, high-tundra periglacial and barren land settings, snow fields, and pedogenic /soil cover/environments) of the territorial topographic gradient of ca. 400-3900 m a.s.l. Microbiological records display a remarkable taxonomic variability, including several previously undescribed endemic species of algae adapted to locally specific geoenvironmental conditions. The present results show a major potential for future systematic phycological studies integrated in the complex nature monitoring and management strategy in protected areas of the Altai. The results also demonstrate a limited impact of modern human activity on the quality of local water sources with only minor present ecological risks in balance with the traditional lifestyles of pastoralist communities.
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Sileo, Noelia R., Cristina Dapeña, and Dario Trombotto Liaudat. "Isotopic composition and hydrogeochemistry of a periglacial Andean catchment and its relevance in the knowledge of water resources in mountainous areas." Isotopes in Environmental and Health Studies 56, no. 5-6 (September 21, 2020): 480–94. http://dx.doi.org/10.1080/10256016.2020.1814278.
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Flowers, Gwenn E., Helgi Björnsson, and Finnur Pálsson. "New insights into the subglacial and periglacial hydrology of Vatnajökull, Iceland, from a distributed physical model." Journal of Glaciology 49, no. 165 (2003): 257–70. http://dx.doi.org/10.3189/172756503781830827.
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AbstractWe apply a time-dependent distributed glaciohydraulic model to Vatnajökull ice cap, Iceland, aiming to determine the large-scale subglacial drainage structure, the importance of basally derived meltwater, the influence of a permeable glacier bed and Vatnajökull’s discharge contribution to major rivers in Iceland. The model comprises two coupled layers that represent the subglacial horizon perched on a subsurface aquifer in the western sector and bedrock in the eastern sector. To initialize and drive the simulations, we use digital elevation models of the ice surface and bed, the 1999/2000 measured mass balance and an estimate of subglacial geothermal heat fluxes. The modelled subglacial flow field differs substantially from that derived by hydraulic-potential calculations, and the corresponding distribution of basal effective pressure shows a strong correlation between low effective pressure and surge-prone areas in northeastern and southern sectors of Vatnajökull. Simulations suggest that geothermally derived basal melt may account for up to ∼5% of the annual glacial discharge, and buried aquifers may evacuate up to ∼30% of subglacialwater.Time-dependent tests yield estimates of the glacial discharge component in various outlet rivers and suggest a possible seasonal migration of subglacial hydraulic divides. This study of present-day Vatnajökull hydrology forms the starting point for investigations of its future evolution.
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Senderak, Krzysztof, Marta Kondracka, and Bogdan Gądek. "Postglacial talus slope development imaged by the ERT method: comparison of slopes from SW Spitsbergen, Norway and Tatra Mountains, Poland." Open Geosciences 11, no. 1 (December 31, 2019): 1084–97. http://dx.doi.org/10.1515/geo-2019-0084.
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Abstract Talus slopes are a common sedimentary formation both in polar and high-mountain areas, but their development is still not sufficiently understood. This article discusses the environmental factors that have been influencing development of talus slopes since the deglaciation and their impact on the internal structure of slopes. Case studies of the slopes from SW Spitsbergen and the Tatra Mountains in Poland were compared in order to explore different evolution stages. Slopes’ structure was analysed using geophysical surveys based on two-dimensional electrical resistivity tomography (ERT) with a Wenner-Schlumberger array and an electrode spacing of 5 m, combined with geomorphological observations. The investigated talus slopes represent the paraglacial, periglacial and talus-alluvial environments. New data on the internal structure of talus slopes developing in the present or past glaciated areas adds to understanding talus slope evolution. There are many different views concerning the development of slopes during the paraglacial period, whose analysis seems to be crucial in the background of climate change and their record in slope structures. In addition, the study provided valuable information on the development and degradation of permafrost in slope materials.