Journal articles: 'Periglacial phenomena'

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NEŠIĆ, Dragan, Uroš V. MILINČIĆ, and Miroljub A. MILINČIĆ. "PERIGLACIAL RELIEF PHENOMENA ON MOUNT VARDENIK (SOUTHEASTERN SERBIA)." Carpathian Journal of Earth and Environmental Sciences 18, no. 1 (January 25, 2023): 127–38. http://dx.doi.org/10.26471/cjees/2023/018/246.

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In the medium-high mountains of Serbia (1,000-2,000 m.a.s.l), sporadic periglacial relief forms occur, which is also the case with Mount Vardenik (1,876 m.high), a mountain in the southeast of Serbia. During reconnaissance, certain relict and sub-recent periglacial phenomena and landforms in the highest part of the mountain have been identified: block slides, rock flows, thermogenic landslides in springs, nivation-induced relief and in one location cryoplanation terraces. Sparsely clustered and individual occurrences of frost splitting and solifluction of the land surface and small areas with grass turf indicate contemporary signs of sporadically present seasonal frost and freeze-thaw cycles. Periglacial morphology and its processes have been recorded and investigated using a qualitative geomorphological procedure. The main problem is the origin of periglacial phenomena (occurrences and landforms) of the relief, considering that the analysis of the contemporary climate, geoecological properties and anthropogenic activities indicate that there are no condi-tions for the existence and development of a contemporary periglacial environment on the mountain. The problem was analyzed considering the climate change in general and, in particular, geoecological conditions created under the influence of human activities. Due to the observed sporadic relict and sub-recent periglacial relief on Mount Vardenik, in contemporary conditions the periglacial environment of this area can be consid-ered as relict or as a phenomenon bordering the limits of differentiation. The relict property also results from the fact that on the mountain, due to the contemporary climate and changed geoecological conditions, the transition zone of the periglacial environment cannot be distinguished.

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Hamelin, Louis-Edmond. "Cartographie géomorphologique appliquée au périglaciaire." Cahiers de géographie du Québec 7, no. 14 (April 12, 2005): 193–209. http://dx.doi.org/10.7202/020426ar.

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The writer proposes a simple and practical set of symbols for use in the preparation of periglacial maps. These maps can he constructed rapidly and at modest cost. In a preliminary section dealing with cartographie principles, the writer proposes that jour aspects of periglacial studies he mapped ; phenomena, « conditions », regions, and aspects of applied periglacial studies. Attention will also he given to chronology. Symbolisation conforms to the following scheme : drawings or designs for phenomena, lines and curves for conditions, line patterns for regions, and letters to indicate aspects of applied periglacial studies. Colours can he used where more than one cold period has occurred. The writer proposes in Table I (in pocket) the use of more than one hundred symbols for the representation, on a 1:50,000 base map, of periglacial phenomena. The problems of classification of periglacial phenomena are also discussed, with the writer suggesting a classification based upon group of process. Among the categories included are : gelisolation, gelifraction, gelifluction, nivalisation, action of floating ice, gelifluviation, wind action and polygonation. The text ends with a glossary of periglacial terms.

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SVENSSON, HARALD. "Geophysical aspects on periglacial phenomena." Boreas 20, no. 1 (January 16, 2008): 16. http://dx.doi.org/10.1111/j.1502-3885.1991.tb00454.x.

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Soons, J. M., and L. W. Price. "Periglacial phenomena in New Zealand." Permafrost and Periglacial Processes 1, no. 2 (August 3, 2006): 145–59. http://dx.doi.org/10.1002/ppp.3430010206.

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Niini, H., N. Marcos, and T. Ruskeeniemi. "Periglacial phenomena affecting nuclear waste disposal." Bulletin of the Geological Society of Finland 69, no. 1-2 (December 1997): 109–14. http://dx.doi.org/10.17741/bgsf/69.1-2.009.

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BUTZER, KARL W. "Pleistocene ‘periglacial’ phenomena in southern Africa." Boreas 2, no. 1 (January 16, 2008): 1–11. http://dx.doi.org/10.1111/j.1502-3885.1973.tb00245.x.

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Nesic, Dragan, and Srdjan Belij. "Some observations about solifluctional scars as recent phenomena on the lower altitudinal limit of the periglacial climazonal belt." Glasnik Srpskog geografskog drustva 94, no. 4 (2014): 59–76. http://dx.doi.org/10.2298/gsgd1404059n.

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This paper presents the morphological and genetical characteristics of small forms of modern periglacial environment of the Balkan Peninsula mountains, called solifluctional scars. Except several previous observations, these forms have not been distinguished and considered as a type of a modern periglacial relief so far. Solifluctional scars are small phenomena of the horseshoe indentations in the pedological-vegetational base of the decimetermeter dimensions. They are formed by cleavage of the base by the use of a solifluctional sliding process with secondary processes of frost and linear water denudation during their subsequent evolution. As such, they can be seen as rudimentary phenomena of beginnings of linear flows of snowmelt, as well as a small mud solifluctionaltorrential flows, but also in general, as a segment of cryoplanation. These qualities classify them into a frame of rudimentary phenomena at the lower limit of the periglacial climazonal belt in the Balkan Peninsula mountains.

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Křížek, Marek. "Surface and Undersurface Phenomena in the Čecher Hill in the Hostýnské vrchy Hills." Geografie 104, no. 3 (1999): 201–8. http://dx.doi.org/10.37040/geografie1999104030201.

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The author describes surface and undersurface landforms in the Čecher Hill (the Outer Western (Flysch) Carpathians) and outlines their origin and development. The main part of the article focuses on periglacial and pseudokarst (above all a pseudokarst cave in the Čecher Hill) landforms in this area. It also describes periglacial processes in the Pleistocene and the processes of humid character in the Holocene, which formed these landforms. The author takes notice of the relationship between landforms and geological conditions in the area.

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Grab, Stefan. "Glacial and periglacial phenomena in Ethiopia: a review." Permafrost and Periglacial Processes 13, no. 1 (2002): 71–76. http://dx.doi.org/10.1002/ppp.405.

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Hamelin, Louis-Edmond. "Périglaciaire du Canada : idées nouvelles et perspectives globales." Cahiers de géographie du Québec 5, no. 10 (April 12, 2005): 141–203. http://dx.doi.org/10.7202/020308ar.

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Periglacial conditions which occur in Canada have been studied recently. Most of the research has been so jar limited in scope (mostly patterned ground and permafrost), undertaken for practical purposes (v.g. airport strips and the new Aklavik's site) and often carried by governmental agencies. Though a hundred titles or so of various articles and notes could be cited in a bibliographical survey of the topic, it must be underlined that the inventory of periglacial phenomena itself is still jar from being completed. This paper, prepared for the Canadian Committee of the International Commission of Periglacial Geomorphology, is based on a broad conception of the topic. The author suggests a useful series of new analytical concepts and outlines new fields for future research. The paper deals with three major aspects of periglacial studies : processes, datation and regions. Some of the processes and conditions are : terrain, wind, vegetation, the climatic « facies » (frozen ground, snow, air temperature and floating ice System). The author feels that all periglacial phenomena in Canada can be classified within a chronological sequence which he makes an attempt to establish as follows : a) Lower and Middle Wisconsin ; b) Pleniwisconsin ; c) Finiwiscon-sin ; d) Late Glacial ; and, e) Recent. Canada, in the opinion of Dr. Hamelin, can be divided into eleven periglacial « provinces ». The first jour provinces : Elizabeth, Victoria, Keewatin and Innuit are closely associated with continuous permafrost. Three provinces, Hudson, Labrador and Mackenzie, are situated in the periarctic zone. Two, Alberta and Saint-Laurent, have a southern situation along the parallel 50°N. Finally, two provinces : Yukon and Columbia, lie within the limits of Western Cordillera. These eleven provinces are proposed to serve for the designation of periglacial types or regimes throughout the cold regions of the world. The paper concludes with a glossary of new terms suggested for adoption.

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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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12

Humlum, Ole, and Hanne H. Christiansen. "Mountain climate and periglacial phenomena in the Faeroe Islands." Permafrost and Periglacial Processes 9, no. 3 (July 1998): 189–211. http://dx.doi.org/10.1002/(sici)1099-1530(199807/09)9:3<189::aid-ppp287>3.0.co;2-n.

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13

Krummenacher, Bernhard, and Klaus Budmiger. "Monitoring of periglacial phenomena in the furggentälti Swiss Alps." Permafrost and Periglacial Processes 3, no. 2 (April 1992): 149–55. http://dx.doi.org/10.1002/ppp.3430030213.

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Urdea, Petru. "Rock glaciers and periglacial phenomena in the southern Carpathians." Permafrost and Periglacial Processes 3, no. 3 (July 1992): 267–73. http://dx.doi.org/10.1002/ppp.3430030317.

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Nesic, Dragan, and Uros Milincic. "The lower altitudinal limit of the periglacial climazonal belt on Kopaonik Mountain (Serbia)." Glasnik Srpskog geografskog drustva 99, no. 1 (2019): 1–18. http://dx.doi.org/10.2298/gsgd1901001n.

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The morphostructural relief of the highest parts of the central Kopaonik Mt was altered by exogenous agents, by denudation as a primary and periglacial processes as a secondary agent. Previous geomorphological studies were mostly focused on the traces of the Pleistocene glaciation, although no reliable evidence was found for this. Recent research, in the part of the mountain above 1,700 m of absolute height, points to geomorphological phenomena resulting from more recent processes within the periglacial environment. By means of geomorphological reconnaissance, analysis and mapping of the highest part of the Kopaonik mountain massif, forms of relief were studied, the ones that according to their morphology correspond to the periglacial forms and processes described in the conditions of high latitudes and high mountains. Determining the spatial coverage of the periglacial belt, especially its lower limit on Kopaonik Mt, is important for understan-ding the distribution of this climatic morphology both in Serbia and in South East Europe. The research contributes to one of the primary aims of exploring the concept of the periglacial zone, in terms of the regional distribution of its specific relief forms.

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16

Vandenberghe, J. "Periglacial phenomena and pleistocene environmental conditions in the Netherlands—An overview." Permafrost and Periglacial Processes 3, no. 4 (October 1992): 363–74. http://dx.doi.org/10.1002/ppp.3430030410.

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17

Vasconez, Francisco J., Luis Maisincho, S. Daniel Andrade, Bolivar Cáceres, Benjamin Bernard, Cristina Argoti, Edwin Telenchana, Marco Almeida, Stefanie Almeida, and Verónica Lema. "Secondary Lahars Triggered by Periglacial Melting at Chimborazo Volcano, Ecuador." Revista Politécnica 48, no. 1 (July 31, 2021): 19–30. http://dx.doi.org/10.33333/rp.vol48n1.02.

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Periglacial melting processes can provide the water source for secondary lahars triggered by volcanic and/or meteorological phenomena on volcanoes. Between December 2015 and April 2016, four major lahars were reported southeast of Chimborazo volcano (Ecuador). Fieldwork allowed determining the area (1.670.37 km2), volume (3E+05 to 7E+05 m3), peak discharge (100 - 150 m3/s) and mean speed (2 - 4 m/s) of these flows, which affected the local infrastructure and threatened several towns downstream (>1000 inhabitants). This case study suggests that anomalous periglacial melting could have been induced by: i) an increase in temperatures at periglacial altitudes partly ascribed to El Niño phenomenon, ii) albedo reduction of the glacier due to ash fallout from Tungurahua volcano (40 km east of Chimborazo) which erupted from 1999 to 2016 and, iii) a slight increase in internal activity at Chimborazo prior and during the lahars occurrence, as evidenced by more seismic events and thermal anomalies. These simultaneous factors could have led to the formation, outburst and/or overflow of superficial and intra-glacier ponds providing the water source to generate lahars on a dormant volcano.

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18

HIRAKAWA, Kazuomi. "A Comparative Observation of Periglacial Landforms and Phenomena in Iceland, Spitzbergen and Hokkaido." Journal of Geography (Chigaku Zasshi) 103, no. 4 (1994): 421–23. http://dx.doi.org/10.5026/jgeography.103.4_421.

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19

Nikiforov, S. L., R. A. Ananiev, N. V. Libina, N. N. Dmitrevskiy, and L. I. Lobkovskii. "Ice gouging on the arctic shelf of Russia." Океанология 59, no. 3 (June 26, 2019): 466–68. http://dx.doi.org/10.31857/s0030-1574593466-468.

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The results of recent geological and geophysical expeditions indicate the activation of hazardous natural phenomena associated with ice gouging and represent geohazard for almost all activities, including operation of the Northern Sea Route. Within the Barents Sea and the western part of the Kara Sea, the modern ice gouging is mainly associated with icebergs which are formed as a result of the destruction of the glaciers of Novaya Zemlya, the Spitsbergen archipelago and Franz Josef Land, while on the eastern shelf it is caused by the destruction of seasonal or perennial ice fields. Fixed furrows can be divided into modern coastal gouges or deep water ploughmarks. All deep water gouges within the periglacial and glacial shelf are of paleogeographical origin, but with different mechanisms of action on the seabed. These furrows were formed by floating ice on the periglacial shelf. On the glacial shelf deep water ploughmarks were formed by large icebergs, which could carry out the gouging even on the continental slope and deep-sea ridges of the Arctic Ocean.

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20

Niessen, Arjan, Peter Van Horssen, and Eduard A. Koster. "Altitudinal Zonation of Selected Geomorphological Phenomena in an Alpine Periglacial Area (Abisko, Northern Sweden)." Geografiska Annaler. Series A, Physical Geography 74, no. 2/3 (1992): 183. http://dx.doi.org/10.2307/521295.

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Niessen, Arjan, Peter Van Horssen, and Eduard A. Koster. "Altitudinal Zonation of Selected Geomorphological Phenomena in an Alpine Periglacial Area (Abisko, Northern Sweden)." Geografiska Annaler: Series A, Physical Geography 74, no. 2-3 (August 1992): 183–96. http://dx.doi.org/10.1080/04353676.1992.11880361.

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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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Angiel, Piotr. "Geographical Research of the 30th Polish Antarctic Expedition at Arctowski Polish Station (King George Island, South Shetland Islands, Antarctica)." Miscellanea Geographica 13, no. 1 (December 1, 2008): 51–56. http://dx.doi.org/10.2478/mgrsd-2008-0005.

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Abstract This paper presents the scope of geographical research conducted at Arctowski Station during the 30th Polish Antarctic Expedition. The research included meteorological, climatological, geomorphological and glaciological issues. During the expedition, research was conducted on sandur sediments on the outwash plain of Sphinx Glacier, the size of the aeolian transport, intensity of periglacial phenomena, and the way in which environmental conditions are recorded on quartz grains collected on the Admiralty Bay beaches. Detailed measurements of the basic meteorological components were made, geomorphological maps of the outwash plains of Sphinx, Baranowski, and Windy Glaciers were also completed.

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Kerguillec, Riwan. "Characteristics and altitudinal distribution of periglacial decay phenomena in the massif of rondane, central norway." Geografiska Annaler: Series A, Physical Geography 97, no. 2 (June 2015): 299–315. http://dx.doi.org/10.1111/geoa.12066.

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KONDO, Reisuke. "Formation Age of Fossil Periglacial Phenomena in Northern Hokkaido, Japan, Using OSL and AMS14C Dating." Journal of Geography (Chigaku Zasshi) 120, no. 3 (2011): 547–56. http://dx.doi.org/10.5026/jgeography.120.547.

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26

Groos, Alexander R., Janik Niederhauser, Luise Wraase, Falk Hänsel, Thomas Nauss, Naki Akçar, and Heinz Veit. "The enigma of relict large sorted stone stripes in the tropical Ethiopian Highlands." Earth Surface Dynamics 9, no. 2 (March 12, 2021): 145–66. http://dx.doi.org/10.5194/esurf-9-145-2021.

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Abstract. Large forms of sorted patterned ground belong to the most prominent geomorphic features of periglacial and permafrost environments of the mid-latitudes and polar regions, but they were hitherto unknown in the tropics. Here, we report on relict large sorted stone stripes (up to 1000 m long, 15 m wide, and 2 m deep) on the ca. 4000 m high central Sanetti Plateau of the tropical Bale Mountains in the southern Ethiopian Highlands. These geomorphic features are enigmatic since forms of patterned ground exceeding several metres are commonly associated with distinct seasonal ground temperatures, oscillating around 0 ∘C. To systematically investigate present frost phenomena and relict periglacial landforms in the Bale Mountains, we conducted extensive geomorphological mapping. The sorted stone stripes were studied in more detail by applying aerial photogrammetry, ground-penetrating radar measurements, and 36Cl surface exposure dating. In addition, we installed ground temperature data loggers between 3877 and 4377 m to analyse present frost occurrence and seasonal ground temperature variations. Superficial nocturnal ground frost was measured at 35–90 d per year, but the ground beneath the upper few centimetres remains unfrozen the entire year. Seasonal frost occurrence would require a mean annual ground temperature depression of about 11 ∘C, corresponding to an air temperature decrease of about 6–8 ∘C (relative to today) as inferred from a simple statistical ground temperature model experiment. Our results suggest the formation of the large sorted stone stripes under past periglacial conditions related to lateral and vertical frost sorting in the course of cyclic freezing and thawing of the ground. It is likely that the stone stripes formed either in proximity to a former ice cap on the Sanetti Plateau over the last glacial period due to seasonal frost heave and sorting or they developed over multiple cold phases during the Pleistocene. Although certain aspects of the genesis of the large sorted stone stripes remain unresolved, the presence of these geomorphic features provides independent evidence besides glacial landforms for unprecedented palaeoclimatic and palaeoenvironmental changes in the tropical Bale Mountains during the (Late) Pleistocene.

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Gómez-Lende, Manuel, and Manuel Sánchez-Fernández. "Cryomorphological Topographies in the Study of Ice Caves." Geosciences 8, no. 8 (July 26, 2018): 274. http://dx.doi.org/10.3390/geosciences8080274.

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The current interest in ice caves requires that their varied manifestations be known as accurately as possible in view of their responses to a global change and also to their great potential as paleoenvironmental witnesses. This phenomenon has been known about for a long time but is still scarcely studied from the point of view of its cryological values and the evolution and distribution of many of their morphologies. For this, the development of cryomorphological topographies from traditional techniques to geodetic surveys with different tools, including terrestrial laser scanning, is one of the most current ways to characterize and quantify this type of cryospheric phenomena. It represents a new kind of periglacial cartography whose use is feasible in spite of the difficulties these environments present.

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Vandenberghe, J. "Paleoenvironment and Stratigraphy during the Last Glacial in the Belgian-Dutch Border Region." Quaternary Research 24, no. 1 (July 1985): 23–38. http://dx.doi.org/10.1016/0033-5894(85)90081-x.

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The Weichselian deposits of the flat Dutch-Belgian coversand area are characterized by highly varying facies types. The geomorphological location and the role of water during the deposition and the transportation of the original eolian sediments may fully explain the texture and sedimentary structures of the lithostratigraphic units. Directly deposited eolian loams and sands on the dry interfluves contrast with the same, but reworked, sediments in wet valleys and depressions. The formation of periglacial phenomena is also dependent on the geomorphologic, lithologic, and hydrologic conditions. The occurrence of peaty beds is restricted to wet environments without precise climatic significance. The Pleniglacial sequence is subdivided into early and late Pleniglacial stades, both characterized by (partial) permafrost conditions, interrupted by a middle Pleniglacial interstadial complex with clearly milder conditions.

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Kleman, Johan, and Ingmar Borgstrom. "The Boulder Fields of Mt. Fulufjallet, West-Central Sweden -Late Weichselian Boulder Blankets and Interstadial Periglacial Phenomena." Geografiska Annaler. Series A, Physical Geography 72, no. 1 (1990): 63. http://dx.doi.org/10.2307/521238.

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Alberti, Stefano, and Luca Flessati. "Rock Glacier Dynamics by a Thermo-Elastic-Viscoplastic Constitutive Relationship." Geosciences 11, no. 10 (October 7, 2021): 417. http://dx.doi.org/10.3390/geosciences11100417.

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As a result of mountain permafrost creep, rock glaciers are common features in high-altitude periglacial areas. From a practical point of view, beyond their localization and inventorying, both the monitoring and prediction of their evolution due to climate changes are crucial. One of the effects of climate change is the thickening of the basal shear zone (the portion of the rock glacier where most deformations are localized), eventually leading to the development of unexpected and unprecedented (in terms of location, magnitude, frequency, and timing) instability phenomena. These phenomena bear consequences for the understanding of landscape evolution, natural hazards, and the safe and sustainable operation of high-mountain infrastructures. Most of the studies about active rock glaciers are focused on the analysis of monitoring data, while just a few studies are focused on modeling their behavior to understand their possible further evolution. The active rock glacier response is characterized by a viscous (rate-dependent) behavior, influenced by seasonal temperature oscillations, and characterized by a seasonal transition from slow to fast. In this work, a new thermo-mechanical model based on the delayed plasticity theory and calibrated on experimental results is proposed. The model is employed to evaluate the influence of geometry and forcing (air temperature) on a real rock glacier (Murtèl-Corvatsch rock glacier) creep behavior.

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Higuchi, Shigeo. "Morteratsch glacier in eastern Switzerland, glacial sediments at Bittelschiess in southern Germany, and fossil periglacial phenomena at Bosscherheide in southern Netherland." Journal of the Geological Society of Japan 102, no. 1 (1996): I—II. http://dx.doi.org/10.5575/geosoc.102.i.

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Misyurkeeva, Natalya, Igor Buddo, Gleb Kraev, Aleksandr Smirnov, Alexey Nezhdanov, Ivan Shelokhov, Anna Kurchatova, and Andrei Belonosov. "Periglacial Landforms and Fluid Dynamics in the Permafrost Domain: A Case from the Taz Peninsula, West Siberia." Energies 15, no. 8 (April 11, 2022): 2794. http://dx.doi.org/10.3390/en15082794.

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Most of the developing oil and gas fields in Russia are located in Arctic regions and constructed on permafrost, where recent environmental changes cause multiple hazards for their infrastructure. The blowing-up of pingos, resulting in the formation of gas emission craters, is one of the disastrous processes associated both with these external changes and, likely, with deep sources of hydrocarbons. We traced the channels of fluid migration which link a gas features reservoirs with periglacial phenomena associated with such craters with the set of geophysical methods, including common depth point and shallow transient electromagnetic methods, on an area of a prospected gas field. We found correlated vertical anomalies of acoustic coherence and electrical resistivity associated with gas chimneys in the upper 500–600 m of the section. The thickness of the ice-bonded permafrost acting as a seal for fluids decreased in the chimney zone, forming 25–50 m deep pockets in the permafrost base. Three pingos out of six were located above chimneys in the study area of 200 km2. Two lakes with parapets typical for craters were found. We conclude that the combination of applied methods is efficacious in terms of identifying this type of hazard and locating potentially hazardous objects in the given territory.

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Namzalov, Bimba, and Nikolay Dubrovsky. "About relict larches of mountain forest steppe of South Siberia." BIO Web of Conferences 24 (2020): 00060. http://dx.doi.org/10.1051/bioconf/20202400060.

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The paper provides original information about relict phenomena in the structure of the forest component of the mountain forest-steppe of Southern Siberia (SS). Larch (Larix sibirica Ledeb.) shrub-grass forests are a characteristic element of vegetation in the forest-steppe of the SS. The oldest are the Pliocene, the most thermophilic analogues of the modern forest-steppe, noted in the foothills of the Western Tannu-Ola ridge (natural boundary Khorlety) – is a small-leaved honeysuckle-wormwood larch forest with participation in the community of highland-Asian elements of ancient Middle-earth – Lonicera microphylla, Cotoneaster megalocarpus, Spiraea hypericifolia. In the conditions of Western Transbaikalia, in the spurs of the Malyi Khamar-Daban ridge (natural boundary Inzagatuy) described the relict sedge-needlegrass larch forest with the participation of characteristic species of the periglacial Pleistocene complex such as Helictotrichon altaicum, Festuca sibirica, Artemisia commutata and others. In the Quaternary period – especially in the xerothermic phases of the Holocene, as mountain glaciers were deglaciated and a relatively warm and temperate climate develops, conditions are created for the formation of a modern mountain forest-steppe in the conditions of the semi-humid climatic regime of the SS.

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Rempel, Alan W. "Microscopic and environmental controls on the spacing and thickness of segregated ice lenses." Quaternary Research 75, no. 2 (March 2011): 316–24. http://dx.doi.org/10.1016/j.yqres.2010.07.005.

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AbstractThe formation of segregated ice is of fundamental importance to a broad range of permafrost and periglacial features and phenomena. Models have been developed to account for the microscopic interactions that drive water migration, and predict key macroscopic characteristics of ice lenses, such as their spacings and thicknesses. For a given set of sediment properties, the temperature difference between the growing and incipient lenses is shown here to depend primarily on the ratio between the effective stress and the temperature deviation from bulk melting at the farthest extent of pore ice. This suggests that observed spacing between ice lenses in frozen soils, or traces of lenses in soils that once contained segregated ice, might be used to constrain the combinations of effective stress and temperature gradient that were present near the time and location at which the lower lens in each pair was initiated. The thickness of each lens has the potential to contain even more information since it depends additionally on the rate of temperature change and the permeability of the sediment at the onset of freezing. However, these complicating factors make it more difficult to interpret thickness data in terms of current or former soil conditions.

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35

Brosche, Karl-Ulrich. "Wirkungen des pleistozänen kaltzeitlichen Klimas, insbesondere des Bodenfrostes, in den Sedimenten des östlichen Ostfalen (Raum Hannover - Wolfsburg - Helmstedt -Bad Harzburg - Salzgitter-Bad - Hannover) - Teil 1." E&G Quaternary Science Journal 46, no. 1 (January 1, 1996): 1–17. http://dx.doi.org/10.3285/eg.46.1.01.

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Abstract. In this first part of the publication - a second part especially about ice-wedges and aeolian processes will follow in the next year - the abundant form inventory of diversified periglacial solifluction layers, of horizons of gelifraction, of congelifractates, of frost kettles "Frostkessel", geologic "Stiche", of the "Hakenschlagen", of glacigen structures of icefoldings and of cryoturbation structures in eastern Lower Saxony (eastern part of Ostfalen) is photographed, described, explained and dated. Most parts of the forms can be found in probably Saalian (Drenthe) glacifluvial and morainic sediments. In the southern part of the loess border which divides the researched region in a northern and a southern part, the Saalian sediments are covered by loessic sediments of high Weichselian age. The loessic deposits are used for the datation of the older diversified solifluction layers as well as for the many cryoturbation phenomena. Mostly the formation of the latter sediments has just begun in the second part of the Saalian time. Recrding to the depth where the cryoturbation phenomenareach down, the mollisol in top of the permafrost had had an extensure of 1,0 to 1,5 m during the Upper Saalian and the whole Weichselian period.

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Hambrey, M. J. "M.J. Clark (ed.) 1988. Advances in Periglacial Geomorphology. The International Geographical Union Commission on the Significance of Periglacial Phenomena. xxiv + 481 pp. Chichester, New York, Brisbane, Toronto, Singapore: John Wiley. Price £55.00 (hard covers). ISBN 0 471 90981 5." Geological Magazine 126, no. 2 (March 1989): 202. http://dx.doi.org/10.1017/s0016756800006397.

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Błaszczyk, Małgorzata, Michał Laska, Agnar Sivertsen, and Shridhar D. Jawak. "Combined Use of Aerial Photogrammetry and Terrestrial Laser Scanning for Detecting Geomorphological Changes in Hornsund, Svalbard." Remote Sensing 14, no. 3 (January 26, 2022): 601. http://dx.doi.org/10.3390/rs14030601.

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The Arctic is a region undergoing continuous and significant changes in land relief due to different glaciological, geomorphological and hydrogeological processes. To study those phenomena, digital elevation models (DEMs) and highly accurate maps with high spatial resolution are of prime importance. In this work, we assess the accuracy of high-resolution photogrammetric DEMs and orthomosaics derived from aerial images captured in 2020 over Hornsund, Svalbard. Further, we demonstrate the accuracy of DEMs generated using point clouds acquired in 2021 with a Riegl VZ®-6000 terrestrial laser scanner (TLS). Aerial and terrestrial data were georeferenced and registered based on very reliable ground control points measured in the field. Both DEMs, however, had some data gaps due to insufficient overlaps in aerial images and limited sensing range of the TLS. Therefore, we compared and integrated the two techniques to create a continuous and gapless DEM for the scientific community in Svalbard. This approach also made it possible to identify geomorphological activity over a one-year period, such as the melting of ice cores at the periglacial zone, changes along the shoreline or snow thickness in gullies. The study highlights the potential for combining other techniques to represent the active processes in this region.

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Świątecki, Aleksander, Dorota Górniak, Marek Zdanowski, Jakub Grzesiak, and Tomasz Mieczan. "Polityczne i prawne aspekty prowadzenia badań naukowych w rejonach polarnych." Studia Prawnoustrojowe, no. 43 (October 26, 2019): 335–47. http://dx.doi.org/10.31648/sp.4644.

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The Arctic and Antarctic have been of great interest to the international community for a number of years. The still unresolved problem regardingpolar regions is the still partially regulated legal issues concerning the management of these areas. Both the Arctic and Antarctica are areas of potentiallygreat scientific, economic, political and military importance. The political and legal status of polar areas is not uniform. Currently, there is no legalinternational document that would regulate issues related to the management of the Arctic region. The political and legal status of Antarctica wasdetermined in 1959 in Washington. The Antarctic Treaty regulates in detail the activities in this region. Territorial claims are a particularly importantproblem. A number of countries prove their territorial rights to both the Arctic and Antarctic. The Arctic division is discussed within five countries,without the participation of the international community, while the Antarctic Treaty arrangements have put these issues on ice until 2049. Internationalcooperation in the field of research of polar regions has a long history and is confirmed by bilateral and international agreements. Conducted researchin the Arctic and Antarctic relate to various scientific problems. Investigations of processes taking place on Earth on a global scale are of particularimportance, both in historical and prognostic perspective. The history of Polish polar research is rich, multi-faceted and dates back to the second half ofthe nineteenth century. Contemporary Polish polar research focuses on a number of problems: glaciology and periglacial phenomena, climatology,geomorphology, hydrology, and geo-ecosystems dynamics. Polish scientific activity, in these regions, significantly develops our positive relations withthe international community.

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Michel, R. F. M., C. E. G. R. Schaefer, F. N. B. Simas, Francelino M. R., E. I. Fernandes-Filho, G. B. Lyra, and J. G. Bockheim. "Active layer thermal monitoring at Fildes Peninsula, King George Island, Maritime Antarctica." Solid Earth Discussions 6, no. 2 (July 1, 2014): 1423–49. http://dx.doi.org/10.5194/sed-6-1423-2014.

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Abstract. International attention to the climate change phenomena has grown in the last decade; the active layer and permafrost are of great importance in understanding processes and future trends due to their role in energy flux regulation. The objective of the this paper is to present active layer temperature data for one CALM-S site located at Fildes Peninsula, King George Island, Maritime Antarctica over an fifth seven month period (2008–2012). The monitoring site was installed during the summer of 2008 and consists of thermistors (accuracy of ± 0.2 °C), arranged vertically with probes at different depths, recording data at hourly intervals in a~high capacity data logger. A series of statistical analysis were performed to describe the soil temperature time series, including a linear fit in order to identify global trend and a series of autoregressive integrated moving average (ARIMA) models were tested in order to define the best fit for the data. The controls of weather on the thermal regime of the active layer have been identified, providing insights about the influence of climate chance over the permafrost. The active layer thermal regime in the studied period was typical of periglacial environment, with extreme variation at the surface during summer resulting in frequent freeze and thaw cycles. The active layer thickness (ALT) over the studied period showed variability related to different annual weather conditions, reaching a maximum of 117.5 cm in 2009. The ARIMA model was considered appropriate to treat the dataset, enabling more conclusive analysis and predictions when longer data sets are available. Despite the variability when comparing temperature readings and active layer thickness over the studied period, no warming trend was detected.

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Bergstedt, Helena, Benjamin M. Jones, Kenneth Hinkel, Louise Farquharson, Benjamin V. Gaglioti, Andrew D. Parsekian, Mikhail Kanevskiy, et al. "Remote Sensing-Based Statistical Approach for Defining Drained Lake Basins in a Continuous Permafrost Region, North Slope of Alaska." Remote Sensing 13, no. 13 (June 29, 2021): 2539. http://dx.doi.org/10.3390/rs13132539.

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Lake formation and drainage are pervasive phenomena in permafrost regions. Drained lake basins (DLBs) are often the most common landforms in lowland permafrost regions in the Arctic (50% to 75% of the landscape). However, detailed assessments of DLB distribution and abundance are limited. In this study, we present a novel and scalable remote sensing-based approach to identifying DLBs in lowland permafrost regions, using the North Slope of Alaska as a case study. We validated this first North Slope-wide DLB data product against several previously published sub-regional scale datasets and manually classified points. The study area covered >71,000 km2, including a >39,000 km2 area not previously covered in existing DLB datasets. Our approach used Landsat-8 multispectral imagery and ArcticDEM data to derive a pixel-by-pixel statistical assessment of likelihood of DLB occurrence in sub-regions with different permafrost and periglacial landscape conditions, as well as to quantify aerial coverage of DLBs on the North Slope of Alaska. The results were consistent with previously published regional DLB datasets (up to 87% agreement) and showed high agreement with manually classified random points (64.4–95.5% for DLB and 83.2–95.4% for non-DLB areas). Validation of the remote sensing-based statistical approach on the North Slope of Alaska indicated that it may be possible to extend this methodology to conduct a comprehensive assessment of DLBs in pan-Arctic lowland permafrost regions. Better resolution of the spatial distribution of DLBs in lowland permafrost regions is important for quantitative studies on landscape diversity, wildlife habitat, permafrost, hydrology, geotechnical conditions, and high-latitude carbon cycling.

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Michel, R. F. M., C. E. G. R. Schaefer, F. M. B. Simas, M. R. Francelino, E. I. Fernandes-Filho, G. B. Lyra, and J. G. Bockheim. "Active-layer thermal monitoring on the Fildes Peninsula, King George Island, maritime Antarctica." Solid Earth 5, no. 2 (December 21, 2014): 1361–74. http://dx.doi.org/10.5194/se-5-1361-2014.

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Abstract. International attention to climate change phenomena has grown in the last decade; the active layer and permafrost are of great importance in understanding processes and future trends due to their role in energy flux regulation. The objective of this paper is to present active-layer temperature data for one Circumpolar Active Layer Monitoring South hemisphere (CALM-S) site located on the Fildes Peninsula, King George Island, maritime Antarctica over an 57-month period (2008–2012). The monitoring site was installed during the summer of 2008 and consists of thermistors (accuracy of ±0.2 °C), arranged vertically with probes at different depths, recording data at hourly intervals in a high-capacity data logger. A series of statistical analyses was performed to describe the soil temperature time series, including a linear fit in order to identify global trends, and a series of autoregressive integrated moving average (ARIMA) models was tested in order to define the best fit for the data. The affects of weather on the thermal regime of the active layer have been identified, providing insights into the influence of climate change on permafrost. The active-layer thermal regime in the studied period was typical of periglacial environments, with extreme variation in surface during the summer resulting in frequent freeze and thaw cycles. The active-layer thickness (ALT) over the studied period shows a degree of variability related to different annual weather conditions, reaching a maximum of 117.5 cm in 2009. The ARIMA model could describe the data adequately and is an important tool for more conclusive analysis and predictions when longer data sets are available. Despite the variability when comparing temperature readings and ACT over the studied period, no trend can be identified.

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Mojski, Józef Edward. "Loess and periglacial phenomena, symposium of the inqua commission on loess: Lithology, genesis and geotechnic definitions and IGU commission for periglacial studies: Field and laboratory experimentation. Normandy-Jersey-Brittany, Caen, August 1986, edited by Márton Pécsi and Hugh M. French. distributors: Kultura, Hungarian foreign trading co. P.O.B. 149 1389 Budapest, Hungary. No. of pages: 311." Earth Surface Processes and Landforms 14, no. 5 (August 1989): 453. http://dx.doi.org/10.1002/esp.3290140511.

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Gärtner-Roer, Isabelle, Nina Brunner, Reynald Delaloye, Wilfried Haeberli, Andreas Kääb, and Patrick Thee. "Glacier–permafrost relations in a high-mountain environment: 5 decades of kinematic monitoring at the Gruben site, Swiss Alps." Cryosphere 16, no. 5 (May 31, 2022): 2083–101. http://dx.doi.org/10.5194/tc-16-2083-2022.

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Abstract. Digitized aerial images were used to monitor the evolution of perennially frozen debris and polythermal glacier ice at the intensely investigated Gruben site in the Swiss Alps over a period of about 50 years. The photogrammetric analysis allowed for a compilation of detailed spatio-temporal information on flow velocities and thickness changes. In addition, high-resolution GNSS (global navigation satellite system) and ground surface temperature measurements were included in the analysis to provide insight into short-term changes. Over time, extremely contrasting developments and landform responses are documented. Viscous flow within the warming and already near-temperate rock glacier permafrost continued at a constant average but seasonally variable speed of typically decimetres per year, with average surface lowering limited to centimetres to a few decimetres per year. This constant flow causes the continued advance of the characteristic convex, lava-stream-like rock glacier with its oversteepened fronts. Thawing rates of ice-rich perennially frozen ground to strong climate forcing are very low (centimetres per year) and the dynamic response strongly delayed (timescale of decades to centuries). The adjacent cold debris-covered glacier tongue remained an essentially concave landform with diffuse margins, predominantly chaotic surface structure, intermediate thickness losses (decimetres per year), and clear signs of down-wasting and decreasing flow velocity. The former contact zone between the cold glacier margin and the upper part of the rock glacier with disappearing remains of buried glacier ice embedded on top of frozen debris exhibits complex phenomena of thermokarst in massive ice and backflow towards the topographic depression produced by the retreating glacier tongue. As is typical for glaciers in the Alps, the largely debris-free glacier part shows a rapid response (timescale of years) to strong climatic forcing with spectacular retreat (>10 m a−1) and mass loss (up to >1 m w.e. specific mass loss per year). The system of periglacial lakes shows a correspondingly dynamic evolution and had to be controlled by engineering work for hazard protection.

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Brosche, Karl-Ulrich. "Wirkungen des pleistözänen kaltzeitlichen Klimas, insbesondere des Bodenfrostes, in den Sedimenten des östlichen Ostfalen (Eiskeile, Löß-Flugsand, asymmetrische Täler)." E&G Quaternary Science Journal 47, no. 1 (January 1, 1997): 89–106. http://dx.doi.org/10.3285/eg.47.1.05.

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Abstract. In the second part of the article with the title "Wirkungen des ..." a various documentation of pictures is presented to analyse the ice-wedge casts of the eastern part of Lower Saxony (Ostfalen). These structures are the only periglacial phenomena, which represent doublessly a former permafrost soil. After a short introduction, in chapter 2 Saalian or probably older nets of ice-wedge casts are documentated, which reach in a depth of 6 m in Ahlum (east of Wolfenbüttel) and which can be dated very well using their content of sediments and their cover sediments. In Barmke (nr. 12, fig. 1) there were found normal ice-wedge casts and former ice-vains and "Eisgänge" (fig. 2), which posess a Saalian or older age. - The ice-wedge casts with a length of 2,0 to 2,5 m, which were formed in one continuing phase are all of Weichselian age. - In some exemples polygenetic ice-wedge casts could b e found, which grew either during the Saalian (or the Elsterian) or - in other examples - during the Saalian and Weichselian time. - In chapter 5 some „Kleinkeile" and „Kissenböden" with little syngenetic frost fissures are presented, which are not due to a permafrost soil, but are formed by a frost soil during a stadial or interstadial phase within the Weichselian (fig. 14 and 15). - A sequence of a yellow loess in alternation with sand layers from the Eocene formation, which was a great exception, was presented from the northern loess border (fig. 16). - Only two climatic asymmetric valleys could be found, which were developed since the Saalian ice left our landscape. - All described forms were developed in sediments of the Quaternary or in sands and clay of the Tertiary. Only some ice-wedge casts were formed in marls and clay of the Keuper. - Syngenetic cryoturbation forms and ice-wedge casts could only b e found in the Oker-Mittelterrasse (fig. 18). - Climatic conclusions for the coldest times of the Weichselian and Saalian time were made: at least a temperature depression of 14 to 15° could be found.

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Knizhnikov, Yu F., V. I. Kravtsova, and I. A. Labutina. "Cartographic Remote-Sensing Monitoring of Glaciological Systems (Example, Mount El‛ Brus, U.S.S.R.) (Abstract)." Annals of Glaciology 9 (1987): 247–48. http://dx.doi.org/10.3189/s0260305500000872.

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Remote-sensing methods in monitoring the glacierization of Mount EI‛ brus are used to produce base and dynamic maps, and to obtain quantitative information (dynamic indices) about the rate, intensity, and variations of the process. The monitoring system is divided, according to scope and territory covered, into small-scale for total glacierization and the periglacial zone, medium-scale for separate glaciers, and large-scale (detailed) for part of the glaciers or sectors of the adjoining slopes. The approximate relationship of even scales is 1 : 4.Small-scale monitoring remote-sensing systems are important for making maps showing the complex characteristics of the glaciological system. A series of maps was produced including geographical, those of high-altitude zones, slope and exposure angles, geological, glaciomorphological, climatic (temperature, precipitation, and winds), distribution of direct solar radiation, hydrological (source of streams), seats of avalanches, and landslides. All these data serve as a cartographical basis in monitoring the glacierization of Mount EI‛ brus. They are compiled from remotely sensed and Earth-based data.Current monitoring on a small scale includes observations of the conditions which determine the existence of the glacial system - this includes data on winter snowfall and the period of snow cover. These observations were obtained from meteorological and resource satellites, and from scanner data of medium and high resolution. Also important are observations of changes in the outline of glaciers, times of snowfall and character of the distribution of snow, and its redistribution due to avalanches and snowstorms. High-resolution space photographs, small-scale aerial photographs, and aerovisual observations provide the data for these observations. It has been determined that the area of the glaciers of Mount El‛ brus has been reduced by 1 % in the last 25 years, i.e. the rate of its deglacierization dropped sharply as compared to preceding decades.The role of quantitative information gains importance in the medium-scale level of monitoring. Topographical maps of separate glaciers compiled from aerial photographs or data from ground stereo-photogrammetric surveys constitute the base maps at this level. The main method used in monitoring were large-scale surveys from aircraft, perspective surveys from helicopters, and phototheodolite surveys. Multi-date surveys of the glaciers provide data about the changes in their outlines and height, the character of their relief, their moraines, the amount of snow accumulation and ablation in separate years, the surface rates of ice flow and their fluctuations. The techniques by which quantitative information is obtained about changes in the glaciers are derived from processing the data of multi-date surveys. The organization and techniques of phototheodolite surveys have been improved. A theory evolved for determining the surface-ice movement by stereo-photogrammetric means and the technique for it has also improved; algorithms and programs for machine processing of the data of multi-date surveys (ground and from aircraft) have been producedAt this level of monitoring, it has been found that the retreat rate of most glaciers has slowed down and several glaciers are now in equilibrium. Several glaciers became active at the beginning of the 1970s and 1980s; this was accompanied by an increase in their height and forward movement. For example, activation of Kyukyurtlyu Glacier has been recorded (higher surface and increasing flow rate) which has caused the glacier to move forward 100 m. Surveys at an interval of 2 years recorded the beginning of the process of retreat of this glacier.Detailed monitoring is used to detect the mechanism of the dynamic processes and to study it on local representative sectors. On a glacier it may take the form of annual surveys of its tongue, which makes it possible to observe the processes of formation of moraines and glacio-fluvial relief. Studies may also be made of the mechanism of the movement of avalanches and landslides, deducing their quantitative characteristics and appraising the results of avalanches and landslides. Multi-date surveys of sectors of the slopes provide information about processes in the periglacial zone. At this level, regularly repeated ground stereo-photogrammetric surveys are the main means of observation.Glaciological remote-sensing monitoring provides a wealth of data for theoretical development in the field of glaciology. It makes it possible to forecast and produce warnings about hazardous processes and phenomena.

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Knizhnikov, Yu F., V. I. Kravtsova, and I. A. Labutina. "Cartographic Remote-Sensing Monitoring of Glaciological Systems (Example, Mount El‛ Brus, U.S.S.R.) (Abstract)." Annals of Glaciology 9 (1987): 247–48. http://dx.doi.org/10.1017/s0260305500000872.

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Remote-sensing methods in monitoring the glacierization of Mount EI‛ brus are used to produce base and dynamic maps, and to obtain quantitative information (dynamic indices) about the rate, intensity, and variations of the process. The monitoring system is divided, according to scope and territory covered, into small-scale for total glacierization and the periglacial zone, medium-scale for separate glaciers, and large-scale (detailed) for part of the glaciers or sectors of the adjoining slopes. The approximate relationship of even scales is 1 : 4. Small-scale monitoring remote-sensing systems are important for making maps showing the complex characteristics of the glaciological system. A series of maps was produced including geographical, those of high-altitude zones, slope and exposure angles, geological, glaciomorphological, climatic (temperature, precipitation, and winds), distribution of direct solar radiation, hydrological (source of streams), seats of avalanches, and landslides. All these data serve as a cartographical basis in monitoring the glacierization of Mount EI‛ brus. They are compiled from remotely sensed and Earth-based data. Current monitoring on a small scale includes observations of the conditions which determine the existence of the glacial system - this includes data on winter snowfall and the period of snow cover. These observations were obtained from meteorological and resource satellites, and from scanner data of medium and high resolution. Also important are observations of changes in the outline of glaciers, times of snowfall and character of the distribution of snow, and its redistribution due to avalanches and snowstorms. High-resolution space photographs, small-scale aerial photographs, and aerovisual observations provide the data for these observations. It has been determined that the area of the glaciers of Mount El‛ brus has been reduced by 1 % in the last 25 years, i.e. the rate of its deglacierization dropped sharply as compared to preceding decades. The role of quantitative information gains importance in the medium-scale level of monitoring. Topographical maps of separate glaciers compiled from aerial photographs or data from ground stereo-photogrammetric surveys constitute the base maps at this level. The main method used in monitoring were large-scale surveys from aircraft, perspective surveys from helicopters, and phototheodolite surveys. Multi-date surveys of the glaciers provide data about the changes in their outlines and height, the character of their relief, their moraines, the amount of snow accumulation and ablation in separate years, the surface rates of ice flow and their fluctuations. The techniques by which quantitative information is obtained about changes in the glaciers are derived from processing the data of multi-date surveys. The organization and techniques of phototheodolite surveys have been improved. A theory evolved for determining the surface-ice movement by stereo-photogrammetric means and the technique for it has also improved; algorithms and programs for machine processing of the data of multi-date surveys (ground and from aircraft) have been produced At this level of monitoring, it has been found that the retreat rate of most glaciers has slowed down and several glaciers are now in equilibrium. Several glaciers became active at the beginning of the 1970s and 1980s; this was accompanied by an increase in their height and forward movement. For example, activation of Kyukyurtlyu Glacier has been recorded (higher surface and increasing flow rate) which has caused the glacier to move forward 100 m. Surveys at an interval of 2 years recorded the beginning of the process of retreat of this glacier. Detailed monitoring is used to detect the mechanism of the dynamic processes and to study it on local representative sectors. On a glacier it may take the form of annual surveys of its tongue, which makes it possible to observe the processes of formation of moraines and glacio-fluvial relief. Studies may also be made of the mechanism of the movement of avalanches and landslides, deducing their quantitative characteristics and appraising the results of avalanches and landslides. Multi-date surveys of sectors of the slopes provide information about processes in the periglacial zone. At this level, regularly repeated ground stereo-photogrammetric surveys are the main means of observation. Glaciological remote-sensing monitoring provides a wealth of data for theoretical development in the field of glaciology. It makes it possible to forecast and produce warnings about hazardous processes and phenomena.

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НАМЗАЛОВ, Б. Ц. Б., А. М. САМДАН, Л. В. БУДАЖАПОВ, and М. Б. Ц. НАМЗАЛОВ. "FEATURES OF SPATIAL STRUCTURE AND CENOGENESIS RELICT LARCH FORESTS OF THE MOUNTAIN FOREST-STEPPE OF SOUTHERN SIBERIA." Сибирский лесной журнал, no. 1 (February 29, 2024): 3–12. http://dx.doi.org/10.15372/sjfs20240101.

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Приведены оригинальные сведения о реликтовых явлениях в структуре лесного компонента горной лесостепи Южной Сибири (ЮС). Лиственничные (лиственница сибирская ( Larix sibirica Ledeb.)) кустарниково-травяные леса - характерный элемент растительности лесостепи ЮС, из них древнейшими считаются плиоценовые, наиболее термофильные, аналоги современной лесостепи, отмеченные в предгорьях хр. Западный Танну-Ола (урочище Хорлеты) - лиственничник мелколистножимолостно-гмелинополынный с участием в составе сообщества нагорно-азиатских элементов Древнего Средиземья. Важно отметить, что в видовом составе реликтового лиственничника роль характерных бореальных видов, таких как спирея средняя ( Spiraea media Schmidt), шиповник иглистый ( Rosa acicularis Lindl.), незначительна в сравнении с типичными элементами семиаридных флороценотипов Древнего Средземья. Среди них особенно значимо в филогенетическом отношении участие в составе кустарникового яруса сообщества жимолости мелколистной - элемента алтае-джунгаро-тянь-шанского реликтового флороценотипа нагорно-азитских кустарников. В условиях Западного Забайкалья, в отрогах хр. Малый Хамар-Дабан (урочище Инзагатуй), описан реликтовый лиственничник стоповидноосоково-сибирскочиевый с участием характерных видов перигляциального комплекса плейстоцена. В четвертичном периоде, особенно в ксеротермические фазы голоцена, по мере дегляциации горных ледников и становления относительно теплого и умеренного климата создаются условия для формирования современной горной лесостепи в условиях семигумидного климатического режима ЮС. Эталонным является лиственничник разнотравно-ирисово-осоковый, отличающийся богатством видового состава травянистых растений наряду с хорошо развитым подлеском. Это выражается в процессах мезоксерофитизации растительности с развитием флористических комплексов луговых степей и гемибореальных лесов в структуре фитоценокомплексов горной экспозиционной лесостепи от Алтая до Забайкалья. The article provides original information about relict phenomena in the structure of the forest component of the mountain forest-steppe of Southern Siberia (SS). Larch (Siberian larch ( Larix sibirica Ledeb.)) shrub-grass forests are characteristic element of vegetation in the forest-steppe of the SS. The oldest are the Pliocene, the most thermophilic analogues of the modern forest-steppe, noted in the foothills of the Western Tannu-Ola ridge (Horlety) is a small-leaved larch, dwarf-gmelin wormwood with participation in the community of mountain-Asian elements of ancient Middle-earth. It is important to note that in the species composition of the relict larch forest, the role of characteristic boreal species such as spirea ( Spiraea media Schmidt), prickly wild rose ( Rosa acicularis Lindl.) is insignificant in comparison with typical elements of semiarid florocenotypes of the Ancient Middle Earth. Among them, participation in the shrub layer of the small-leaved honeysuckle community, an element of the Altai-Dzhungar-Tien Shan relict florocenotype of highland Asian shrubs, is especially significant in phylogenetic terms. In the conditions of Western Transbaikalia, in the spurs of the ridge Malyi Khamar-Daban (Inzagatuy tract) describes the relict larch forest with the participation of characteristic species of the periglacial Pleistocene complex. In the Quaternary period - especially the xerothermic phases of the Holocene, as mountains deglaciate and a relatively warm and temperate climate develops, conditions are created for the formation of a modern mountain forest-steppe in the conditions of the semi-humid climatic regime of the SS. For example, forb-iris-sedge larch, characterized by a rich species composition of herbaceous plants, along with a well-developed undergrowth. This is expressed in the processes of mesoxerophytization of vegetation with the development of floristic complexes of meadow steppes and hemiboreal forests in the structure of phytocoenocomplexes of mountain exposure forest-steppe from Altai to Transbaikalia.

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Бондырев, И. В. "PERIGLACIAL PROCESSES AND PHENOMENA." Геология и геофизика Юга России, no. 2 (June 19, 2015). http://dx.doi.org/10.23671/vnc.2015.2.55269.

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Mokrik, R., and V. Samalavičius. "Interpretation of the anomalous groundwater chemistry and 234u/238u activity ratio disequilibrium in the northern part of the baltic region." Lithuanian Journal of Physics 62, no. 1 (January 17, 2022). http://dx.doi.org/10.3952/physics.v62i1.4645.

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The anomalous isotope-hydrogeochemistry phenomena in the groundwater of Estonian Cambrian-Vendian (Ediacaran) and Ordovician-Cambrian aquifer systems were formed in the Late-Middle Pleistocene. In the periglacial environment, in northern and northwestern Estonia, these aquifer systems with fracture porose crystalline basement are connected to hydraulically joint unit characterized by high radioactivity groundwater. A significant alteration of groundwater occurred by series of isotope and chemistry facies fractionation. In this study, uranium isotopes activity ratio (234U/238U), 4He content, isotope-hydrogeochemistry and adjusted 14C ages are coupled for a new prospect of the estimation of northern Baltic Basin groundwater evolution. Analyzing radiocarbon and 4He groundwater residence time results and uranium isotope activity ratio distribution suggests a prolonged periglacial environment in which groundwater evolved. Stable isotope ratios of δ18O and δ2H correlation and hydrochemical composition changes support the cryogenic origin of groundwater. Pleistocene glaciations cyclically affect groundwater in multiple ways: permafrost isotope-geochemistry partitioning; periodically changing reversed flow directions of recharge and discharge areas; oscillations of the sea, river system, and periglacial lakes level, surface and sub-permafrost water mixing via taliks and fractured basement rocks. These processes lead to forming the sequence of isotope-hydrogeochemistry types and specific zoning; in general, two separate groundwater fractions – brackish in the lower part and freshened above. An extensive groundwater exploitation on the northern coast sites influenced a sharp dysfunction in the groundwater body, destabilizing the natural equilibrium state formed in the Holocene and Pleistocene.

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50

Ferreira, António Brum. "Considerações acerca do arrefecimento Plistocénico em Portugal." Finisterra 35, no. 70 (December 13, 2012). http://dx.doi.org/10.18055/finis1660.

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NOTE ON THE PLEISTOCENE COOLING IN PORTUGAL – Prevailing conditionsin the North Atlantic and Western Europe during the Maximum Cooling of the Last Glaciation can be deduced from the Climap Project (1976) results and from the Atlas of Paleoclimates and Paleoenvironments of the Northern Hemisphere (FRENZEL et al., 1992). Taking into account this framework of extreme climatic conditions and the nature of the glacial and periglacial relict phenomena in the Iberian Peninsula, an attempt is made to evaluate the degree of cooling in Portugal during the Gerês and Estrela glaciations. A drop of about 10º C in summer temperatures is suggested.

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Journal articles on the topic 'Periglacial phenomena'

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