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Periglacial
Periglaciation (adjective: "periglacial", also referring to places at the edges of glacial areas) describes geomorphic processes that result from seasonal thawing of snow in areas of permafrost, the runoff from which refreezes in ice wedges and other structures. "Periglacial" suggests an environment located on the margin of past glaciers. However, freeze and thaw cycles influence landscapes outside areas of past glaciation. Therefore, periglacial environments are anywhere that freezing and thawing modify the landscape in a significant manner. Tundra is a common ecological community in periglacial areas. History Periglaciation became a distinct subject within the study of geology after Walery Łoziński, a Polish geologist, introduced the term in 1909. Łoziński drew upon the early work of Johan Gunnar Andersson. According to Alfred Jahn, his introduction of his work at the 1910 International Geological Congress held in Stockholm caused significant discussion. In the field trip ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jan Dylik
Jan Dylik (19 June 1905 – 6 June 1973) was a Polish geography professor at the University of Łódz. He was born in Łódź on 19 June 1905. In 1925 he begain post-secondary studies at Jagiellonian University. He then went on to attend Adam Mickiewicz University in Poznań to pursue research and a doctoral degree. He found himself fascinated by the differences in geology between the Greater Poland Voivodeship and the Łódź Voivodeship. He collaborated with Stanisław Lencewicz on a project to analyze the Łódź region's geology and geomorphology. The resulting paper was published in 1927, and for many years was considered the only source of information on the geology of Łódź.Profesor Jan Dylik. Sylwetki łódzkich uczonych, z. 21, red. H. Klatkowa. ŁTN, Łódź 1995, s. 29-30. From 1928-1930, while still balancing the responsibilities of research, he worked as an assistant in the National Museum of Archaeology in Poland. In 1930, he completed his doctoral degree for a d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solifluction
Solifluction is a collective name for gradual processes in which a mass moves down a slope ("mass wasting") related to freeze-thaw activity. This is the standard modern meaning of solifluction, which differs from the original meaning given to it by Johan Gunnar Andersson in 1906. Origin and evolution of the concept In the original sense it meant the movement of waste saturated in water found in periglacial regions. However it was later discovered that various slow waste movements in periglacial regions did not require saturation in water, but were rather associated to freeze-thaw processes. The term solifluction was appropriated to refer to these slow processes, and therefore excludes rapid periglacial movements. In slow periglacial solifluction there are not clear gliding planes, and therefore skinflows and active layer detachments are not included in the concept. On the other hand, movement of waste saturated in water can occur in any humid climate, and therefore this kind of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permafrost
Permafrost is ground that continuously remains below 0 °C (32 °F) for two or more years, located on land or under the ocean. Most common in the Northern Hemisphere, around 15% of the Northern Hemisphere or 11% of the global surface is underlain by permafrost, with the total area of around 18 million km2. This includes substantial areas of Alaska, Greenland, Canada and Siberia. It can also be located on mountaintops in the Southern Hemisphere and beneath ice-free areas in the Antarctic. Permafrost does not have to be the first layer that is on the ground. It can be from an inch to several miles deep under the Earth's surface. It frequently occurs in ground ice, but it can also be present in non-porous bedrock. Permafrost is formed from ice holding various types of soil, sand, and rock in combination. Permafrost contains large amounts of biomass and decomposed biomass that has been stored as methane and carbon dioxide, making tundra soil a carbon sink. As global war ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biuletyn Peryglacjalny
''Biuletyn Peryglacjalny'' was a scientific journal covering research on periglacial geomorphology. It was established in 1954 in Łódź by Polish geomorphologist Jan Dylik, who was its editor-in-chief An editor-in-chief (EIC), also known as lead editor or chief editor, is a publication's editorial leader who has final responsibility for its operations and policies. The highest-ranking editor of a publication may also be titled editor, managing ... until 1972. The journal ceased publication after 39 issues in 2000, after having played an important role in the development of periglacial geomorphology. References 1954 establishments in Poland Earth and atmospheric sciences journals Geomorphology journals Defunct journals Publications established in 1954 Publications disestablished in 2000 Multilingual journals Annual journals {{Geomorphology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climatic Geomorphology
Climatic geomorphology is the study of the role of climate in shaping landforms and the earth-surface processes. An approach used in climatic geomorphology is to study relict landforms to infer ancient climates. Being often concerned about past climates climatic geomorphology considered sometimes to be an aspect of historical geology. Since landscape features in one region might have evolved under climates different from those of the present, studying climatically disparate regions might help understand present-day landscapes. For example, Julius Büdel studied both cold-climate processes in Svalbard and weathering processes in tropical India to understand the origin of the relief of Central Europe, which he argued was a palimpsest of landforms formed at different times and under different climates. Sub-disciplines The various subbranches of climatic geomorphology focus on specific climatic environments. Desert geomorphology Desert geomorphology or the geomorphology of arid an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Wedge
An ice wedge is a crack in the ground formed by a narrow or thin piece of ice that measures up to 3–4 meters in length at ground level and extends downwards into the ground up to several meters. During the winter months, the water in the ground freezes and expands. Once temperatures reach −17 degrees Celsius or lower, the ice that has already formed acts like a solid and expands to form cracks in the surface known as ice wedges. As this process continues over many years ice wedges can grow, up to the size of a swimming pool. Ice wedges usually appear in a polygonal pattern known as ice wedge polygons. The cracks can also be filled with materials other than ice, especially sand, and are then called sand wedges. Formation There are many theories that attempt to explain the origin of ice wedges but only one has been consistently supported by most prominent scientists: the thermal contraction theory. Thermal contraction theory The thermal contraction theory posits that during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walery Łoziński
Walery Władysław Daniel Łoziński (1880–1944) was a Polish geographer, geomorphologist and soil scientist known for introducing the concept of periglaciation into geomorphology in 1909. Łoziński extended the work of Swedish geologist Johan Gunnar Andersson who had written about periglacial phenomena in Bjørnøya and the Falkland Islands. The concept of "periglaciation" was the subject of an intensive discussion at the 1910 International Geological Congress The International Union of Geological Sciences (IUGS) is an international non-governmental organization devoted to international cooperation in the field of geology. About The IUGS was founded in 1961 and is a Scientific Union member of the Inte ... held in Stockholm. References Polish geomorphologists Polish soil scientists 1880 births 1944 deaths Polish geographers Scientists from Lviv University of Lviv alumni Jagiellonian University faculty Burials at Rakowicki Cemetery {{scientist-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tundra
In physical geography, tundra () is a type of biome where tree growth is hindered by frigid temperatures and short growing seasons. The term ''tundra'' comes through Russian (') from the Kildin Sámi word (') meaning "uplands", "treeless mountain tract". There are three regions and associated types of tundra: Arctic tundra, alpine tundra, and Antarctic tundra. Tundra vegetation is composed of dwarf shrubs, sedges, grasses, mosses, and lichens. Scattered trees grow in some tundra regions. The ecotone (or ecological boundary region) between the tundra and the forest is known as the tree line or timberline. The tundra soil is rich in nitrogen and phosphorus. The soil also contains large amounts of biomass and decomposed biomass that has been stored as methane and carbon dioxide in the permafrost, making the tundra soil a carbon sink. As global warming heats the ecosystem and causes soil thawing, the permafrost carbon cycle accelerates and releases much of these soil-contained g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Johan Gunnar Andersson
Johan Gunnar Andersson (3 July 1874 – 29 October 1960)"Andersson, Johan Gunnar" in ''Encyclopædia Britannica, The New Encyclopædia Britannica''. Chicago: Encyclopædia Britannica Inc., 15th edn., 1992, Vol. 1, p. 385. was a Sweden, Swedish archaeologist, paleontologist and geologist, closely associated with the beginnings of China, Chinese archaeology in the 1920s. Early life and polar research After studies at Uppsala University, and research in the polar regions, Andersson served as Director of Geological Survey of Sweden, Sweden's National Geological Survey. He participated in the Swedish Antarctic Expedition of 1901 to 1903 (on the ship ''Antarctic (ship), Antarctic''). His work on the Falkland Islands and the Bear Island (Norway), Bjørnøya, where he first coined the term solifluction, influenced Walery Łoziński create the concept of periglaciation in 1909. Chinese archaeology In 1914, Andersson was invited to China as mining adviser to the Chinese government. His af ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carl Troll
Carl Troll (24 December 1899 in Gabersee – 21 July 1975 in Bonn), was a German geographer, brother of botanist Wilhelm Troll. From 1919 until 1922 Troll studied biology, chemistry, geology, geography and physics at the Universität in München. In 1921 he obtained his doctorate in botany and in 1925 his habilitation in geography. Between 1922 and 1927 he worked as an assistant at the Geography Institute in Munich. Troll was engaged in research in the ecology and geography of mountainous lands: between 1926 and 1929 went on a research journey throughout South American Andean countries where he visited northern Chile, Bolivia, Peru, Ecuador, Colombia, and Panama. In 1933 and 1934 his research interests took him to East and South Africa; in 1937 Troll was in Ethiopia; and in 1954 he visited Mexico. In 1930 he became professor of colonial and overseas geography in Berlin, and in 1938 professor of geography in Bonn. Troll, who utilised aerial photographs in his research, coined t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Latitude
In geography, latitude is a coordinate that specifies the north– south position of a point on the surface of the Earth or another celestial body. Latitude is given as an angle that ranges from –90° at the south pole to 90° at the north pole, with 0° at the Equator. Lines of constant latitude, or ''parallels'', run east–west as circles parallel to the equator. Latitude and ''longitude'' are used together as a coordinate pair to specify a location on the surface of the Earth. On its own, the term "latitude" normally refers to the ''geodetic latitude'' as defined below. Briefly, the geodetic latitude of a point is the angle formed between the vector perpendicular (or ''normal'') to the ellipsoidal surface from the point, and the plane of the equator. Background Two levels of abstraction are employed in the definitions of latitude and longitude. In the first step the physical surface is modeled by the geoid, a surface which approximates the mean sea level over the ocean ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
