Pluvial Hypothesis
In geology and climatology, a pluvial is either a modern climate characterized by relatively high precipitation or an interval of time of variable length, decades to thousands of years, during which a climate is characterized by relatively high precipitation or humidity, Subdivisions of a pluvial, which are characterized by relatively high precipitation, are known as a subpluvials. Formally, pluvials were equated with glacial stages of the Quaternary. However, pluvials, as in equatorial regions, can also occur during interglacial stages. Lower latitudes have even experienced major pluvials in early to mid-Holocene times. In geomorphology, a pluvial refers to a geologic episode, change, process, deposit, or feature that is the result of the action or effects of rain. Sometimes, it also refers to the fluvial action of rainwater flowing in a stream channel, including a flood, known as a pluvial flood, that is the direct result of excessive precipitation.Bradley, R.S. (2015) ''Paleo ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Cope
The cope (known in Latin as ''pluviale'' 'rain coat' or ''cappa'' 'cape') is a liturgical vestment, more precisely a long mantle or cloak, open in front and fastened at the breast with a band or clasp. It may be of any liturgical colours, liturgical colour. A cope may be worn by any rank of the clergy. If worn by a bishop, it is generally accompanied by a mitre. The buckle, clasp, which is often highly ornamented, is called a ''morse''. In art, angels are often shown wearing copes, especially in Early Netherlandish painting. History There has been little change in the character of the vestment from the earliest ages. Then as now it was made of a piece of silk or other cloth of semicircular shape, which distinguished it from the earlier form of chasuble, as a chasuble had straight edges sewn together in front. Both are similar in form and origin to the Orthodox phelonion. The only noticeable modification which the cope has undergone lies in the disappearance of the hood. So ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Fluvial
In geography and geology, fluvial processes are associated with rivers and streams and the deposits and landforms created by them. When the stream or rivers are associated with glaciers, ice sheets, or ice caps, the term glaciofluvial or fluvioglacial is used. Fluvial processes Fluvial processes include the motion of sediment and erosion or deposition on the river bed. The movement of water across the stream bed exerts a shear stress directly onto the bed. If the cohesive strength of the substrate is lower than the shear exerted, or the bed is composed of loose sediment which can be mobilized by such stresses, then the bed will be lowered purely by clearwater flow. In addition, if the river carries significant quantities of sediment, this material can act as tools to enhance wear of the bed ( abrasion). At the same time the fragments themselves are ground down, becoming smaller and more rounded (attrition). Sediment in rivers is transported as either bedload (the coarser fr ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Climatology
Climatology (from Greek , ''klima'', "place, zone"; and , '' -logia'') or climate science is the scientific study of Earth's climate, typically defined as weather conditions averaged over a period of at least 30 years. This modern field of study is regarded as a branch of the atmospheric sciences and a subfield of physical geography, which is one of the Earth sciences. Climatology now includes aspects of oceanography and biogeochemistry. The main methods employed by climatologists are the analysis of observations and modelling of the physical processes that determine the climate. The main topics of research are the study of climate variability, mechanisms of climate changes and modern climate change. Basic knowledge of climate can be used within shorter term weather forecasting, for instance about climatic cycles such as the El Niño–Southern Oscillation (ENSO), the Madden–Julian oscillation (MJO), the North Atlantic oscillation (NAO), the Arctic oscillation (AO), the Pac ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Pluvial Lake
A pluvial lake is a body of water that accumulated in a basin because of a greater moisture availability resulting from changes in temperature and/or precipitation. These intervals of greater moisture availability are not always contemporaneous with glacial periods. Pluvial lakes are typically closed lakes that occupied endorheic basins. Pluvial lakes that have since evaporated and dried out may also be referred to as ''paleolakes''.Goudie, A.S., 2013. ''and semi-arid geomorphology.'' Cambridge University Press. Etymology The word comes from the Latin ''pluvia'', which means "rain". Geology Pluvial lakes represent changes in the hydrological cycle: wet cycles generate large lakes, and dry cycles cause the lakes to recede. Accumulated sediments show the variation in water level. During glacial periods, when the lake level is fairly high, mud sediments will settle out and be deposited. At times in between glaciers (interglacial), salt deposits may be present because of the ari ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Neolithic Subpluvial
The African humid period (AHP) (also known by other names) is a climate period in Africa during the late Pleistocene and Holocene geologic epochs, when northern Africa was wetter than today. The covering of much of the Sahara desert by grasses, trees and lakes was caused by changes in Earth's orbit around the Sun; changes in vegetation and dust in the Sahara which strengthened the African monsoon; and increased greenhouse gases. During the preceding Last Glacial Maximum, the Sahara contained extensive dune fields and was mostly uninhabited. It was much larger than today, but its lakes and rivers such as Lake Victoria and the White Nile were either dry or at low levels. The humid period began about 14,600–14,500 years ago at the end of Heinrich event 1, simultaneously to the Bølling–Allerød warming. Rivers and lakes such as Lake Chad formed or expanded, glaciers grew on Mount Kilimanjaro and the Sahara retreated. Two major dry fluctuations occurred; during the Younger Drya ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Mousterian Pluvial
The Mousterian Pluvial is a mostly obsolete term for a prehistoric wet and rainy (pluvial) period in North Africa. It was described as beginning around 50,000 years before the present ( BP), lasting roughly 20,000 years, and ending ca. 30,000 BP. In Africa, the Mousterian industry was an archaeological term for a category of Middle Stone Age (or Middle Paleolithic) stone tool production. During the time that archaeological dates were determined by radiocarbon decay, the production of such tools was once thought to have occurred just before the limit of radiocarbon dating at 40,000 to 35,000 BP. In Europe, Mousterian tools were made by archaic Neanderthals. In Africa, such tools were made by early anatomically-modern ''Homo sapiens''. Similar people also made similar tools which are categorized as Alterian. To avoid confusion about their makers, the Mousterian and Alterian tools are now sometimes grouped as Aterian. With more recent dating methods, the tools are now understood to ha ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Carnian Pluvial Event
The Carnian pluvial episode (CPE), often called the Carnian pluvial event, was an interval of major change in global climate synchronous with significant changes in Earth's biota both in the sea and on land. It occurred during the latter part of the Carnian Stage of the late Triassic period over an interval of perhaps 1-2 million years (approximately 234-232 million years ago), across the boundary between the Julian and Tuvalian substages of the Carnian. It represents a significant episode in the evolution and diversification of many taxa that are important today, among them some of the earliest dinosaurs (which include the ancestors of birds), lepidosaurs (ancestors of modern-day snakes and lizards), pterosaurs and true mammals. In the marine realm it saw the first appearance among the microplankton of coccoliths and dinoflagellates , with the latter linked to the rapid diversification of scleractinian corals through the establishment of symbiotic zooxanthellae. The CPE also saw ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Abbassia Pluvial
The Abbassia Pluvial was an extended wet and rainy period in the climate history of North Africa, lasting from c. 120,000 to 90,000 years ago. As such it spans the transitional period connecting the Lower and Middle Paleolithic. As with the subsequent Mousterian Pluvial (c. 50,000 to 30,000 years ago), the Abbassia Pluvial brought wet and fertile conditions to what is now the Sahara Desert, which bloomed with lush vegetation fed by lakes, swamps, and river systems, many of which later disappeared in the drier climate that followed the pluvial. African wildlife that is now associated with the grasslands and woodlands south of the Sahara penetrated the entire North African region during the Abbassia Pluvial. Stone Age cultures (notably the Mousterian and the Aterian industries) flourished in North Africa during the Abbassia Pluvial. The shift to harsher climate conditions that came with the end of the pluvial may have promoted the emigration of modern ''Homo sapiens'' out of Afr ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Geomorphology
Geomorphology (from Ancient Greek: , ', "earth"; , ', "form"; and , ', "study") is the scientific study of the origin and evolution of topographic and bathymetric features created by physical, chemical or biological processes operating at or near Earth's surface. Geomorphologists seek to understand why landscapes look the way they do, to understand landform and terrain history and dynamics and to predict changes through a combination of field observations, physical experiments and numerical modeling. Geomorphologists work within disciplines such as physical geography, geology, geodesy, engineering geology, archaeology, climatology, and geotechnical engineering. This broad base of interests contributes to many research styles and interests within the field. Overview Earth's surface is modified by a combination of surface processes that shape landscapes, and geologic processes that cause tectonic uplift and subsidence, and shape the coastal geography. Surface processes co ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Geology
Geology () is a branch of natural science concerned with Earth and other astronomical objects, the features or rocks of which it is composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology, and so is treated as one major aspect of integrated Earth system science and planetary science. Geology describes the structure of the Earth on and beneath its surface, and the processes that have shaped that structure. It also provides tools to determine the relative and absolute ages of rocks found in a given location, and also to describe the histories of those rocks. By combining these tools, geologists are able to chronicle the geological history of the Earth as a whole, and also to demonstrate the age of the Earth. Geology provides the primary evidence for plate tectonics, the evolutionary history of life, and the Earth's past climates. Geologists broadly study the properties and processes of E ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Holocene
The Holocene ( ) is the current geological epoch. It began approximately 11,650 cal years Before Present (), after the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene together form the Quaternary period. The Holocene has been identified with the current warm period, known as MIS 1. It is considered by some to be an interglacial period within the Pleistocene Epoch, called the Flandrian interglacial.Oxford University Press – Why Geography Matters: More Than Ever (book) – "Holocene Humanity" section https://books.google.com/books?id=7P0_sWIcBNsC The Holocene corresponds with the rapid proliferation, growth and impacts of the human species worldwide, including all of its written history, technological revolutions, development of major civilizations, and overall significant transition towards urban living in the present. The human impact on modern-era Earth and its ecosystems may be considered of global si ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Interglacial
An interglacial period (or alternatively interglacial, interglaciation) is a geological interval of warmer global average temperature lasting thousands of years that separates consecutive glacial periods within an ice age. The current Holocene interglacial began at the end of the Pleistocene, about 11,700 years ago. Pleistocene During the 2.5 million years of the Pleistocene, numerous glacials, or significant advances of continental ice sheets, in North America and Europe, occurred at intervals of approximately 40,000 to 100,000 years. The long glacial periods were separated by more temperate and shorter interglacials. During interglacials, such as the present one, the climate warms and the tundra recedes polewards following the ice sheets. Forests return to areas that once supported tundra vegetation. Interglacials are identified on land or in shallow epicontinental seas by their paleontology. Floral and faunal remains of species pointing to temperate climate and indicating a s ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |