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Pluvial
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. No lower latitudes have 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 A river is a natural stream of fresh water that flows on land or inside caves towards another body of water at a lower elevation, such as an ocean, lake, or another ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carnian Pluvial Event
The Carnian pluvial episode (CPE), often called the Carnian pluvial event, was a period of major change in global climate that coincided with significant changes in Earth's biota both in the sea and on land. It occurred during the latter part of the Carnian Stage, a subdivision of the late Triassic period, and lasted for perhaps 1–2 million years (around 234–232 million years ago). The CPE corresponds to 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 (the ancestors of modern-day snakes and lizards) and mammaliaforms (ancestors of 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 within them. The CPE also saw the extinction of many aqua ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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] |
Neolithic Subpluvial
The African humid period (AHP; also known by other names) was 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 the Earth's axial tilt, 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, and 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 Dryas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cope
A cope ( ("rain coat") or ("cape")) is a liturgical long mantle or cloak, open at the front and fastened at the breast with a band or clasp. It may be of any liturgical colour. A cope may be worn by any rank of the Catholic or Anglican clergy, and by licensed lay ministers on certain occasions. If worn by a bishop, it is generally accompanied by a mitre. The 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 cope since it was first worn by the clergy. It was made of a semicircular piece of silk or other material, its shape distinguishing it from the chasuble, which had straight edges sewn together in front. Both garments are similar in form and origin to the Orthodox phelonion. Modern copes no longer have a hood. Some early examples feature a triangular hood, which was intended to protect the head during proc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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. Terminology and definition 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 to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
African Pluvial Periods
African pluvial periods are an obsolete system of climatic periods previously used by paleontologists working in East Africa. Background The sedimentary deposits left by ancient lakes in East Africa had enabled Louis Leakey and post-war paleontologists to define major climatic periods considered wet, interspersed with drier periods. Of progressively decreasing durations, they each bore the name of the site where the first clues had been collected: Kageran ( Kagera), Kamasian, Kanjeran (Kanjera) and Gamblian. Paleontologists believed that the quasi-arid zones then became wooded savannahs where animals and prehistoric hunter-gatherers could thrive. Chronology These ancient climatic periods were only very approximately dated: * Kageran: Calabrian (Early Pleistocene) The Kageran takes its name from the Kagera River, which flows through Rwanda and northwestern Tanzania before flowing into Lake Victoria. * Kamasian: Early Middle or Central Pleistocene; the Kamasian was more or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluvial
A river is a natural stream of fresh water that flows on land or inside caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it runs out of water, or only flow during certain seasons. Rivers are regulated by the water cycle, the processes by which water moves around the Earth. Water first enters rivers through precipitation, whether from rainfall, the runoff of water down a slope, the melting of glaciers or snow, or seepage from aquifers beneath the surface of the Earth. Rivers flow in channeled watercourses and merge in confluences to form drainage basins, or catchments, areas where surface water eventually flows to a common outlet. Rivers have a great effect on the landscape around them. They may regularly overflow their banks and flood the surrounding area, spreading nutrients to the surrounding area. Sediment or alluvium carried by rivers shapes the landscape a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climatology
Climatology (from Greek , ''klima'', "slope"; 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. Climate concerns the atmospheric condition during an extended to indefinite period of time; weather is the condition of the atmosphere during a relative brief period of time. The main topics of research are the study of climate variability, mechanisms of climate changes and modern climate change. This topic of study is regarded as part of the atmospheric sciences and a subdivision of physical geography, which is one of the Earth sciences. Climatology includes some aspects of oceanography and biogeochemistry. The main methods employed by climatologists are the analysis of observations and modelling of the physical processes that determine climate. Short term weather forecasting can be interpreted in terms of knowledge of longer-term phenomena of climate, for insta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geomorphology
Geomorphology () is the scientific study of the origin and evolution of topographic and bathymetric features generated 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 comprise the action of water, wind, ice, wildfire, and lif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geology
Geology (). is a branch of natural science concerned with the Earth and other astronomical objects, the rocks of which they are composed, and the processes by which they change over time. Modern geology significantly overlaps all other Earth sciences, including hydrology. It is integrated with 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. Geologists study the mineralogical composition of rocks in order to get insight into their history of formation. Geology determines the relative ages of rocks found at a given location; geochemistry (a branch of geology) determines their absolute ages. By combining various petrological, crystallographic, and paleontological tools, geologists are able to chronicle the geological history of the Earth as a whole. One aspect is to demonstrate the age of the Earth. Geology provides evidence for plate tectonics, the ev ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Holocene
The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene together form the Quaternary period. The Holocene is an interglacial period within the ongoing Ice age, glacial cycles of the Quaternary, and is equivalent to Marine isotope stages, Marine Isotope Stage 1. The Holocene correlates with the last maximum axial tilt towards the Sun of the Earth#Axial tilt and seasons, Earth's obliquity. The Holocene corresponds with the rapid proliferation, growth, and impacts of the human species worldwide, including Recorded history, all of its written history, technological revolutions, development of major civilizations, and overall significant transition towards urban culture, urban living in the present. The human impact on modern-era Earth and its ecosystems may be considered of global significance for th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
