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Glaciers Of France
A glacier ( ) or () is a persistent body of dense ice that is constantly moving under its own weight; it forms where the accumulation of snow exceeds its ablation (melting and sublimation) over many years, often centuries. Glaciers slowly deform and flow due to stresses induced by their weight, creating crevasses, seracs, and other distinguishing features. Because glacial mass is affected by long-term climate changes, e.g., precipitation, mean temperature, and cloud cover, glacial mass changes are considered among the most sensitive indicators of climate change. There are about 198,000 to 200,000 glaciers in the world. Glaciers by continent Africa Africa, specifically East Africa, has contained glacial regions, possibly as far back as the last glacier maximum 10 to 15 thousand years ago. Seasonal snow does exist on the highest peaks of East Africa as well as in the Drakensberg Range of South Africa, the Stormberg Mountains, and the Atlas Mountains in Morocco. Currently, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conness Glacier
The Conness Glacier is on the steep northeast cirque of Mount Conness, east of the Sierra Nevada crest, in the U.S. state of California. The glacier is situated at about . and can be seen from Saddlebag Lake to the east. The glacier is the largest glacier in the Sierra Nevada north of Tioga Pass or Highway 120. See also *List of glaciers A glacier ( ) or () is a persistent body of dense ice that is constantly moving under its own weight; it forms where the accumulation of snow exceeds its ablation (melting and sublimation) over many years, often centuries. Glaciers slowly deform ... References External links and references A map of Conness Glacier Glaciers of California Glaciers of the Sierra Nevada (United States) Glaciers of Mono County, California {{US-glacier-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quaternary Glaciation
The Quaternary glaciation, also known as the Pleistocene glaciation, is an alternating series of glacial and interglacial periods during the Quaternary period that began 2.58 Ma (million years ago) and is ongoing. Although geologists describe this entire period up to the present as an "ice age", in popular culture this term usually refers to the most recent glacial period, or to the Pleistocene epoch in general. Since Earth still has polar ice sheets, geologists consider the Quaternary glaciation to be ongoing, though currently in an interglacial period. During the Quaternary glaciation, ice sheets appeared, expanding during glacial periods and contracting during interglacial periods. Since the end of the last glacial period, only the Antarctic and Greenland ice sheets have survived, with other sheets formed during glacial periods, such as the Laurentide Ice Sheet, having completely melted. The major effects of the Quaternary glaciation have been the continental erosion o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacier Morphology
Glacier morphology, or the form a glacier takes, is influenced by temperature, precipitation, topography, and other factors. The goal of glacial morphology is to gain a better understanding of glaciated landscapes and the way they are shaped. Types of glaciers can range from massive ice sheets, such as the Greenland ice sheet, to small cirque glaciers found perched on mountain tops. Glaciers can be grouped into two main categories: * Ice flow is constrained by the underlying bedrock topography * Ice flow is unrestricted by surrounding topography Unconstrained Glaciers Ice sheets and ice caps Ice sheets and ice caps cover the largest areas of land in comparison to other glaciers, and their ice is unconstrained by the underlying topography. They are the largest glacial ice formations and hold the vast majority of the world's fresh water. Ice sheets Ice sheets are the largest form of glacial formation. They are continent sized ice masses that span areas over . They are dome s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glacier
A glacier (; ) is a persistent body of dense ice that is constantly moving under its own weight. A glacier forms where the accumulation of snow exceeds its Ablation#Glaciology, ablation over many years, often Century, centuries. It acquires distinguishing features, such as Crevasse, crevasses and Serac, seracs, as it slowly flows and deforms under stresses induced by its weight. As it moves, it abrades rock and debris from its substrate to create landforms such as cirques, moraines, or fjords. Although a glacier may flow into a body of water, it forms only on land and is distinct from the much thinner sea ice and lake ice that form on the surface of bodies of water. On Earth, 99% of glacial ice is contained within vast ice sheets (also known as "continental glaciers") in the polar regions, but glaciers may be found in mountain ranges on every continent other than the Australian mainland, including Oceania's high-latitude oceanic island countries such as New Zealand. Between lati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctic Ice Sheet
The Antarctic ice sheet is one of the two polar ice caps of Earth. It covers about 98% of the Antarctic continent and is the largest single mass of ice on Earth, with an average thickness of over 2 kilometers. It covers an area of almost and contains of ice. A cubic kilometer of ice weighs approximately 0.92 metric gigatonnes, meaning that the ice sheet weighs ~24,380,000 gigatonnes. It holds approximately 61% of all fresh water on Earth, equivalent to about 58 meters of sea level rise if all the ice were above sea level. In East Antarctica, the ice sheet rests on a major land mass, while in West Antarctica the bed can extend to more than 2,500 m below sea level. Satellite measurements by NASA indicate a still increasing sheet thickness above the continent, outweighing the losses at the edge. The reasons for this are not fully understood, but suggestions include the climatic effects on ocean and atmospheric circulation of the ozone hole, and/or cooler ocean surface temperatu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Field
An ice field (also spelled icefield) is a mass of interconnected valley glaciers (also called mountain glaciers or alpine glaciers) on a mountain mass with protruding rock ridges or summits. They are often found in the colder climates and higher altitudes of the world where there is sufficient precipitation for them to form. The higher peaks of the underlying mountain rock that protrude through the icefields are known as nunataks. Ice fields are larger than alpine glaciers, but smaller than ice caps and ice sheets. The topography of ice fields is determined by the shape of the surrounding landforms, while ice caps have their own forms overriding underlying shapes. Formation Ice fields are formed by a large accumulation of snow which, through years of compression and freezing, turns into ice. Due to ice's susceptibility to gravity, ice fields usually form over large areas that are basins or atop plateaus, thus allowing a continuum of ice to form over the landscape uninterrupted b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Cap
In glaciology, an ice cap is a mass of ice that covers less than of land area (usually covering a highland area). Larger ice masses covering more than are termed ice sheets. Description Ice caps are not constrained by topographical features (i.e., they will lie over the top of mountains). By contrast, ice masses of similar size that ''are'' constrained by topographical features are known as ice fields. The ''dome'' of an ice cap is usually centred on the highest point of a massif. Ice flows away from this high point (the ice divide) towards the ice cap's periphery. Ice caps have significant effects on the geomorphology of the area that they occupy. Plastic moulding, gouging and other glacial erosional features become present upon the glacier's retreat. Many lakes, such as the Great Lakes in North America, as well as numerous valleys have been formed by glacial action over hundreds of thousands of years. On Earth, there are about of total ice mass. The average temperature ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Sheet
In glaciology, an ice sheet, also known as a continental glacier, is a mass of glacial ice that covers surrounding terrain and is greater than . The only current ice sheets are in Antarctica and Greenland; during the Last Glacial Period at Last Glacial Maximum, the Laurentide Ice Sheet covered much of North America, the Weichselian ice sheet covered Northern Europe and the Patagonian Ice Sheet covered southern South America. Ice sheets are bigger than ice shelves or alpine glaciers. Masses of ice covering less than 50,000 km2 are termed an ice cap. An ice cap will typically feed a series of glaciers around its periphery. Although the surface is cold, the base of an ice sheet is generally warmer due to geothermal heat. In places, melting occurs and the melt-water lubricates the ice sheet so that it flows more rapidly. This process produces fast-flowing channels in the ice sheet — these are ice streams. The present-day polar ice sheets are relatively young in geol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rwenzori
The Ruwenzori, also spelled Rwenzori and Rwenjura, are a range of mountains in eastern equatorial Africa, located on the border between Uganda and the Democratic Republic of the Congo. The highest peak of the Ruwenzori reaches , and the range's upper regions are permanently snow-capped and glaciated. Rivers fed by mountain streams form one of the sources of the Nile. Because of this, European explorers linked the Ruwenzori with the legendary Mountains of the Moon, claimed by the Greek scholar Ptolemy as the source of the Nile. Virunga National Park in eastern DR Congo and Rwenzori Mountains National Park in southwestern Uganda are located within the range. Geology The mountains formed about three million years ago in the late Pliocene epoch and are the result of an uplifted block of crystalline rocks including gneiss, amphibolite, granite and quartzite. The Rwenzori mountains are the highest non-volcanic, non-orogenic mountains in the world. This uplift divided the pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Kenya
Mount Kenya (Kikuyu: ''Kĩrĩnyaga'', Kamba, ''Ki Nyaa'') is the highest mountain in Kenya and the second-highest in Africa, after Kilimanjaro. The highest peaks of the mountain are Batian (), Nelion () and Point Lenana (). Mount Kenya is located in the former Eastern and Central provinces of Kenya; its peak is now the intersection of Meru, Embu, Laikipia, Kirinyaga, Nyeri and Tharaka Nithi counties, about south of the equator, around north-northeast of the capital Nairobi. Mount Kenya is the source of the name of the Republic of Kenya. Mount Kenya is a volcano created approximately 3 million years after the opening of the East African Rift. Before glaciation, it was high. It was covered by an ice cap for thousands of years. This has resulted in very eroded slopes and numerous valleys radiating from the peak. There are currently 11 small glaciers, which are shrinking rapidly, and may disappear by 2050. The forested slopes are an important source of water for much of Keny ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Kilimanjaro
Mount Kilimanjaro () is a dormant volcano in Tanzania. It has three volcanic cones: Kibo, Mawenzi, and Shira. It is the highest mountain in Africa and the highest free-standing mountain above sea level in the world: above sea level and about above its plateau base. It is the highest volcano in Africa and the Eastern Hemisphere. Kilimanjaro is the fourth most topographically prominent peak on Earth. It is part of Kilimanjaro National Park and is a major hiking and climbing destination. Because of its shrinking glaciers and ice fields, which are projected to disappear between 2025 and 2035, it has been the subject of many scientific studies. Toponymy The origin of the name Kilimanjaro is not known, but a number of theories exist. European explorers had adopted the name by 1860 and reported that Kilimanjaro was the mountain's Kiswahili name. The 1907 edition of ''The Nuttall Encyclopædia'' also records the name of the mountain as Kilima-Njaro. Johann Ludwig Krapf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
