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Eklutna Glacier
Eklutna Glacier is a land terminating glacier in Chugach State Park and the Chugach Mountains near Anchorage, Alaska. Runoff from Eklutna Glacier contributes to Eklutna Lake, the main source of drinking water for the Anchorage community as well as hydroelectric power via the Eklutna Hydroelectric Project.Brabets, Timothy P. (1993). Glacier Runoff and Sediment Transport and Deposition: Eklutna Lake Basin, Alaska. ''U.S. Geological Survey''. Water-Resources Investigations Report 92-4132. https://pubs.usgs.gov/wri/1992/4132/report.pdf However, Eklutna Glacier is shrinking in response to climate change which will inevitably affect downstream water resources. Eklutna Glacier is also known by the Dena'ina name: Idlu Bena Li'a. Geology Eklutna Glacier is a 10 km long, 29 square km, valley glacier originating from the Pleistocene epoch. The glacier has two branches that converge about 2.7 km above the glacier terminus. The Main Branch is characterized by a large, low-slopi ... [...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] |
Glacier Terminus
A glacier terminus, toe, or snout, is the end of a glacier at any given point in time. Although glaciers seem motionless to the observer, in reality glaciers are in endless motion and the glacier terminus is always either advancing or retreating. The location of the terminus is often directly related to glacier mass balance, which is based on the amount of snowfall which occurs in the accumulation zone of a glacier, as compared to the amount that is melted in the ablation zone. The position of a glacier terminus is also impacted by localized or regional temperature change over time. Tracking Tracking the change in location of a glacier terminus is a method of monitoring a glacier's movement. The end of the glacier terminus is measured from a fixed position in neighboring bedrock periodically over time. The difference in location of a glacier terminus as measured from this fixed position at different time intervals provides a record of the glacier's change. A similar way of trac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Accumulation Zone
On a glacier, the accumulation zone is the area above the firn line, where snowfall accumulates and exceeds the losses from ablation, (melting, evaporation, and sublimation). The annual equilibrium line separates the accumulation and ablation zone Ablation zone or ''ablation area'' refers to the low-altitude area of a glacier or ice sheet below firn with a net loss in ice mass due to melting, sublimation, evaporation, ice calving, aeolian processes like blowing snow, avalanche, and any ... annually. The accumulation zone is also defined as the part of a glacier's surface, usually at higher elevations, on which there is net accumulation of snow, which subsequently turns into firn and then glacier ice. Part of the glacier where snow builds up and turns to ice moves outward from there. External links * * Glaciology {{Glaciology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ablation Zone
Ablation zone or ''ablation area'' refers to the low-altitude area of a glacier or ice sheet below firn with a net loss in ice mass due to melting, sublimation, evaporation, ice calving, aeolian processes like blowing snow, avalanche, and any other ablation. The equilibrium line altitude (ELA) or snow line separates the ablation zone from the higher-altitude accumulation zone. The ablation zone often contains meltwater features such as supraglacial lakes, englacial streams, and subglacial lakes. Sediments dropped in the ablation zone forming small mounds or hillocks are called kames. Kame and kettle hole topography is useful in identifying an ablation zone of a glacier. The seasonally melting glacier deposits much sediment at its fringes in the ablation area. Ablation constitutes a key part of the glacier mass balance. The amount of snow and ice gained in the accumulation zone and the amount of snow and ice lost in the ablation zone determine glacier mass balance. Often mas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Geological Survey
The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization's work spans the disciplines of biology, geography, geology, and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility. The agency was founded on March 3, 1879. The USGS is a bureau of the United States Department of the Interior; it is that department's sole scientific agency. The USGS employs approximately 8,670 people and is headquartered in Reston, Virginia. The USGS also has major offices near Lakewood, Colorado, at the Denver Federal Center, and Menlo Park, California. The current motto of the USGS, in use since August 1997, is "science for a changing world". The agency's previous slogan, adopted on the occasion of its hundredt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eurasia
Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago and the Russian Far East to the east. The continental landmass is bordered by the Atlantic Ocean and Africa to the west, the Pacific Ocean to the east, the Arctic Ocean to the north, and by Africa, the Mediterranean Sea, and the Indian Ocean to the south. The division between Europe and Asia as two continents is a historical social construct, as many of their borders are over land; thus, in some parts of the world, Eurasia is recognized as the largest of the six, five, or four continents on Earth. In geology, Eurasia is often considered as a single rigid megablock. However, the rigidity of Eurasia is debated based on paleomagnetic data. Eurasia covers around , or around 36.2% of the Earth's total land area. It is also home to the largest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crevasse
A crevasse is a deep crack, that forms in a glacier or ice sheet that can be a few inches across to over 40 feet. Crevasses form as a result of the movement and resulting stress associated with the shear stress generated when two semi-rigid pieces above a plastic substrate have different rates of movement. The resulting intensity of the shear stress causes a breakage along the faces. Description Crevasses often have vertical or near-vertical walls, which can then melt and create seracs, arches, and other ice formations. These walls sometimes expose layers that represent the glacier's stratigraphy. Crevasse size often depends upon the amount of liquid water present in the glacier. A crevasse may be as deep as 45 metres and as wide as 20 metres. by |
Abseiling
Abseiling ( ; ), also known as rappelling ( ; ), is the controlled descent of a steep slope, such as a rock face, by moving down a rope. When abseiling the person descending controls their own movement down the rope, in contrast to Belaying, lowering off in which the rope attached to the person descending is paid out by their belayer. This technique is used by Climbing, climbers, mountaineers, Caving, cavers, Canyoning, canyoners, search and rescue and rope access technicians to descend cliffs or slopes when they are too steep and/or dangerous to descend without protection. Many climbers use this technique to protect established Anchor (climbing), anchors from damage. Rope access technicians also use this as a method to access difficult-to-reach areas from above for various industrial applications like maintenance, construction, inspection and welding. To descend safely, abseilers use a variety of techniques to increase the friction on the rope to the point where it can ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cold-weather Warfare
Cold-weather warfare, also known as arctic warfare or winter warfare, encompasses military operations affected by snow, ice, thawing conditions or cold, both on land and at sea. Cold-weather conditions occur year-round at high elevation or at high latitudes, and elsewhere materialise seasonally during the winter period. Mountain warfare often takes place in cold weather or on terrain that is affected by ice and snow, such as the Alps and the Himalayas. Historically, most such operations have been during winter in the Northern Hemisphere. Some have occurred above the Arctic Circle where snow, ice and cold may occur throughout the year. At times, cold or its aftermath— thaw—has been a decisive factor in the failure of a campaign, as with the French invasion of Russia in 1812, the Soviet invasion of Finland in 1939, and the German invasion of the Soviet Union during World War II. History Northern and Eastern Europe were the venues for some well-documented winter campaigns. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fort Richardson (Alaska)
Fort Richardson is a United States Army installation in the U.S. State of Alaska, adjacent to the city of Anchorage. In 2010, it was merged with nearby Elmendorf Air Force Base to form Joint Base Elmendorf-Richardson. History Fort Richardson was named for the military pioneer explorer, Brig. Gen. Wilds P. Richardson, who served three tours of duty in the rugged Alaska territory between 1897 and 1917. Richardson, a native Texan and an 1884 West Point graduate, commanded troops along the Yukon River and supervised construction of Fort Egbert near Eagle, and Fort William H. Seward (Chilkoot Barracks) near Haines. As head of the War Department's Alaska Road Commission from 1905 to 1917, he was responsible for much of the surveying and building of early railroads, roads and bridges that helped the state's settlement and growth. The Valdez-Fairbanks Trail, surveyed under his direction in 1904, was named the Richardson Highway in his honor. During World War II, Fort Richardson was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in 2009 by the International Union of Geological Sciences, the cutoff of the Pleistocene and the preceding Pliocene was regarded as being 1.806 million years Before Present (BP). Publications from earlier years may use either definition of the period. The end of the Pleistocene corresponds with the end of the last glacial period and also with the end of the Paleolithic age used in archaeology. The name is a combination of Ancient Greek grc, label=none, πλεῖστος, pleīstos, most and grc, label=none, καινός, kainós (latinized as ), 'new'. At the end of the preceding Pliocene, the previously isolated North and South American continents were joined by the Isthmus of Panama, causing Great American Interchang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chugach State Park
Chugach State Park covers 495,204 acres (2,004 square kilometers) immediately east of the Anchorage Bowl in south-central Alaska. Though primarily in the Municipality of Anchorage, a small portion of the park north of the Eklutna Lake area in the vicinity of Pioneer Peak lies within the Matanuska-Susitna Borough. Established by legislation signed into law on August 6, 1970, by Alaska Governor Keith Miller, this state park was created to provide recreational opportunities, protect the scenic value of the Chugach Mountains and other geographic features, and ensure the safety of the water supply for Anchorage. The park, managed by Alaska State Parks, is the third-largest state park in the United States, and consists of geographically disparate areas each with different attractions and facilities.Littlepage, Dean, ''A Falcon Guide Hiking Alaska: A Guide to Alaska's Greatest Hiking Adventures,'' The Globe Pequot Press, Guilford, Connecticut, p. 150 (2006). Only Anza-Borrego Desert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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