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Totten Glacier
Totten Glacier is a large glacier draining a major portion of the East Antarctic Ice Sheet, through the Budd Coast of Wilkes Land in the Australian Antarctic Territory. The catchment drained by the glacier is estimated at , extending approximately into the interior and holds the potential to raise sea level by at least . Totten drains northeastward from the continental ice but turns northwestward at the coast where it terminates in a prominent tongue close east of Cape Waldron. It was first delineated from aerial photographs taken by USN Operation Highjump (1946–47), and named by Advisory Committee on Antarctic Names (US-ACAN) for George M. Totten, midshipman on of the United States Exploring Expedition (1838–42), who assisted Lieutenant Charles Wilkes with correction of the survey data obtained by the expedition. Totten Ice Shelf is a floating portion of Totten Glacier, laterally bounded by the Aurora Subglacial Basin to the south and Law Dome to the north. The ice she ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctica
Antarctica () is Earth's southernmost and least-populated continent. Situated almost entirely south of the Antarctic Circle and surrounded by the Southern Ocean, it contains the geographic South Pole. Antarctica is the fifth-largest continent, being about 40% larger than Europe, and has an area of . Most of Antarctica is covered by the Antarctic ice sheet, with an average thickness of . Antarctica is, on average, the coldest, driest, and windiest of the continents, and it has the highest average elevation. It is mainly a polar desert, with annual precipitation of over along the coast and far less inland. About 70% of the world's freshwater reserves are frozen in Antarctica, which, if melted, would raise global sea levels by almost . Antarctica holds the record for the lowest measured temperature on Earth, . The coastal regions can reach temperatures over in summer. Native species of animals include mites, nematodes, penguins, seals and tardigrades. Where vegetation o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grounding Line
Marine ice sheet instability (MISI) describes the potential for ice sheets grounded below sea level to destabilize in a runaway fashion. The mechanism was first proposed in the 1970s by Johannes Weertman and was quickly identified as a means by which even gradual anthropogenic warming could lead to relatively rapid sea level rise. In Antarctica, the West Antarctic Ice Sheet, the Aurora Subglacial Basin, and the Wilkes Basin are each grounded below sea level and are inherently subject to MISI. General The term ''marine ice sheet'' describes an ice sheet whose base rests on ground below sea level, and ''marine ice sheet instability'' describes the inherent precarious nature of marine ice sheets due to Archimedes' principle. Because seawater is denser than ice, marine ice sheets can only remain stable where the ice is thick enough for its mass to exceed the mass of the seawater displaced by the ice. In other words, wherever ice exists below sea level, it is held in place only by the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Retreat Of Glaciers Since 1850
The retreat of glaciers since 1850 affects the availability of fresh water for irrigation and domestic use, mountain recreation, animals and plants that depend on glacier-melt, and, in the longer term, the level of the oceans. Deglaciation occurs naturally at the end of ice ages, but glaciologists find the current glacier retreat is accelerated by the measured increase of atmospheric greenhouse gases—an effect of climate change. Mid-latitude mountain ranges such as the Himalayas, Rockies, Alps, Cascades, Southern Alps, and the southern Andes, as well as isolated tropical summits such as Mount Kilimanjaro in Africa, are showing some of the largest proportionate glacial losses. Excluding peripheral glaciers of ice sheets, the total cumulated global glacial losses over the 26 year period from 1993–2018 were likely 5500 gigatons, or 210 gigatons per yr.Fox-Kemper, B., H.T. Hewitt, C. Xiao, G. Aðalgeirsdóttir, S.S. Drijfhout, T.L. Edwards, N.R. Golledge, M. Hemer, R.E. Kopp, G ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Antarctic Ice Streams
This is a list of Antarctic ice streams. A complete list of Antarctic ice streams is not available. Names and locations of Antarctic ice features, including those listed below, can be found in the Scientific Committee on Antarctic Research The Scientific Committee on Antarctic Research (SCAR) is an interdisciplinary body of the International Science Council (ISC). SCAR coordinates international scientific research efforts in Antarctica, including the Southern Ocean. SCAR's scien ..., Gazetteer. Major Antarctic ice drainage systems are given by Rignot and Thomas (2002). These include the ice streams with the greatest flow, which are listed below. References {{authority control * Ice streams ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Glaciers In The Antarctic
There are many glaciers in the Antarctic. This set of lists does not include ice sheets, ice caps or ice fields, such as the Antarctic ice sheet, but includes glacial features that are defined by their flow, rather than general bodies of ice. The lists include outlet glaciers, valley glaciers, cirque glaciers, tidewater glaciers and ice streams. Ice streams are a type of glacier and many of them have "glacier" in their name, e.g. Pine Island Glacier. Ice shelves are listed separately in the List of Antarctic ice shelves. For the purposes of these lists, the Antarctic is defined as any latitude further south than 60° (the continental limit according to the Antarctic Treaty System). List by letters * List of glaciers in the Antarctic: A–H * List of glaciers in the Antarctic: I–Z See also * List of Antarctic and subantarctic islands * List of Antarctic ice rises * List of Antarctic ice shelves * List of Antarctic ice streams * List of glaciers * List of subantar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Stream
An ice stream is a region of fast-moving ice within an ice sheet. It is a type of glacier, a body of ice that moves under its own weight. They can move upwards of a year, and can be up to in width, and hundreds of kilometers in length. They tend to be about deep at the thickest, and constitute the majority of the ice that leaves the sheet. In Antarctica, the ice streams account for approximately 90% of the sheet's mass loss per year, and approximately 50% of the mass loss in Greenland. The shear forces cause deformation and recrystallization that drive the movement, this movement then causes topographic lows and valleys to form after all of the material in the ice sheet has been discharged. Sediment also plays an important role in flow velocity, the softer and more easily deformed the sediment present, the easier it is for flow velocity to be higher. Most ice streams contain a layer of water at the bottom, which lubricates flow and acts to increase speed. Mechanics Ice str ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cape Mikhaylov
Cape Mikhaylov () is an ice-covered point about east of Totten Glacier, Wilkes Land, Antarctica. It was photographed by U.S. Navy Operation Highjump in 1947, and plotted on base compilation maps by Gardner Blodgett of the Office of Geography, U.S. Department of the Interior, in 1955. The cape was photographed by the Soviet Antarctic Expedition The Soviet Antarctic Expedition (SAE or SovAE) (russian: Советская антарктическая экспедиция, САЭ, ''Sovetskaya antarkticheskaya ekspeditsiya'') was part of the Arctic and Antarctic Research Institute of the So ... in 1956, and was named after Pavel N. Mikhaylov, artist with the Bellingshausen expedition of 1819–21. References Headlands of Wilkes Land {{WilkesLand-geo-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sabrina Coast
Sabrina Coast () is that portion of the coast of Wilkes Land, Antarctica, lying between Cape Waldron, at 115° 33' E, and Cape Southard, at 122° 05' E. John Balleny has long been credited with having seen land in March 1839 at about 117° E. The United States Exploring Expedition under Lt. Charles Wilkes approached this coast in February 1840 and indicated its general configuration as shown in part by "Totten High Land" on his 1840 chart. In 1931 the British Australian New Zealand Antarctic Research Expedition (BANZARE) under Douglas Mawson Sir Douglas Mawson OBE FRS FAA (5 May 1882 – 14 October 1958) was an Australian geologist, Antarctic explorer, and academic. Along with Roald Amundsen, Robert Falcon Scott, and Sir Ernest Shackleton, he was a key expedition leader during ... saw what appeared to be land in this longitude about one degree farther south than that reported by Balleny and Wilkes. In recognition of Balleny's effort, Mawson retained the name of the cutter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Circumpolar Deep Water
Circumpolar Deep Water (CDW) is a designation given to the water mass in the Pacific and Indian oceans that is a mixing of other water masses in the region. It is characteristically warmer and saltier than the surrounding water masses, causing CDW to contribute to the melting of ice shelves in the Antarctic region. Physical Properties CDW, the greatest volume water mass in the Southern Ocean, includes the North Atlantic Deep Water (NADW), the Antarctic Bottom Water (AABW), Antarctic Intermediate Water (AAIW), as well as recirculated deep water from the Indian and Pacific Oceans. A distinguishing characteristic of the CDW is that the water is not formed at the surface, but rather by a blending of other water masses. CDW sits at a depth of around 500 meters, approximately at the depth of the continental shelf. There are two types of CDW: Upper Circumpolar Deep Water (UCDW) and Lower Circumpolar Deep Water (LCDW). UCDW originates in the Indian and Pacific Oceans and has lower o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ICESat
ICESat (Ice, Cloud, and land Elevation Satellite) was a NASA satellite mission for measuring ice sheet mass balance, cloud and aerosol heights, as well as land topography and vegetation characteristics. It operated as part of NASA's Earth Observing System (EOS). ICESat was launched 13 January 2003 on a Delta II launch vehicle from Vandenberg Air Force Base in California into a near-circular, near-polar orbit with an altitude of approximately . It operated for seven years before being retired in February 2010, after its scientific payload shut down and scientists were unable to restart it. The ICESat mission was designed to provide elevation data needed to determine ice sheet mass balance as well as cloud property information, especially for stratospheric clouds common over polar areas. It provides topography and vegetation data around the globe, in addition to the polar-specific coverage over the Greenland and Antarctic ice sheets. The satellite was found useful in assessing im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravity Recovery And Climate Experiment
The Gravity Recovery and Climate Experiment (GRACE) was a joint mission of NASA and the German Aerospace Center (DLR). Twin satellites took detailed measurements of Earth's gravity field anomalies from its launch in March 2002 to the end of its science mission in October 2017. The GRACE Follow-On (GRACE-FO) is a continuation of the mission on near-identical hardware, launched in May 2018. By measuring gravity anomalies, GRACE showed how mass is distributed around the planet and how it varies over time. Data from the GRACE satellites is an important tool for studying Earth's ocean, geology, and climate. GRACE was a collaborative endeavor involving the Center for Space Research at the University of Texas at Austin, NASA's Jet Propulsion Laboratory, the German Aerospace Center and Germany's National Research Center for Geosciences, Potsdam. The Jet Propulsion Laboratory was responsible for the overall mission management under the NASA ESSP (Earth System Science Pathfinder) program ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interferometric Synthetic-aperture Radar
Interferometric synthetic aperture radar, abbreviated InSAR (or deprecated IfSAR), is a radar technique used in geodesy and remote sensing. This geodetic method uses two or more synthetic aperture radar (SAR) images to generate maps of surface deformation or digital elevation, using differences in the phase of the waves returning to the satellite or aircraft. The technique can potentially measure millimetre-scale changes in deformation over spans of days to years. It has applications for geophysical monitoring of natural hazards, for example earthquakes, volcanoes and landslides, and in structural engineering, in particular monitoring of subsidence and structural stability. Technique Synthetic aperture radar Synthetic aperture radar (SAR) is a form of radar in which sophisticated processing of radar data is used to produce a very narrow effective beam. It can be used to form images of relatively immobile targets; moving targets can be blurred or displaced in the formed imag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
