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Sea Ice
Sea ice arises as seawater freezes. Because ice is less density, dense than water, it floats on the ocean's surface (as does fresh water ice). Sea ice covers about 7% of the Earth's surface and about 12% of the world's oceans. Much of the world's sea ice is enclosed within the polar ice packs in the Earth's polar regions: the Arctic ice pack of the Arctic Ocean and the Antarctic ice pack of the Southern Ocean. Polar packs undergo a significant yearly cycling in surface extent, a natural process upon which depends the Arctic ecology, including the Arctic sea ice ecology and history, ocean's ecosystems. Due to the action of winds, currents and temperature fluctuations, sea ice is very dynamic, leading to a wide variety of ice types and features. Sea ice may be contrasted with icebergs, which are chunks of ice shelf, ice shelves or glaciers that Ice calving, calve into the ocean. Depending on location, sea ice expanses may also incorporate icebergs. General features and dynamics ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic Ice
The Arctic ice pack is the sea ice cover of the Arctic Ocean and its vicinity. The Arctic ice pack undergoes a regular seasonal cycle in which ice melts in spring and summer, reaches a minimum around mid-September, then increases during fall and winter. Summer ice cover in the Arctic is about 50% of winter cover. Some of the ice survives from one year to the next. Currently, 28% of Arctic basin sea ice is multi-year ice, thicker than seasonal ice: up to thick over large areas, with ridges up to thick. Besides the regular seasonal cycle there has been an underlying trend of declining sea ice in the Arctic in recent decades as well. Climatic importance Energy balance effects Sea ice has an important effect on the heat balance of the polar oceans, since it insulates the (relatively) warm ocean from the much colder air above, thus reducing heat loss from the oceans. Sea ice is highly reflective of solar radiation, reflecting about 60% of incoming solar radiation when bar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fast Ice
Fast ice (also called ''land-fast ice'', ''landfast ice'', and ''shore-fast ice'') is sea ice or lake ice that is "fastened" to the coastline, to the sea floor along shoals, or to grounded icebergs.Leppäranta, M. 2011. The Drift of Sea Ice. Berlin: Springer-Verlag. Fast ice may either grow in place from the sea water or by freezing pieces of drifting ice to the shore or other anchor sites.Kovacs, A.and M. Mellor. 1974. "Sea ice morphology and ice as a geologic agent in the Southern Beaufort Sea." pp. 113-164, in: ''The Coast and Shelf of the Beaufort Sea'', J.C. Reed and J.E. Sater (Eds.), Arlington, Va.: U.S.A. Unlike drift (or pack) ice, fast ice does not move with currents and winds. The width (and the presence) of this ice zone is usually seasonal and depends on ice thickness, topography of the sea floor and islands. It ranges from a few meters to several hundred kilometers. Seaward expansion is a function of a number of factors, notably water depth, shoreline prote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drift Ice
Drift or Drifts may refer to: Geography * Drift or ford (crossing) of a river * Drift (navigation), difference between heading and course of a vessel * Drift, Kentucky, unincorporated community in the United States * In Cornwall, England: ** Drift, Cornwall, village ** Drift Reservoir, associated with the village Science, technology, and physics * Directional Recoil Identification from Tracks, a dark-matter experiment * Drift (video gaming), a typical game-controller malfunction * Drift pin, metalworking tool for localizing hammer blows and for aligning holes * Drift (geology), deposited material of glacial origin * drift (in mining), a roughly horizontal passage; an adit * Drift, linear term of a stochastic process * Drift (motorsport), the controlled sliding of a vehicle through a sharp turn, either via over-steering with sudden sharp braking, or counter-steering with a sudden "clutch kick" acceleration * Incremental changes: ** Drift (linguistics), a type of language ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctic
The Antarctic (, ; commonly ) is the polar regions of Earth, polar region of Earth that surrounds the South Pole, lying within the Antarctic Circle. It is antipodes, diametrically opposite of the Arctic region around the North Pole. The Antarctic comprises the continent of Antarctica, the Kerguelen Plateau, and other list of Antarctic and Subantarctic islands, island territories located on the Antarctic Plate or south of the Antarctic Convergence. The Antarctic region includes the ice shelf, ice shelves, waters, and all the island territories in the Southern Ocean situated south of the Antarctic Convergence, a zone approximately wide and varying in latitude seasonally. The region covers some 20 percent of the Southern Hemisphere, of which 5.5 percent (14 million km2) is the surface area of the Antarctica continent itself. All of the land and ice shelf, ice shelves south of 60th parallel south, 60°S latitude are administered under the Antarctic Treaty System. Biogeograph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic
The Arctic (; . ) is the polar regions of Earth, polar region of Earth that surrounds the North Pole, lying within the Arctic Circle. The Arctic region, from the IERS Reference Meridian travelling east, consists of parts of northern Norway (Nordland, Troms, Finnmark, Svalbard and Jan Mayen), northernmost Sweden (Västerbotten, Norrbotten and Lapland (Sweden), Lappland), northern Finland (North Ostrobothnia, Kainuu and Lapland (Finland), Lappi), Russia (Murmansk Oblast, Murmansk, Siberia, Nenets Autonomous Okrug, Nenets Okrug, Novaya Zemlya), the United States (Alaska), Canada (Yukon, Northwest Territories, Nunavut), Danish Realm (Greenland), and northern Iceland (Grímsey and Kolbeinsey), along with the Arctic Ocean and adjacent seas. Land within the Arctic region has seasonally varying cryosphere, snow and ice cover, with predominantly treeless permafrost under the tundra. Arctic seas contain seasonal sea ice in many places. The Arctic region is a unique area among Earth's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Guardian
''The Guardian'' is a British daily newspaper. It was founded in Manchester in 1821 as ''The Manchester Guardian'' and changed its name in 1959, followed by a move to London. Along with its sister paper, ''The Guardian Weekly'', ''The Guardian'' is part of the Guardian Media Group, owned by the Scott Trust Limited. The trust was created in 1936 to "secure the financial and editorial independence of ''The Guardian'' in perpetuity and to safeguard the journalistic freedom and liberal values of ''The Guardian'' free from commercial or political interference". The trust was converted into a limited company in 2008, with a constitution written so as to maintain for ''The Guardian'' the same protections as were built into the structure of the Scott Trust by its creators. Profits are reinvested in its journalism rather than distributed to owners or shareholders. It is considered a newspaper of record in the UK. The editor-in-chief Katharine Viner succeeded Alan Rusbridger in 2015. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Eggs
Ice eggs, or ice balls, are a rare phenomenon caused by a process in which small pieces of sea ice in open water are rolled over by wind and currents in freezing conditions and grow into spheroid pieces of ice. They may collect into heaps of balls or 'eggs' on beaches where they pack together in striking patterns. The gentle churn of water, blown by a suitably stiff breeze makes concentric layers of ice form on a seed particle that then grows into the floating ball as it rolls through the freezing currents. Given enough time, the frozen balls can grow to become boulder size. In 2016, giant snowballs washed up on a beach in Siberia, some measuring a metre (about 3 feet) across. An ice specialist from the Finnish Meteorological Institute has been quoted as saying ice balls are rare, but not unprecedented, and occur about once a year on the Finnish coastline as conditions allow. They also appear on the Great Lakes, North American Great Lakes along with pancake ice, forming in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pancake Ice
Pancake ice is a form of sea ice that consists of round pieces of ice with diameters ranging from 30 centimetres (12 in) to 3 metres (9.8 ft) and thicknesses up to 10 centimetres (3.9 inches), depending on the local conditions. It forms as a result of wave action on slush or ice rind. Characteristics Pancake ice features elevated rims formed by piling of frazil ice or slush onto the edges of pancakes when they collide, both due to random bumping into each other and because of periodic compressions at wave troughs. These rims are the first indication of the onset of the formation of the pancake ice from less consolidated forms of ice. Formation Pancake ice forms in conditions of high wave activity, in contrast to other types of sea ice formed under calm conditions. Pancake ice can form in two processes: (1) on water covered to some degree in slush, shuga or grease ice, or (2) from breaking of ice rind, nilas or even gray ice in agitated conditions. If the waves ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grease Ice
Grease ice is a very thin, soupy layer of frazil crystals clumped together, and only formed in large, open bodies of water most notably the ocean. Grease ice makes the water resemble an oil slick, the small crystals of ice held closely together reflect and refract light similarly to how oil will on water. Grease ice is the second stage in the formation of ice floes being the stage immediately following the frazil ice stage. Outside the ocean and seas, the Laurentian Great Lakes and Lake Baikal also form grease ice. New sea ice formation takes place throughout the winter in the Arctic, and Antarctic where frazil forms and coalesces in polynyas or in cold-exposed regions of the open-ocean. Similarly, in seas and lakes, where latent energy is sufficient (waves, swells, fetch, tides, seiche, etc), turbulence mixes the frazil ice down into the upper layer and forms a surface layer of grease ice. The term ‘grease ice’ follows World Meteorological Organization nomenclatur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shuga (ice)
Shuga is a spongy, porridgy body of ice suspended in water. It may be formed from grease ice or from anchor ice rising to the surface and typically comprises lumps of ice, a few centimeters across. Shuga is the third stage in the development of sea ice, formed as a result of snow falling on frazil ice to become grease ice which is then further worked by subsequent wind and wave action. As cooling continues, the next stage is reached when sheets of rind or nilas Sea ice arises as seawater freezes. Because ice is less dense than water, it floats on the ocean's surface (as does fresh water ice). Sea ice covers about 7% of the Earth's surface and about 12% of the world's oceans. Much of the world's sea ic ... ice emerge.Strangeways (2003), p. 461. Shuga may also occur in freshwater situations. References Bibliography * Armstrong, Terence, Brian Roberts and Charles Swithinbank (1973). ''Illustrated Glossary of Snow of Ice''. Cambridge: Scott Polar Research Institute. * Hin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Slush
Slush, also called slush ice, is a slurry mixture of small ice crystals (e.g. snow) and liquid water. In the natural environment, slush forms when ice or snow melts or during mixed precipitation. This often mixes with dirt and other pollutants on the surface, resulting in a gray or muddy brown color. Often, solid ice or snow can block the drainage of fluid water from slushy areas, so slush often goes through multiple freeze/thaw cycles before being able to completely drain and disappear. In areas where road salt is used to clear roadways, slush forms at lower temperatures in salted areas than it would ordinarily. This can produce a number of different consistencies over the same geographical area with scattered salted areas covered with slush and others covered with frozen precipitation. Hazards Because slush behaves like a non-Newtonian fluid, which means it behaves like a mostly solid mass until its inner shear forces rise beyond a specific threshold and beyond can ve ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
