Ice Sheet

An ice sheet is a mass of glacier ice that covers surrounding terrain and is greater than 50,000 km2 (19,000 sq mi), thus also known as continental glacier. The only current ice sheets are in Antarctica and Greenland; during the last glacial period at Last Glacial Maximum (LGM) 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 geological terms. The Antarctic Ice Sheet first formed as a small ice cap (maybe several) in the early Oligocene, but retreating and advancing many times until the Pliocene, when it came to occupy almost all of Antarctica. The Greenland ice sheet did not develop at all until the late Pliocene, but apparently developed very rapidly with the first continental glaciation. This had the unusual effect of allowing fossils of plants that once grew on present-day Greenland to be much better preserved than with the slowly forming Antarctic ice sheet.

Read more about Ice Sheet:  Antarctic Ice Sheet, Greenland Ice Sheet, Ice Sheet Dynamics, Predicted Effects of Global Warming

Other articles related to "ice sheet, ice sheets, ice":

Ice Sheet - Predicted Effects of Global Warming
... The Greenland, and probably the Antarctic, ice sheets have been losing mass recently, because losses by melting and outlet glaciers exceed accumulation of snowfall ... Panel on Climate Change (IPCC), loss of Antarctic and Greenland ice sheet mass contributed, respectively, about 0.21 ± 0.35 and 0.21 ± 0.07 mm/year to sea level rise between 1993 and 2003 ... The IPCC projects that ice mass loss from melting of the Greenland ice sheet will continue to outpace accumulation of snowfall ...
Little Tom Mountain - Ancient History
... River basin as the retreating Laurentide ice sheet deposited sediments near Rocky Hill, CT, damming the Connecticut River basin ... Americans just to the south of the glacial ice sheet 18,000 years ago ... These peoples pushed north as the ice sheet retreated ...
Summit Camp - Climate
... Climate data for Automatic Weather Station (AWS), Summit Camp, Greenland Ice Sheet ... Source In July 2012, satellite imagery showed there was an "unprecedented" melt of the Greenland ice sheet ... days from 8 July, the area of thawed surface ice grew from 40% to almost 97% of the entire ice sheet surface ...
The Ice Sheet At Ogden
... The Ice Sheet at Ogden, also known as the Weber County Ice Sheet, is located 35 miles (56 km) north of Salt Lake City on the campus of Weber State University in Ogden ... The Ice Sheet opened in 1994 as a recreational training center for curling, ice hockey, and figure skating ... During the 2002 Winter Olympics the Ice Sheet hosted the curling events ...
Paha (landform) - Origin
... "composed in part of water-laid sand and silt and in part of ice-moulded till." Later, after it came to be understood that loess was wind deposited silt, pahas came to be interpreted as a kind of sand dune ... prevailing northwesterly winds, possibly anticyclonic winds blowing from the retreating ice sheet." Explaining Pahas as a kind of dune does not explain why they are not shaped like other dune forms ... glacial till plains of the Iowan surface during the last ice age ...

Famous quotes containing the words sheet and/or ice:

    As many lies as will lie in thy paper, although the sheet were big enough for the bed of Ware in England.
    William Shakespeare (1564–1616)

    I also heard the whooping of the ice in the pond, my great bed-fellow in that part of Concord, as if it were restless in its bed and would fain turn over, were troubled with flatulency and bad dreams; or I was waked by the cracking of the ground by the frost, as if some one had driven a team against my door, and in the morning would find a crack in the earth a quarter of a mile long and a third of an inch wide.
    Henry David Thoreau (1817–1862)