Ice sheet

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. The Greenland ice sheet occupies about 82% of the surface of Greenland, and if melted would cause sea levels to rise by 7.2 metres.

The ice sheet is almost 2400 km long in a north-south direction, and its greatest width is 1100 km at a latitude of 77°N, near its northern margin.

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.

The Last Glacial Maximum (LGM) was the most recent time during the Last Glacial Period when ice sheets were at their greatest extent.

An ice sheet, also known as a continental glacier, is a mass of glacial ice that covers surrounding terrain and is greater than 50000 km2.

Sufficiently thin ice sheets allow light to pass through while protecting the underside from short-term weather extremes such as wind chill.

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.

The Laurentide Ice Sheet was a massive sheet of ice that covered millions of square kilometers, including most of Canada and a large portion of the northern United States, multiple times during the Quaternary glacial epochs— from 2.588 ± 0.005 million years ago to the present.

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.

Approximately 61 percent of all fresh water on the Earth is held in the Antarctic ice sheet, an amount equivalent to about 58 m of sea-level rise.

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.

The last glacial period is sometimes colloquially referred to as the "last ice age", though this use is incorrect because an ice age is a longer period of cold temperature in which year-round ice sheets are present near one or both poles.

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.

It was characterized by a large ice sheet (the Fenno-Scandian ice sheet) that spread out from the Scandinavian Mountains and extended as far as the east coast of Schleswig-Holstein, the March of Brandenburg and Northwest Russia.

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.

The Patagonian Ice Sheet was a large elongated and narrow ice sheet centered in the southern Andes that existed during the Llanquihue glaciation.

Ice sheets are bigger than ice shelves or alpine glaciers.

An ice shelf is a thick suspended platform of ice that forms where a glacier or ice sheet flows down to a coastline and onto the ocean surface.

Masses of ice covering less than 50,000 km 2 are termed an ice cap.

Larger ice masses covering more than 50,000 km 2 are termed ice sheets.

This process produces fast-flowing channels in the ice sheet — these are ice streams.

A fast-moving ice or ice stream is a region of an ice sheet that moves significantly faster than the surrounding ice.

The Antarctic ice sheet is divided by the Transantarctic Mountains into two unequal sections called the East Antarctic ice sheet (EAIS) and the smaller West Antarctic Ice Sheet (WAIS).

The East Antarctic Ice Sheet (EAIS) is one of two large ice sheets in Antarctica, and the largest on the entire planet.

The Antarctic ice sheet is divided by the Transantarctic Mountains into two unequal sections called the East Antarctic ice sheet (EAIS) and the smaller West Antarctic Ice Sheet (WAIS).

The WAIS is classified as a marine-based ice sheet, meaning that its bed lies well below sea level and its edges flow into floating ice shelves.

An ice sheet, also known as a continental glacier, is a mass of glacial ice that covers surrounding terrain and is greater than 50000 km2. Ice sheets are bigger than ice shelves or alpine glaciers.

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 including Oceania's high-latitude oceanic island countries such as New Zealand and Papua New Guinea.

According to the Intergovernmental 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 acceleration is due mostly to human-caused global warming, which is driving thermal expansion of seawater and melt of land-based ice sheets and glaciers.

These measurements came from NASA's Gravity Recovery and Climate Experiment (GRACE) satellite, launched in 2002, as reported by BBC News in August 2006.

From the thinning of ice sheets to the flow of water through aquifers and the slow currents of magma inside Earth, mass measurements provided by GRACE help scientists better understand these important natural processes.

The WAIS is bounded by the Ross Ice Shelf, the Ronne Ice Shelf, and outlet glaciers that drain into the Amundsen Sea.

The sea is mostly ice-covered, and the Thwaites Ice Tongue protrudes into it. The ice sheet which drains into the Amundsen Sea averages about 3 km in thickness; roughly the size of the state of Texas, this area is known as the Amundsen Sea Embayment (ASE); it forms one of the three major ice-drainage basins of the West Antarctic Ice Sheet.

The Greenland ice sheet occupies about 82% of the surface of Greenland, and if melted would cause sea levels to rise by 7.2 metres.

The weight of the ice sheet has depressed the central land area to form a basin lying more than 300 m below sea level, while elevations rise suddenly and steeply near the coast.

The EAIS rests on a major land mass but the bed of the WAIS is, in places, more than 2,500 metres below sea level.

Some land movements occur because of isostatic adjustment of the mantle to the melting of ice sheets at the end of the last ice age.

However, in the words of the IPCC, ''"Dynamical processes related to ice flow not included in current models but suggested by recent observations could increase the vulnerability of the ice sheets to warming, increasing future sea level rise. Understanding of these processes is limited and there is no consensus on their magnitude."'' More research work is therefore required to improve the reliability of predictions of ice-sheet response on global warming.

In climate modelling, Ice-sheet models use numerical methods to simulate the evolution, dynamics and thermodynamics of ice sheets, such as the Greenland ice sheet, the Antarctic ice sheet or the large ice sheets on the northern hemisphere during the last glacial period.

However, in the words of the IPCC, ''"Dynamical processes related to ice flow not included in current models but suggested by recent observations could increase the vulnerability of the ice sheets to warming, increasing future sea level rise. Understanding of these processes is limited and there is no consensus on their magnitude."'' More research work is therefore required to improve the reliability of predictions of ice-sheet response on global warming.

Abrupt climate change, cold blob (North Atlantic): Climate change could result in global, large-scale changes in natural and social systems. Examples include ocean acidification caused by increased atmospheric concentrations of carbon dioxide, and the long-term melting of ice sheets, which contributes to sea level rise. Some large-scale changes could occur abruptly, i.e., over a short time period, and might also be irreversible. Examples of abrupt climate change are the rapid release of methane and carbon dioxide from permafrost, which would lead to amplified global warming. Another example is the possibility for the Atlantic Meridional Overturning Circulation to slow- or shutdown (see also shutdown of thermohaline circulation). This could trigger cooling in the North Atlantic, Europe, and North America. It would particularly affect areas such as the British Isles, France and the Nordic countries, which are warmed by the North Atlantic drift.

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.

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.

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.

Although the surface is cold, the base of an ice sheet is generally warmer due to geothermal heat.