Related topics: climate change · glaciers · sea level rise · sea level · ice

Arctic could be ice-free a decade earlier than thought

The Arctic Ocean's ice cap will disappear in summer as soon as the 2030s and a decade earlier than thought, no matter how aggressively humanity draws down the carbon pollution that drives global warming, scientists said Tuesday.

Ground beneath Thwaites Glacier mapped for first time

The ground beneath Antarctica's most vulnerable glacier has been mapped for the first time, helping scientists to better understand how it is being affected by climate change. Analysis of the geology below the Thwaites Glacier ...

1.5C of warming is too hot for a just world: study

Curbing global heating at 1.5 degrees Celsius will avert runaway climate change but not mass suffering in developing nations, a consortium of 50 researchers warned Wednesday.

Rocks beneath Antarctic Ice Sheet reveal surprising past

The West Antarctic Ice Sheet is shrinking, with many glaciers across the region retreating and melting at an alarming rate. However, this was not always the case according to new research published last month (April 28) in ...

Researchers discover a cause of rapid ice melting in Greenland

While conducting a study of Petermann Glacier in northwest Greenland, researchers at the University of California, Irvine and NASA's Jet Propulsion Laboratory uncovered a previously unseen way in which the ice and ocean interact. ...

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Ice sheet

An ice sheet is a mass of glacier ice that covers surrounding terrain and is greater than 50,000 km² (20,000 mile²). 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 Canada and 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 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.

This text uses material from Wikipedia, licensed under CC BY-SA