Ross Ice Shelf
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What is the Ross Ice Shelf?
The Ross Ice Shelf, the worldâs largest floating ice body, is in Antarctica at the head of the Ross Sea. It lies between 155° W and 160° E longitude, and 78° S and 86° S latitude. Its area is about 182,000 square miles (472,000 square km), about the size of the Yukon territory in Canada.
The shelf's great white barrier wall was first seen in 1841 by British polar explorer James Clark Ross. The ice shelf is fed primarily by giant glaciers, or ice streams, that transport ice down to it from the high polar ice sheet of East and West Antarctica. The Ross Ice Shelf is relatively thin and flexible and only loosely attached to adjoining lands.
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Where is the Ross Ice Shelf located in Antarctica?
The Ross Ice Shelf, the worldâs largest body of floating ice, is located at the head of the Ross Sea in Antarctica. It lies between 155° W and 160° E longitude and 78° S and 86° S latitude, with an area of about 182,000 square miles (472,000 square km). The great white barrier wall of the shelf stretches about 500 miles (800 km) between Ross Island and the Edward VII Peninsula. Fed by giant glaciers from the high polar ice sheet of East and West Antarctica, the Ross Ice Shelf is relatively thin, flexible, and loosely attached to adjoining lands.
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How large is the Ross Ice Shelf?
The Ross Ice Shelf, the worldâs largest body of floating ice, is located in Antarctica at the head of the Ross Sea. It lies between 155° W and 160° E longitude, and 78° S and 86° S latitude. Its area is currently estimated to be approximately 182,000 square miles (472,000 square km), which is about the size of the Yukon territory in Canada. The shelf has a great white barrier wall that rises to 160 to 200 feet (50 to 60 meters) high and stretches about 500 miles (800 km) between anchor points on Ross Island and the Edward VII Peninsula.
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How does the Ross Ice Shelf form and stay in place?
The Ross Ice Shelf, the worldâs largest floating ice body, is fed by glaciers that transport ice from the Antarctic ice sheets. This ice shelf is relatively thin and flexible, loosely attached to the land, and likened to a vast raft.
The shelf remains in place because it is partly grounded on the sea bottom and attached to rocks and islands. The forward movement of the ice shelf is terminated by sea currents. The shelf experiences continual change via calving and melting that accompany the northward movement of the shelf ice.
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Why is the Ross Ice Shelf important to scientists?
The Ross Ice Shelf is important to scientists for several reasons:
* Exploration gateway The shelf has served as a crucial entry point for explorations into the Antarctic interior, facilitating expeditions by famous explorers.
* Climate records Ice sheets, such as the Ross Ice Shelf, hold unique records of past climates, including atmospheric conditions, volcanic activity, and temperatures. Scientists analyze ice cores to gain insights into climate change processes.
* West Antarctic Ice Sheet (WAIS) dynamics The Ross Ice Shelf is largely fed by ice streams from the WAIS, and changes in these ice streams can affect the grounding line, potentially leading to significant alterations in the WAIS and a major rise in global sea levels.
* Marine Protected Area: The Ross Sea, including the Ross Ice Shelf, is part of the worldâs largest marine protected area, established to conserve the region's unique environment.4 Britannica SourcesCreated from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles. -
How does climate change affect the Ross Ice Shelf and the global environment?
The Ross Ice Shelf, the worldâs largest body of floating ice, is vulnerable to climate change, which has implications for the global environment.
Global warming causes the melting of ice sheets and glaciers, as well as thermal expansion of water, leading to sea level rise. The melting of the West Antarctic Ice Sheet, which could be destabilized as the Ross Ice Shelf thins, may lead to a substantial rise in sea level. If losses from iceberg calving and ice-shelf melting are greater than gains from snowfall, global sea levels will rise. Increased melting of the Greenland Ice Sheet is also contributing to sea level rise.
Sea level rise threatens to submerge islands and lowland regions, including major cities such as Tokyo, New York, and Shanghai.
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Ross Ice Shelf, worldâs largest body of floating ice, lying at the head of Ross Sea, itself an enormous indentation in the continent of Antarctica. The ice shelf lies between about 155° W and 160° E longitude and about 78° S and 86° S latitude. The current estimate of its area is about 182,000 square miles (472,000 square km), making it roughly the size of the Yukon territory in Canada. The shelf has served as an important gateway for explorations of the Antarctic interior, including those carried out by many of the most famous expeditions.
The great white barrier wall of the shelfâs front, first seen in 1841 by the British polar explorer James Clark Ross, rises in places to 160 or 200 feet (50 or 60 meters) high and stretches about 500 miles (800 km) between fixed âanchor pointsâ on Ross Island to the west and the jutting Edward VII Peninsula on the east. With its immense, gently undulating surface reaching back nearly 600 miles (950 km) southward into the heart of Antarctica, the Ross Ice Shelf provides the best surface approach into the continental interior. The McMurdo Sound region on the shelfâs western edge thus became the headquarters for Robert F. Scottâs 1911â12 epic sledging trip to the South Pole and also served several Antarctic research programs later in the century. The eastern barrier regions of the ice shelf were headquarters for the Norwegian Roald Amundsenâs first attainment of the South Pole on December 14, 1911; for Richard E. Byrdâs three U.S. expeditions of 1928â41 at Little America IâIII stations; and for several subsequent expeditions and research programs.
The Ross Ice Shelf is fed primarily by giant glaciers, or ice streams, that transport ice down to it from the high polar ice sheet of East and West Antarctica. The ice shelf has been likened to a vast triangular raft because it is relatively thin and flexible and is only loosely attached to adjoining lands. Giant rifts develop behind the ice shelfâs barrier wall and occasionally rupture completely to spawn the huge tabular icebergs that are so characteristic of the Antarctic Ocean. Thus, although the barrierâs position appears almost stationary, it actually undergoes continual change by calving and melting that accompany northward movement of the shelf ice. The shelfâs mean ice thickness is about 1,100 feet (330 meters) along a line at about 79° S latitude. In a southward direction along about 168° W longitude, the ice shelfâs thickness gradually increases to more than 2,300 feet (700 meters). Estimates suggest that at distances of 100 to 200 miles (160 to 320 km) inland from the barrier, 15 to 20 inches (380 to 500 mm) of ice may be added to the shelf each year by bottom freezing. Melting on the bottom of the ice shelf also occurs, and oceanographic data suggest that the net effect is the dissolution of the ice shelf by about 47â87 inches (120â220 cm) per year.
