Ellesmere Ice Shelf

The former Ellesmere Ice Shelf was the largest ice shelf in the Arctic, encompassing about 3,500 square miles (9,100 km2) of the north coast of Ellesmere Island, Nunavut, Canada.[1] The ice shelf was first documented by the British Arctic Expedition of 1875-76, in which Lieutenant Pelham Aldrich's party went from Cape Sheridan (82.47°N, 61.50°W) west to Cape Alert (82.27°N, 85.55°W).[2] The continuous mass of the Ellesmere Ice Shelf had been in place for at least 3,000 years.[1]

During the twentieth century the Ellesmere Ice Shelf broke up into six separate shelves, the largest being the Ward Hunt Ice Shelf. During the 1980s reassuring official science reported that the remnants were stable .

Main article: Ward Hunt Ice Shelf

In April 2000, satellite images revealed that a large crack in the Ward Hunt shelf had begun to form, and in 2003 it was announced that the ice sheet had split completely in two in 2002, releasing a huge pool of fresh water from the largest epishelf lake in the Northern Hemisphere, located in Disraeli Fjord.[3] In April 2008, it was discovered that the shelf was fractured into dozens of deep, multi-faceted cracks.[4]

Main article: Ayles Ice Shelf

On August 13, 2005, The Ayles Ice Shelf, which was located at (83°1.5′N 77°33.5′W / 83.0250°N 77.5583°W / 83.0250; -77.5583), approximately 800 km (500 mi) south of the North Pole, broke away from the coast forming the giant Ayles Ice Island 37 metres (121 ft) thick and measuring around 14 km (8.7 mi) by 5 km (3.1 mi) in size with an area of approximately 66 km² (25.5 sq mi) or 2.6 km3 (0.62 cu mi) in volume.[1]

The Milne Ice Shelf is the second large segment of the former Ellesmere Ice Shelf.

Notes

  1. 1 2 3 David Ljunggren (2008-07-29). "Giant chunks break off Canadian ice shelf". Reuters. Archived from the original on 2012-12-05. Retrieved 2008-07-29. Mueller initially estimated that 1.5 square miles of ice had broken off the shelf but increased that figure to eight square miles after studying the data more closely. "Whatever has kept this ice shelf in balance for 3,000 years is no longer keeping it in balance," he told Reuters, saying he too would not be surprised to see more ice breaking away from the Ward Hunt shelf this year.
  2. ↑ Martin O. Jeffries, "Ice Island Calvings and Ice Shelf Changes, Milne Ice Shelf and Ayles Ice Shelf, Ellesmere Island, N.W.T.. Arctic 39 (1) (March 1986)
  3. ↑ NASA Earth Observatory. "Breakup of the Ward Hunt Ice Shelf".
  4. ↑ Bob Weber, The Canadian Press (2008-04-12). "Cracks in Arctic ice shelf signal its demise". The Star. Toronto. Retrieved 2010-05-01.
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