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Ayles Ice Shelf#Breakup

{{Short description|Ice shelf in the Arctic Ocean}}

{{Use mdy dates|date=October 2022}}

Image:EllesmereIsland July 2002 Cropped - Ayles.jpg

Image:Aylesiceshelf.jpg satellite image taken August 13, 2005, shows the collapse. The newly formed ice island forms only a small part of this picture, being the fragment very close to shore at the centre of the image. The island is ringed in the picture shown [https://www.cbc.ca/news/science/arctic-ice-shelf-collapse-poses-risk-expert-1.615809 in this CBC article].]]

The Ayles Ice Shelf was one of six major ice shelves in Canada, all on the north coast of Ellesmere Island, Nunavut. The ice shelf broke off from the coast on August 13, 2005, forming a giant ice island {{convert|37|m|abbr=on}} thick and measuring around {{convert|14|by|5|km|abbr=on}} in size (approximately {{convert|55|km2|abbr=on}} in area or {{convert|2.6|km3|abbr=on}} in volume). The oldest ice in the ice shelf is believed to be over 3,000 years old. The ice shelf was at ({{coord|82|52|N|80|30|W|type:glacier_scale:3000000_region:CA_source:http://www4.rncan.gc.ca/search-place-names/unique/OABKL|display=inline,title}}), approximately {{convert|800|km|abbr=on}} south of the North Pole.

The Ayles Ice Shelf, like the nearby Mount Ayles, was named for the Arctic explorer, Adam Ayles, who served under George Nares as the Petty Officer of HMS Alert in the British Arctic Expedition.{{cite news |url=http://wairarapa.co.nz/times-age/weekly/2002/ayles.html |newspaper=Wairarapa Times-Age |title=British immigrant made mark in Arctic world |archive-url=https://web.archive.org/web/20071007050301/http://wairarapa.co.nz/times-age/weekly/2002/ayles.html |date=November 9, 2002 |archive-date=October 7, 2007}} A 1986 survey of Canadian ice shelves found that {{convert|48|km2|abbr=on}}, a volume of {{convert|3.3|km3|abbr=on}}, of ice calved from the Milne and Ayles ice shelves between 1959 and 1974.{{cite journal |first=Martin O. |last=Jeffries |url=http://pubs.aina.ucalgary.ca/arctic/Arctic39-1-15.pdf |title=Ice Island Calvings and Ice Shelf Changes, Milne Ice Shelf and Ayles Ice Shelf, Ellesmere Island, N.W.T. |journal=Arctic |publisher=Arctic Institute of North America |volume=39 |issue=1 |date=March 1986 |access-date=December 29, 2006 |archive-date=September 28, 2019 |archive-url=https://web.archive.org/web/20190928113808/http://pubs.aina.ucalgary.ca/arctic/Arctic39-1-15.pdf |url-status=dead }}. Canada lost 94% of its overall ice shelf area between 1906 and 2015.{{cite book |last1=Mueller|first1=Derek|chapter=Changes in Canadian Arctic Ice Shelf Extent Since 1906|date=2017|title=Arctic Ice Shelves and Ice Islands|pages=109–148|editor-last=Copland|editor-first=Luke|series=Springer Polar Sciences|publisher=Springer Netherlands|language=en|doi=10.1007/978-94-024-1101-0_5|isbn=978-94-024-1101-0|last2=Copland|first2=Luke|last3=Jeffries|first3=Martin O.|editor2-last=Mueller|editor2-first=Derek}}

Ayles Ice Island

On August 13, 2005, the entire shelf broke clear from the coast of Ellesmere, forming a new ice island. It is believed to be the largest shelf breakup of its kind in Canada in over 30 years.{{cite news |url=http://environment.guardian.co.uk/climatechange/story/0,,1979937,00.html |title=Giant ice island breaks off Arctic shelf |date=December 29, 2006 |newspaper=The Guardian |access-date=October 26, 2022}} The event was registered on seismometers in northern Canada, and it was also verified via satellite imagery.

The breakup occurred over less than an hour.{{cite news |url=https://www.nytimes.com/2006/12/30/science/earth/30ice.html?hp&ex=1167454800&en=eb5d838b27550ca9&ei=5094&partner=homepage |title=Arctic Ice Shelf Broke Off Canadian Island |first=Andrew C. |last=Revkin |date=December 30, 2006 |newspaper=The New York Times |access-date=October 26, 2022}} The event was noticed by the Canadian Ice Service at the time that it occurred, but it took a further 16 months to fully reconstruct the breakup sequence from past satellite images captured by Moderate Resolution Imaging Spectroradiometer (MODIS), to determine the climatic conditions during the event, and for the event to garner public attention. The event, which has been linked to global warming, is similar to the 2002 breakup of the Larsen B Ice Shelf in Antarctica.{{cite web|url=http://news.nationalgeographic.com/news/2006/12/061229-arctic-ice.html|archive-url=https://web.archive.org/web/20070101184550/http://news.nationalgeographic.com/news/2006/12/061229-arctic-ice.html|url-status=dead|archive-date=January 1, 2007|title=Giant Ice Shelf Breaks Off in Canadian Arctic|first=Richard A. |last=Lovett|date=December 29, 2006|publisher=National Geographic|accessdate=December 30, 2011}}{{cite web|url=http://news.bbc.co.uk/2/hi/science/nature/3132074.stm|title=Ancient ice shelf breaks free in Canadian Arctic |author=|date=December 29, 2006|publisher=MSNBC|accessdate=December 30, 2011}}{{cite web|url=http://earthobservatory.nasa.gov/IOTD/view.php?id=7282|title=Ayles Ice Shelf, Ellesmere Island|first=Jeff |last=Schmaltz|date=January 6, 2007|publisher=Earth Observatory, NASA Goddard Space Flight Center|accessdate=December 30, 2011}}

Within days of the breakup, the former shelf had drifted over {{convert|50|km|abbr=on}} from Ellesmere Island before freezing into the sea ice for the winter. It was estimated in May 2007 to be between {{convert|42|and|45|m|abbr=on}} thick, on average.{{cite news

|url=http://news.bbc.co.uk/2/hi/science/nature/7022192.stm

|title=Arctic ice island breaks in half

|date=October 1, 2007

|publisher=BBC News Online

|accessdate=October 2, 2007| archiveurl= https://web.archive.org/web/20071011003823/http://news.bbc.co.uk/2/hi/science/nature/7022192.stm| archivedate= October 11, 2007 | url-status= live}}

The freed segment of the ice shelf, known as Ayles Ice Island, drifted southwesterly for two years, and in January 2007 accelerated into the open Arctic Ocean, causing concern for oil rig operators in the Beaufort Sea north of Prudhoe Bay, Alaska. In August 2007, however, the island became wedged into the Sverdrup Inlet of the Queen Elizabeth Islands. Although scientists initially thought it was likely to remain there for some time, possibly permanently,{{cite news

|url=http://news.bbc.co.uk/2/hi/science/nature/6970824.stm

|title=Vast ice island trapped in Arctic

|date=August 31, 2007

|publisher=BBC News Online

|accessdate=September 2, 2007| archiveurl= https://web.archive.org/web/20071017010326/http://news.bbc.co.uk/2/hi/science/nature/6970824.stm| archivedate= October 17, 2007 | url-status= live}} it soon afterwards broke into two parts and resumed movement.

There is concern that the ice islands may become a hazard for ships and oil platforms.{{cite web |url=https://www.cbc.ca/news/science/arctic-ice-shelf-collapse-poses-risk-expert-1.615809 |title=Arctic ice shelf collapse poses risk: expert |publisher=CBC News |date=December 28, 2006 |access-date=October 26, 2022 |url-status=live |archive-url=https://web.archive.org/web/20070101223213/http://www.cbc.ca/canada/story/2006/12/28/tech-ellesmereiceshelfcollapse-20061228.html |archive-date=January 1, 2007}}

Other ice islands

While the formation of the Ayles Ice Island received widespread attention at the time due to the availability of satellite imagery and the ability of news media and scientists to visit the island, it was by no means unprecedented. On August 14, 1946, a U.S. Air Force patrol plane flying {{convert|300|mi|abbr=on|order=flip}} north of Point Barrow spotted an ice island, dubbed T-1, which was {{convert|15|by|18|mi|abbr=on|order=flip}}. It was estimated to be from {{convert|204|to|1600|ft|abbr=on|order=flip}} thick, with sides that rose from {{convert|30|to|200|ft|abbr=on|order=flip}} above the sea surface - much larger than the Ayles Ice Island. Over the following three years, it travelled around {{convert|1500|mi|abbr=on|order=flip}} along the Beaufort Eddy, a slow-moving ocean current that flows eastward across the North Pole, then back west along the coast. In 1950, the U.S. Air Force 58th Reconnaissance Squadron was ordered to find T-1, and any other ice islands in the Arctic. In July 1950, T-2 was found, a roughly rectangular ice island estimated to be {{convert|20|by|20|mi|abbr=on|order=flip}} by dimension. In 1947, a joint U.S.-Canadian expedition had noted and photographed a fresh water sea formation in the sea off Ellesmere Island. From a photographic examination of its ridges, T-2 was discovered to be the same ice island spotted off Ellesmere Island in 1947. Later in July 1950, the U.S. Air Force found Fletcher's Ice Island, or T-3, a kidney-shaped island, {{convert|9|by|4.5|mi|abbr=on|order=flip}}. This was later occupied for brief periods in the early and mid-1950s. In August 1951, T-1 was relocated, nestled along the coast of Ellesmere Island. It is not known how long prior T-1, T-2, and T-3 had been formed, but it is believed they had calved from ice shelves on northern Ellesmere Island.{{cite magazine |title=The Mysterious Floating Islands of the Arctic |magazine=Reader's Digest |date=January 1952}} There are an estimated 80 ice islands in Canada's High Arctic, most of them part of the pack ice that covers the region.

Between August 1961 and April 1962, almost {{convert|600|km2|abbr=on}} of ice broke away from the Ward Hunt Ice Shelf.{{cite journal |first=G. |last=Hattersley-Smith |date=1963 |title=The Ward Hunt Ice Shelf: recent changes of the ice front |journal=Journal of Glaciology |volume=4 |pages=415-424}} This event was attributed to tidal and seismic events.

References

{{reflist}}

External links

{{wikinews|Ice shelf breaks free in Canadian arctic}}

  • [http://www.cbc.ca/photogallery/technology/228/ 16-image slideshow of satellite and radar images showing the breakup] (CBC News, requires Adobe Flash).
  • [https://web.archive.org/web/20070209181133/http://www.geomatics.uottawa.ca/copland/ Ayles Ice Shelf breakup images and media resources] by Dr. Luke Copland, University of Ottawa
  • [https://web.archive.org/web/20070703102359/http://www.ice.ec.gc.ca/app/WsvPageDsp.cfm?id=11835&Lang=eng Ayles Ice Shelf breakup background information] by the Canadian Ice Service
  • [https://www.cbc.ca/news/science/arctic-ice-shelf-collapse-poses-risk-expert-1.615809 Arctic ice shelf collapse poses risk: expert], CBC news, Thursday, December 28, 2006, 6:39 PM ET
  • [http://www.alertnet.org/thenews/newsdesk/N29294082.htm Huge ice shelf breaks free in Canada's far north] by Jeffrey Jones, Reuters, 29 December 2006 21:22:06 GMT
  • [http://news.bbc.co.uk/1/hi/sci/tech/6218333.stm Huge Arctic ice break discovered], BBC News, Friday, December 29, 2006, 22:52 GMT
  • [https://web.archive.org/web/20070101184550/http://news.nationalgeographic.com/news/2006/12/061229-arctic-ice.html Giant Ice Shelf Breaks Off in Canadian Arctic] by Richard A. Lovett, National Geographic News, December 29, 2006
  • [http://www.cen.ulaval.ca/warwickvincent/PDFfiles/149.pdf Ice-shelf collapse, climate change, and habitat loss in the Canadian high Arctic] F. W. Vincent, J. A. E. Gibson & M. O. Jeffries. Polar Record 37 (201): 133-142 (2001).
  • [http://news.bbc.co.uk/1/hi/sci/tech/6679321.stm Science team lands on Ice Island], BBC News, Tuesday May 22, 2007

Category:Ice shelves of Qikiqtaaluk Region