Mapping Ice Melting
April 6, 2009
This post on mapping ice melting in Antarctica, which is part of an ongoing mapping memory project by a bricoleuse, is updated beyond its first publication date, April 6, 2009, as new satellite images become available from the NASA, European Space Agency, British Antarctic Survey, Arctic Council etc. The post includes a time line of melting ice, a customized Google Map and a webliography. Effort is made to use the semantic web to its fullest through attentive folksonomy.
The most recent update:
Geoscientist Jianli Chen (Chen et al 2009-11-22) used remote-sensing data from GRACE’s two satellites to track climate change and to quantify Antarctic ice elevations and ice motion and have concluded that the Eastern Antarctic ice sheet, the biggest ice sheet on earth, which was considered to be inviolate and stable, is actually experiencing significant ice loss, c. 57 gigatonnes a year since c. 2006. Eastern Antarctic ice sheet is home to 90% of Earth’s solid fresh water. West Antarctica is losing c. 132 gigatonnes of ice per year. GRACE allows for more accurate quantification of Antarctic ice-sheet mass balance and its contribution to global sea-level rise. A gigatonne is one billion metric tons, or more than 2.2 trillion pounds.
Mapping Ice Melt @ googlemap: http://snurl.com/h3l9b wordpress: http://snurl.com/h3leq http://snurl.com/h3m09 by a concerned bricoleuse using open data and the tools the semantic web and web 2.0 as part of a mapping communal memory series. This post will continue to be updated as new satellite images become available from the European Space Agency, British Antarctic Survey, Arctic Council etc. The post includes a time line of melting ice, a customized Google Map and a webliography. Effort is made to use the semantic web to its fullest through attentive folksonomy. The Wilkins Ice Shelf, a plate of floating ice on the western Antarctic Peninsula connecting to two islands, Charcot and Latady was very stable since the 1930s but began retreating in the 1990s. Since the late 1950s average temperatures have risen by half a degree Celsius a decade (ESA 2007) making the continent one of the fastest warming places on earth. Six of its ice shelves
University of Colorado’s National Snow and Ice Data Center, explained (2008-11-26),
“Ice thickness, its spatial extent, and the fraction of open water within the ice pack can vary rapidly and profoundly in response to weather and climate. Sea ice typically covers about 14 to 16 million square kilometers in late winter in the Arctic and 17 to 20 million square kilometers in the Antarctic Southern Ocean. On average, the seasonal decrease is much larger in the Antarctic, with only about three to four million square kilometers remaining at summer’s end, compared to approximately seven million square kilometers in the Arctic. Over the past several years, Arctic minima have been only four to six million square kilometers. [Maps of late winter and late summer ice cover in the the Arctic and Antarctica] … The interaction between sea ice loss and ice shelf retreat merits careful study because many ice shelves are fed by glaciers. When an ice shelf disintegrates, the glacier feeding it often accelerates. Because glacier acceleration introduces a new ice mass into the ocean, it can raise ocean level. So while sea ice melt does not directly lead to sea level rise, it could contribute to other processes that do, both in the Arctic and the Antarctic. Glacier acceleration has already been observed on the Antarctic Peninsula, although the accelerating glaciers in that region have so far had a negligible effect on ocean level NASA. 2009-04-21).”
Scientists commonly divide the sea ice pack around Antarctica into five sectors: the Weddell Sea, the Indian Ocean, the western Pacific Ocean, the Ross Sea, and the Bellingshausen/Amundsen seas. In some sectors, it is common for nearly all the sea ice to melt in the summer… [U]nlike the Arctic, where the downward trend is consistent in all sectors, in all months, and in all seasons, the Antarctic picture is more complex. Based on data from 1979-2006, the annual trend for four of the five individual sectors was a very small positive one, but only in the Ross Sea was the increase statistically significant (greater than the natural year-to-year variability). On the other hand, ice extent decreased in the Bellingshausen/Amundsen Sea sector during the same period NASA. 2009-04-21).”
The Wilkins Ice Shelf, a plate of floating ice on the western Antarctic Peninsula connecting to two islands, Charcot and Latady was very stable since the 1930s but began retreating in the 1990s. Since the late 1950s average temperatures have risen by half a degree Celsius a decade (ESA 2007) making the continent one of the fastest warming places on earth. Six of its ice shelves already completely collapsed: Prince Gustav Channel, Larsen Inlet, Larsen A, Larsen B, Wordie, Muller and the Jones Ice Shelf (BBC 2009-04-05).
The Wilkins Ice Shelf is monitored by the European Space Agency and the British Antarctic Survey. In 2008 a c. 400 km² broke off from the Wilkins Ice Shelf. The bridge between Charcot and Latady islands was narrowed down by May, 2008 to just 2.7 km.
In early April 2009 the thin ice bridge, which served to protect thousands of kilometres of Wilkins Ice Shelf from further break-up, snapped.
See NASA April 7, 2009 images and description
2009-04-07 “The Obama administration on Monday called for enhanced protection of the Earth’s polar regions, proposing mandatory limits on Antarctic tourism and urging increased research in Antarctica and in the Arctic. Opening a conference of parties to the Antarctic Treaty, Secretary of State Hillary Rodham Clinton said the recent collapse of an Antarctic ice bridge was a stark reminder that the poles were gravely threatened by climate change and human activity. She said the treaty, which also bans military use of the continent, could be a model for improved cooperation and coordination in the Arctic, which is not governed by a similar pact (AP 2009-04-07).”
|The Wilkins Ice Shelf may be on the brink of breaking away as an ice bridge between Charcot and Latady Islands has just ruptured.|
Professor David Vaughan, a glaciologist with the British Antarctic Survey said the breaking of the bridge had been anticipated for awhile and the collapse of the Wilkins Ice Shelf is likely to follow. “The fact that it’s retreating and now has lost connection with one of its islands is really a strong indication that the warming on the Antarctic is having an effect on yet another ice shelf.” more | (BBC 2009-04-05)
Timeline of melting ice in Antartica
1900 The ice shelves across northern Ellesmere Island were first observed and noted by western scientists (“discovered”). In 1900 the total area of these ice shelves was c. 10,000 sq km. (Luke Copeland University of Ottawa).
1956-1993 The Müller Ice Shelf was 80 sq km in 1956 and 49 sq km by 1993 (Ward 1995).
1970s Rothera Research Station was opened 67° 34’ S, 68 ° 08’ W, Rothera Point, Adelaide Island, Antartica.
1970s The Jones Ice Shelf was 25 sq km in 1947 and had disappeared by 2003. “In recent decades, several ice shelves along the Antarctic Peninsula have diminished in size as a result of climate warming. Using aerial photographic, satellite and survey data we document a similar retreat of Jones Ice Shelf, which was another small ice shelf on the west coast of the Antarctic Peninsula. This ice shelf was roughly stable between 1947 and 1969, but in the early 1970s it began to retreat and had completely disappeared by early 2003. Jones Ice Shelf has two ice fronts only a few kilometres apart and its retreat provides a unique opportunity to examine how different ice fronts retreat when subjected to similar climate forcing. We mapped the retreat of both the east and west ice fronts of Jones Ice Shelf and found that, although individual episodes of retreat may be related to particularly warm summers, the overall progress of retreat of the two ice fronts has been rather different. This suggests that in this case the course of retreat is controlled by the geometry of the embayment and location of pinning points as well as climatic events (Fox and Vaughan 2005).”
1995 Larsen A broke off in 1995.
2002 A piece of ice that was sheered away from Larsen B roughly the size of Luxembourg represented the biggest for 10,000 years since the Ice Age. […] “In March 2002, scientists announced the Larsen B ice shelf on the Antarctic Peninsula had entered a phase of rapid break-up with more than 50 billion tons of ice spilling into the Weddell Sea to form thousands of massive icebergs. It had been known for many years that the ice shelf was thinning and in retreat but the speed of its final collapse astonished scientists. It took just 35 days for the Larsen B ice shelf to fall away completely after a Nasa satellite detected the first ruptures in the 1,255 square miles of ice at the end of January 2002.”(Connor 2005-08-04)
2002-03 Gravity Recovery and Climate Experiment5 (GRACE) are twin satellites launched in March 2002, capable of making detailed measurements of Earth’s gravity field which will lead to discoveries about gravity and Earth’s natural systems. These discoveries could have far-reaching benefits to society and the world’s population. Grace is a partnership between NASA and the German Aerospace Center, DLR. JPL developed the twin Grace satellites. The University of Texas Center for Space Research in Austin has overall Grace mission responsibility.
2005-08-13 “On August 13, 2005, almost the entire Ayles Ice Shelf calved from the northern edge of Ellesmere Island. This reduced the remaining ice shelves there from 6 to 5, and continues a trend of dramatic loss of these ice shelves over the past century. Since 1900, approximately 90% of the Ellesmere Island ice shelves have calved and floated away. This is a one-way process as there is insufficient new ice formation to replace the ice that has been lost. The Ayles calving event was the largest in at least the last 25 years; a total of 87.1 sq km (33.6 sq miles) of ice was lost in this event, of which the largest piece was 66.4 sq km (25.6 sq. miles) in area. This piece is equivalent in size to approximately 11,000 football fields or a little larger than the City of Manhattan. Please note that some media stories have incorrectly stated the area as 41 sq. miles due to an improper conversion from sq. km” – (Ayles Ice Shelf – Dr. Luke Copland)
2007 In 2007 Dr. Luke Copland, an assistant professor of geography at the University of Ottawa, noted that “there have been many breakups of ice shelves across northern Ellesmere Island over the last century so. When these ice shelves were first discovered in about 1900, they were a total of about 10,000 sq km in area. Today they have reduced in size by about 90%, to about 1000 sq km in area. The Ayles Ice Shelf loss was the largest breakup in at least 25 years, but it is part of the long-term trend of loss over the last century. The important point to note with all of these losses is that they are essentially permanent. There is no longer enough glacier ice flowing off the land to replace the ice that is being calved into the ocean. Hence these 3000+ year old shelves are now gone forever.” For more info on Dr Copland’s work visit
2007 Mauri Pelto, a glaciologist at Nichols College published an article on the calving of the Ayles Ice Shelf in the Arctic Circle.
2008-03-28 The European Space Agency captured these images of the break up of the Wilkins Ice Shelf:
2009-04-28 European Space Agency satellite images of the shelf show that in the third week in April 2009 alone, 370 sq km of the northern ice front of the Wilkins Ice Shelf shattered into its first mass of icebergs released into the ocean,” Angelika Humbert, glaciologist at the University of Muenster in Germany, reported to Reuters that “about 700 sq km of ice – bigger than Singapore or Bahrain and almost the size of New York – has broken off the Wilkins this month and shattered into a mass of icebergs. [This is the most recent in a series of about 10 ice shelves on the Antarctic Peninsula to retreat in a trend linked by the UN Climate Panel to global warming. The new icebergs added to 330 sq kms of ice that broke up earlier this month with the shattering of an ice bridge apparently pinning the Wilkins in place between Charcot island and the Antarctic Peninsula. Nine other shelves – ice floating on the sea and linked to the coast – have receded or collapsed around the Antarctic peninsula in the past 50 years, often abruptly like the Larsen A in 1995 or the Larsen B in 2002. [Humbert had previously warned that once the ice bridge between Charcot and Latady islands off the Antarctic Peninsula collapsed (which happened earlier in April 2009) the Wilkins Ice Shelf could lose a total of 800 to 3,000 sq kms of area]. The Wilkins shelf has already shrunk by about a third from its original 16,000 sq kms when first spotted decades ago. [Because of the thickness of the ice on the Wilkens Ice Shelf it was estimated that it took at least hundreds of years to form.] (Reuters 2009-04-28) (Reuters 2009-04-28).”
2009-08-14 “Researchers at the University of Leeds, writing in the journal Geophysical Research Letters, said the Pine Island Glacier in West Antarctica is thinning at a rate of up to 16 metres a year and has lowered as much as 90 metres in the last decade. At its current rate of thinning, the glacier could disappear in a century. Previous predictions, based on the glacier’s rate of decline a decade ago, said the glacier would likely disappear in 600 years. The Pine Island Glacier is the largest glacier in West Antarctica, and at 175,000 square kilometres is roughly the size of the province of New Brunswick and the island of Newfoundland combined (CBC 2009-08-14).” “One of Antarctica’s greatest glaciers is thinning so quickly it could disappear within 100 years. This is 500 years sooner than previously estimated and jeopardises a volume of ice that could raise global sea levels by around 25cm. British Antarctic Survey fieldcamp on Pine Island Glacier Researchers reported just eight years ago that Pine Island Glacier in West Antarctica could be lost within 600 years, but now they say satellite data covering a longer period of time means they are able to make a more accurate estimate. Research led by Professor Duncan Wingham of University College London suggests that the rate at which the glacier is thinning has accelerated and spread inland. Wingham and his team calculate that the central ‘trunk’ of the glacier lost four times as much ice in 2006 than it did in 1995: around 10.2 cubic kilometres compared with 2.6 cubic kilometres (Planet Earth 2009-08-14).”
2009-11-22 Geoscientist Jianli Chen (Chen et al 2009-11-22) used remote-sensing data from GRACE’s two satellites to track climate change and to quantify Antarctic ice elevations and ice motion and have concluded that the Eastern Antarctic ice sheet, the biggest ice sheet on earth, which was considered to be inviolate and stable, is actually experiencing significant ice loss, c. 57 gigatonnes a year since c. 2006. Eastern Antarctic ice sheet is home to 90% of Earth’s solid fresh water. West Antarctica is losing c. 132 gigatonnes of ice per year. GRACE allows for more accurate quantification of Antarctic ice-sheet mass balance and its contribution to global sea-level rise. A gigatonne is one billion metric tons, or more than 2.2 trillion pounds.
Key words: polar regions ; Antarctica ; Atmosphere cryosphere interaction ; Ayles Ice Shelf; Glacier retreat ; Dynamical climatology ; Space remote sensing ; Antarctic Peninsula ; warming ; climate modification ; imagery ; Landsat satellite ; Satellite observation ; aerial photography ; Aerial survey ; monitoring ; Glacier variation ; Ice shelf ; ice caps ; Polar Cap ; Antarctica, climate change, global sea level, global warming, ice flow, Larsen Ice Shelf, melting, South Pole
This article has the best map of Arctic Ice shelves Ellesmere Island: http://www.ice.ec.gc.ca/content_contenu/2007coplandweir.pdf
Webliography and Bibliography
AP. 2009. “U.S. Seeks Protection of Polar Areas.” New York Times.
BBC. 2009-04-05. “Ice bridge ruptures in Antarctic
Connor, Steve. 2005-08-04. “Ice shelf collapse was biggest for 10,000 years since Ice Age.” The London Independent.
European Space Agency. 2007-03-02. “Earth from Space: Larsen-B Ice Shelf on thin ice.”
European Space Agency. 2008-03-28. “Earth from Space: Further break-up of Antarctic ice shelf”
European Space Agency. 2008-06-13. “Even the Antarctic winter cannot protect Wilkins Ice Shelf.”
European Space Agency. 2009-04-03. “Collapse of the ice bridge supporting Wilkins Ice Shelf appears imminent.”
Fox, Adrian J.; Vaughan, David G.. 2005. “The retreat of Jones Ice Shelf, Antarctic Peninsula.” Journal of Glaciology. 51 (175). 555-560
NASA. 2009-04-21. Sea Ice Ebbs and Flows.
NASA. 2009-04-21. “Sea Ice Ebbs and Flows: Antarctica.”
Planet Earth. 2009-08-14. Pine Island glacier may disappear within 100 years.”
Reuters. 2009-04-28. “New York-sized ice shelf collapses off Antarctica.” The Independent.
See also NASA webliography
Cavalieri, D. J., and C. L. Parkinson (2008). Antarctic sea ice variability and trends, 1979–2006, Journal of Geophysical Research Oceans. 113, C07004.
NASA. 2009-08-12. “Satellites Unlock Secret to Northern India’s Vanishing Water.” NASA Jet Propulsion Laboratory. http://www.jpl.nasa.gov/news/news.cfm?release=2009-124
Chen, J. L.; Wilson, C. R.; Blankenship, D.; Tapley, B. D. 2009-11-22. “Accelerated Antarctic ice loss from satellite gravity measurements.” Nature Geoscience. pp. 859-862. deep internet, Cl@$ed
NASA. 2009-11-24. “The Big Thaw? NASA Satellites Detect Unexpected Ice Loss in East Antarctica.” http://www.nasa.gov/topics/earth/features/grace20091124.html
Comiso, J.C., Parkinson, C.L., Gersten, R., Stock, L. (2008). Accelerated decline in the Arctic sea ice cover. Geophysical Research Letters. 35, L01703.
de la Mare, W.K. (1997). Abrupt mid-twentieth-century decline in Antarctic sea-ice extent from whaling records. Nature. 389, 57-60.
Goosse, H., Lefebvre, W., de Montety, A., Crespin, E., and Orsi, A.H. (2008). Consistent past half-century trends in the atmosphere, the sea ice and the ocean at high southern latitudes. Climate Dynamics.
Intergovernmental Panel on Climate Change. (2007). Summary for Policymakers. In:Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the
Intergovernmental Panel on Climate Change, M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden, and C.E. Hanson, Eds., Cambridge, UK: Cambridge University Press, pp. 7-22.
Mahoney, A.R., Barry, R.G., Smolyanitsky, V., Fetterer, F. (2008). Observed sea ice extent in the Russian Arctic, 1933–2006. Journal of Geophysical Research. 113, C11005.
Meier, W.N., Stroeve, J., Fetterer, F. (2007). Whither Arctic sea ice? A clear signal of decline regionally, seasonally, and extending beyond the satellite record. Annals of Glaciology. 46(1), 428-434.
National Snow and Ice Data Center:
All About Sea Ice. Accessed March 6, 2009.
Arctic Sea Ice Down to Second-Lowest Extent; Likely Record-Low Volume. Accessed March 6, 2009.
Arctic Sea Ice News and Analysis. Accessed March 6, 2009.
Frequently Asked Questions about Sea Ice. Accessed February 4, 2009.
State of the Cryosphere. Accessed 2009-02-04.
Overland, J.E., Spillane, M.C., Percival, D.B., Wang, M., Mofjeld, H.O. (2004). Seasonal and regional variation of Pan-Arctic surface air temperature over the instrumental record. American Meteorological Society. 17(17), 3263-3282.
Parkinson, C.L. (1997). Earth from Above. University Science Books. Sausalito, California.
Parkinson, C.L. (2000). Recent trend reversals in arctic sea ice extents: possible connection to the north Atlantic oscillation. Polar Geography. 31(1-2), 3-14.
Parkinson, C.L., Cavalieri, D.J. (2008). Arctic sea ice variability and trends, 1979-2006. Journal of Geophysical Research. 113, C07003.
Raphael, M.N. (2007). The influence of atmospheric zonal wave three on Antarctic sea ice variability. Journal of Geophysical Research. 112, D12112.
Scambos, T.A., Bohlander, J.A., Shuman, C.A., Skvarca, P. (2004). Glacier acceleration and thinning after ice shelf collapse in the Larsen B embayment, Antarctica.Geophysical Research Letters. 31, L18402.
Schiermeier, Q. (2006). A sea change. Nature. 439, 256-260.
Serreze, M.C., Holland, M.K., Stroeve, J. (2007). Perspectives on the Arctic’s shrinking sea-ice cover. Science. 315(5818), 1533-1536.
Steig, E.J., Schneider, D.P., Rutherford, S.D., Mann, M.E., Comiso, J.C., Shindell, D.T. (2009). Warming of the Antarctic ice-sheet surface since the 1957 International Geophysical Year. Nature. 457, 459-463.
Yuan, X. (2004). ENSO-related impacts on Antarctic sea ice: a synthesis of phenomenon and mechanisms. Antarctic Science. 16(4), 415-425.
Lindsey, R. 2008-12-04.New Cracks in the Wilkins Ice Shelf. Earth Observatory. Accessed 2009-08-12.
Riebeek, H. 2009-04-08. Wilkins Ice Bridge Collapse. Earth Observatory. Accessed 2009-08-12.
Scott, M. 2008-03-26. Disintegration: Antarctic Warming Claims Another Ice Shelf. Earth Observatory. Accessed 2009-08-12.
State of the Cryosphere. 2008-11-14.Ice Shelves. National Snow and Ice Data Center. Accessed August 12, 2009.
NASA image created by Jesse Allen, using data obtained from the Goddard Level 1 and Atmospheric Archive and Distribution System (LAADS). Caption by Michon Scott based on image interpretation by Ted Scambos, National Snow and Ice Data Center.
Lindsey, R. (2008, December 4). New Cracks in the Wilkins Ice Shelf. Earth Observatory. Accessed August 12, 2009.
Riebeek, H. (2009, April 8). Wilkins Ice Bridge Collapse. Earth Observatory. Accessed August 12, 2009.
Scott, M. (2008,March 26). Disintegration: Antarctic Warming Claims Another Ice Shelf. Earth Observatory. Accessed August 12, 2009.
State of the Cryosphere. (2008, November 14). Ice Shelves. National Snow and Ice Data Center. Accessed August 12, 2009.
NASA image created by Jesse Allen, using data obtained from the Goddard Level 1 and Atmospheric Archive and Distribution System (LAADS). Caption by Michon Scott based on image interpretation by Ted Scambos, National Snow and Ice Data Center