One of Greenland’s largest glaciers has suffered an abrupt breakup and retreat, losing a chunk approximately one-eighth the size of Manhattan Island.
This is an extended article following up on a previous summary provided on Planetsave.
The Jakobshavn Isbrae, also known as the Jakobshavn Glacier, lost a 7 square kilometre (2.7 square mile) section of the glacier that broke up over July 6 and 7. The front of the glacier which meets the ocean, known as the calving front, retreated nearly 1.5 kilometres (a mile) in a single day and is now further inland than at any other observed time.
“While there have been ice breakouts of this magnitude from Jakonbshavn and other glaciers in the past, this event is unusual because it occurs on the heels of a warm winter that saw no sea ice form in the surrounding bay,” said Thomas Wagner, cryospheric program scientist at NASA Headquarters.
“While the exact relationship between these events is being determined, it lends credence to the theory that warming of the oceans is responsible for the ice loss observed throughout Greenland and Antarctica,” Wagner added.
Imagery of the breakup came from several satellites including NASA’s Landsat, Terra and Aqua, which provided a broad view of ice changes and then in the days leading up to the breakup the NASA team received images from DigitalGlobe’s WorldView 2 satellite which showed massive cracks and crevasses forming in the glacier.
Greenland and Antarctica have received a lot of redirected focus over the past few years after concerns suggesting that both large ice masses were contributing heavily to global sea level rise.
Research teams led by Ian Howat of the Byrd Polar Research Center at Ohio State University and Paul Morin, director of the Antarctic Geospatial Information Center at the University of Minnesota have been focusing their attention on changes in the Greenland ice sheet and its outlet glaciers, receiving near-daily satellite images from the Jakobshavn, Kangerlugssuaq, and Helheim glaciers and weekly updates on smaller outlet glaciers.
Records show that the Jakobshavn glacier has retreated more than 45 kilometres (27 miles) over the past 160 years. However 10 kilometres of that retreat (6 miles) has taken place in the last decade; a staggering increase.
Scientists believe that as much as ten percent of all ice lost from Greenland is coming from the Jakobshavn glacier, which they also believe is the largest contributor to sea level rise in the northern hemisphere.
Image Source: DigitalGlobe