Zachariae, a gigantic Greenland glacier that contains enough water to increase sea levels by at least 18 inch globally, is being dislodged by a stabilizing sill. It is losing 5 billion tonnes of mass annually, which is roughly the same weight as 60 million adult human beings each year. According to scientists from NASA Jet Propulsion and the University of California Irvine (UCI), Zachariae Isstrom has entered an ‘accelerated retreat’ phase in 2012,. Their findings were published in Science. Satellite photograph taken August 30, 2014, of Zachariae Isstrom and Nioghalvfjerdsfjorden, two huge glaciers in northeast Greenland. Landsat. Credit: NASA/USGS. Lead author Jeremie Muginot is an associate scientist in UCI’s Department of Earth System Science. He stated that North Greenland’s glaciers are rapidly changing. Over the past few years, Zachariae’s dynamics and shape have dramatically changed. “The glacier is currently breaking down and calving large volumes of icebergs in the ocean. This will cause rising sea levels over the next decades.” Data from NASA’s Operation IceBridge, an aerial survey that monitors changes in polar ice, and satellite-based observations collected by various space agencies (NASA CSA DLR, JAXA ESA, ESA, and ASI), were used by scientists from the Polar Space Task Group. Ultra-sensitive radar sounders, laser profiling and gravimeters, along with radar and optical images from space provide detailed information on Earth’s polar regions. Drilling of the Zachariae Isstrom’s bottom The scientists found that the oceans are warming and melting more ice sheets, which is causing the Isstrom to recede rapidly. Dr. Mouginot stated that “Ocean heating has probably played a significant role in triggering [*]retreat,” but more oceanographic data is needed to assess the future of this crucial sector of Greenland. Prof. Rignot stands aboard the 294-ton Cape Race from which he and colleagues measured Greenland’s melting glaciers during summer 2014.. Image Credit: Maria Stenzel/for UCI. Eric Rignot (Chancellor’s Professor Earth System Science at UCI), said that Zachariae Isstrom was being hit both from the top and bottom. The top of the glacier is melting away as a result of decades of steadily increasing air temperatures, while its underside is compromised by currents carrying warmer ocean water, and the glacier is now breaking away into bits and pieces and retreating into deeper ground.” Another huge glacier also melting rapidly Nioghalvfjerdsfjorden, another giant glacier (Zachariae Isstrom’s neighbor), is also melting fast, but is receding at a slower pace because an inland hill is protecting it. These two huge glaciers form 12% Greenland’s Ice Sheet and could cause global sea level rises of over 39 inches if they collapse completely. Professor Rignot said: “We wondered a while back about what would happen to sea levels if Earth’s main glaciers started retreating. It’s no longer necessary to be concerned. For several decades, scientists have been able directly to observe the effects of climate change on polar glaciers. NASA’s Cryospheric Sciences Program is funding the study. Citation: “Fast Retreat of Zachariae Isstrom in northeast Greenland,” J. Mouginot and E. Rignot. B. Scheuchl. I. Fenty. A. Khazendar. M. Morlighem. A. Buzzi. J. Paden. Science aac7111. Published online 12 November 2015. DOI: 10.1126/science.aac7111. UCI Video: Greenland Expedition with Isabella Velicogna and Prof. Rignot – The ‘time bombs’ effect of global warming.
The collapse of the giant Greenland glacier could cause sea level rise by 18 inches.
