image: Tidewater glacier in Southeast Greenland, summer of 2018. view more
Credit: Image courtesy of Eric Rignot.
Researchers report changes in the mass of the Greenland Ice Sheet over the past 46 years. Greenland has been losing ice over the past several decades, but quantifying changes in ice mass prior to the early 1990s is challenging due to a shortage of data. Eric Rignot and colleagues reconstructed the net mass changes of the Greenland Ice Sheet from 1972 to 2018 by combining data on ice velocity, thickness, and surface elevation for 260 glacial drainage basins with advanced atmospheric climate models. The authors used climate models to estimate rates of ice accumulation, sublimation, and melting at the glacier surface, and velocity and thickness data to calculate the rate of ice discharge into the ocean. Greenland switched from gaining an average of 47 Gt per year of ice in the 1970s to losing an average of 50 Gt per year in the 1980s. Since then, the rate of ice loss has increased six-fold, to approximately 290 Gt per year during 2010-2018. The authors estimated that since 1972, ice loss from Greenland has contributed to a 13.7 mm rise in global sea level, with the largest contributions coming from northwest, southeast, and central-west Greenland. These regions are likely to dominate the ice sheet mass balance in the immediate future, but areas in the north, where buttressing floating ice shelves are disappearing, will ultimately be of the greatest importance to sea level change, according to the authors.
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Article #19-04242: "Forty-six years of Greenland Ice Sheet mass balance from 1972 to 2018," by Jeremie Mouginot et al.
MEDIA CONTACT: Eric Rignot, University of California, Irvine, CA; tel: 949-824-3739, 818-653-2531; e-mail: <erignot@uci.edu>
Journal
Proceedings of the National Academy of Sciences