Environmental Science (all); Earth and Planetary Sciences (all); General Earth and Planetary Sciences; General Environmental Science
Abstract :
[en] The Greenland Ice Sheet is losing mass at accelerated rates in the 21st century, making it the largest single contributor to rising sea levels. Faster flow of outlet glaciers has substantially contributed to this loss, with the cause of speedup, and potential for future change, uncertain. Here we combine more than three decades of remotely sensed observational products of outlet glacier velocity, elevation, and front position changes over the full ice sheet. We compare decadal variability in discharge and calving front position and find that increased glacier discharge was due almost entirely to the retreat of glacier fronts, rather than inland ice sheet processes, with a remarkably consistent speedup of 4–5% per km of retreat across the ice sheet. We show that widespread retreat between 2000 and 2005 resulted in a step-increase in discharge and a switch to a new dynamic state of sustained mass loss that would persist even under a decline in surface melt.
Disciplines :
Earth sciences & physical geography
Author, co-author :
King, Michalea D. ; Byrd Polar and Climate Research Center & School of Earth Sciences, The Ohio State University, Columbus, United States
Howat, Ian M. ; Byrd Polar and Climate Research Center & School of Earth Sciences, The Ohio State University, Columbus, United States
Candela, Salvatore G.; Byrd Polar and Climate Research Center & School of Earth Sciences, The Ohio State University, Columbus, United States
Noh, Myoung J.; Byrd Polar and Climate Research Center & School of Earth Sciences, The Ohio State University, Columbus, United States
Jeong, Seongsu; Department of Earth System Science, University of California Irvine, Irvine, United States
Noël, Brice ; Université de Liège - ULiège > Département de géographie > Climatologie et Topoclimatologie ; Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht, Netherlands
van den Broeke, Michiel R. ; Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht, Netherlands
Wouters, Bert; Institute for Marine and Atmospheric Research Utrecht, Utrecht University, Utrecht, Netherlands ; Department of Geoscience and Remote Sensing, Delft University of Technology, Delft, Netherlands
Negrete, Adelaide; Byrd Polar and Climate Research Center & School of Earth Sciences, The Ohio State University, Columbus, United States
Language :
English
Title :
Dynamic ice loss from the Greenland Ice Sheet driven by sustained glacier retreat
NASA - National Aeronautics and Space Administration OSU - The Ohio State University NWO - Netherlands Organisation for Scientific Research
Funding text :
This project was supported by grants 80NSSC18K1027 and NNX13AI21A from the National Aeronautics and Space Administration and a Distinguished University Fellowship from the Ohio State University. B.W. was funded by NWO VIDI grant 016.Vidi.171.063. B.P.Y.N. was funded by NWO VENI grant VI.Veni.192.019. M.R.v.d.B. and B.P.Y.N. acknowledge funding from the Netherlands Earth System Science Center (NESSC).
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