Geophysical Research Letters, Vol. 35, L20502; doi:10.1029/2008GL035417, 2008
Mass balance of the Greenland ice sheet from 1958 to 2007
E. Rignot (Department of Earth System Science, University of California, Irvine, CA, U.S.A.; Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, U.S.A.), J. E. Box (Byrd Polar Research Center, Ohio State University, Columbus, OH, U.S.A.), E. Burgess (Department of Geography, University of Utah, Salt Lake City, UT, U.S.A.), and E. Hanna (Department of Geography, University of Sheffield, Sheffield, U.K.)
We combine estimates of the surface mass balance (SMB) of the Greenland ice sheet for the years 1958 to 2007 with measurements of the temporal variability in ice discharge (D) to deduce the total ice sheet mass balance. During that time period, we find a robust correlation (R2 = 0.83) between anomalies in SMB and in D, which we use to reconstruct a continuous series of total ice sheet mass balance. We find that the ice sheet was losing 110 ± 70 Gt/yr in the 1960s, 30 ± 50 Gt/yr or near balance in the 1970s–1980s, and 97 ± 47 Gt/yr in 1996 increasing rapidly to 267 ± 38 Gt/yr in 2007. Multi-year variations in ice discharge, themselves related to variations in SMB, cause 60 ± 20% more variation in total mass balance than SMB and therefore dominate the ice sheet mass budget.
Received 21 July 2008; accepted 22 September 2008; published 22 October 2008.
Key words: glaciology, mass balance, sea level
Index Terms: 0720 Cryosphere: Glaciers; 0726 Cryosphere: Ice sheets; 0762 Cryosphere: Mass balance (1218, 1223); 1621 Global Change: Cryospheric change (0776); 1620 Global Change: Climate dynamics (0429, 3309).
Citation: (2008), Mass balance of the Greenland ice sheet from 1958 to 2007, Geophys. Res. Lett., 35, L20502, doi:10.1029/2008GL035417.
Copyright 2008 by the American Geophysical Union.
Link to abstract: http://www.agu.org/pubs/crossref/2008/2008GL035417.shtml
No comments:
Post a Comment