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Smith LC, Chu VW, Yang K, et al. Efficient meltwater drainage through supraglacial streams and rivers on the southwest Greenland ice sheet. Proc Natl Acad Sci U S A. 2015;112(4):1001-6doi: 10.1073/pnas.1413024112.
Smith, L. C., Chu, V. W., Yang, K., Gleason, C. J., Pitcher, L. H., Rennermalm, A. K., Legleiter, C. J., Behar, A. E., Overstreet, B. T., Moustafa, S. E., Tedesco, M., Forster, R. R., LeWinter, A. L., Finnegan, D. C., Sheng, Y., & Balog, J. (2015). Efficient meltwater drainage through supraglacial streams and rivers on the southwest Greenland ice sheet. Proceedings of the National Academy of Sciences of the United States of America, 112(4), 1001-6. https://doi.org/10.1073/pnas.1413024112
Smith, Laurence C, et al. "Efficient meltwater drainage through supraglacial streams and rivers on the southwest Greenland ice sheet." Proceedings of the National Academy of Sciences of the United States of America vol. 112,4 (2015): 1001-6. doi: https://doi.org/10.1073/pnas.1413024112
Smith LC, Chu VW, Yang K, Gleason CJ, Pitcher LH, Rennermalm AK, Legleiter CJ, Behar AE, Overstreet BT, Moustafa SE, Tedesco M, Forster RR, LeWinter AL, Finnegan DC, Sheng Y, Balog J. Efficient meltwater drainage through supraglacial streams and rivers on the southwest Greenland ice sheet. Proc Natl Acad Sci U S A. 2015 Jan 27;112(4):1001-6. doi: 10.1073/pnas.1413024112. Epub 2015 Jan 12. PMID: 25583477; PMCID: PMC4313838.
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Proc Natl Acad Sci U S A. 2015 Jan 27;112(4):1001-6. doi: 10.1073/pnas.1413024112. Epub 2015 Jan 12.

Efficient meltwater drainage through supraglacial streams and rivers on the southwest Greenland ice sheet.

Proceedings of the National Academy of Sciences of the United States of America

Laurence C Smith, Vena W Chu, Kang Yang, Colin J Gleason, Lincoln H Pitcher, Asa K Rennermalm, Carl J Legleiter, Alberto E Behar, Brandon T Overstreet, Samiah E Moustafa, Marco Tedesco, Richard R Forster, Adam L LeWinter, David C Finnegan, Yongwei Sheng, James Balog

Affiliations

  1. Department of Geography, University of California, Los Angeles, CA 90095; [email protected].
  2. Department of Geography, University of California, Los Angeles, CA 90095;
  3. Department of Geography, Rutgers University, Piscataway, NJ 08854;
  4. Department of Geography, University of Wyoming, Laramie, WY 82071;
  5. NASA Jet Propulsion Laboratory, Pasadena, CA 91109;
  6. Department of Earth and Atmospheric Science, The City College of New York, NY, 10031;
  7. Department of Geography, University of Utah, Salt Lake City, UT 84112;
  8. U.S. Army Cold Regions Research & Engineering Laboratory, Hanover, NH 03755; and.
  9. Earth Vision Trust, Boulder, CO 80304.

PMID: 25583477 PMCID: PMC4313838 DOI: 10.1073/pnas.1413024112

Abstract

Thermally incised meltwater channels that flow each summer across melt-prone surfaces of the Greenland ice sheet have received little direct study. We use high-resolution WorldView-1/2 satellite mapping and in situ measurements to characterize supraglacial water storage, drainage pattern, and discharge across 6,812 km(2) of southwest Greenland in July 2012, after a record melt event. Efficient surface drainage was routed through 523 high-order stream/river channel networks, all of which terminated in moulins before reaching the ice edge. Low surface water storage (3.6 ± 0.9 cm), negligible impoundment by supraglacial lakes or topographic depressions, and high discharge to moulins (2.54-2.81 cm⋅d(-1)) indicate that the surface drainage system conveyed its own storage volume every <2 d to the bed. Moulin discharges mapped inside ∼52% of the source ice watershed for Isortoq, a major proglacial river, totaled ∼41-98% of observed proglacial discharge, highlighting the importance of supraglacial river drainage to true outflow from the ice edge. However, Isortoq discharges tended lower than runoff simulations from the Modèle Atmosphérique Régional (MAR) regional climate model (0.056-0.112 km(3)⋅d(-1) vs. ∼0.103 km(3)⋅d(-1)), and when integrated over the melt season, totaled just 37-75% of MAR, suggesting nontrivial subglacial water storage even in this melt-prone region of the ice sheet. We conclude that (i) the interior surface of the ice sheet can be efficiently drained under optimal conditions, (ii) that digital elevation models alone cannot fully describe supraglacial drainage and its connection to subglacial systems, and (iii) that predicting outflow from climate models alone, without recognition of subglacial processes, may overestimate true meltwater export from the ice sheet to the ocean.

Keywords: Greenland ice sheet; mass balance; meltwater runoff; remote sensing; supraglacial hydrology

References

  1. Science. 2005 Oct 21;310(5747):456-60 - PubMed
  2. Science. 2002 Jul 12;297(5579):218-22 - PubMed
  3. Nature. 2010 Dec 9;468(7325):803-6 - PubMed
  4. Nature. 2011 Jan 27;469(7331):521-4 - PubMed
  5. Nature. 2014 Oct 2;514(7520):80-3 - PubMed
  6. Science. 2013 Aug 30;341(6149):997-9 - PubMed
  7. Science. 2008 May 9;320(5877):778-81 - PubMed
  8. Science. 2009 Nov 13;326(5955):984-6 - PubMed

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