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Noël B, Jakobs CL, van Pelt WJJ, Lhermitte S, Wouters B, Kohler J, Hagen JO, Luks B, Reijmer CH, van de Berg WJ, van den Broeke MR. Low elevation of Svalbard glaciers drives high mass loss variability. Nat Commun 2020; 11:4597. [PMID: 32929066 PMCID: PMC7490702 DOI: 10.1038/s41467-020-18356-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 08/13/2020] [Indexed: 11/10/2022] Open
Abstract
Compared to other Arctic ice masses, Svalbard glaciers are low-elevated with flat interior accumulation areas, resulting in a marked peak in their current hypsometry (area-elevation distribution) at ~450 m above sea level. Since summer melt consistently exceeds winter snowfall, these low-lying glaciers can only survive by refreezing a considerable fraction of surface melt and rain in the porous firn layer covering their accumulation zones. We use a high-resolution climate model to show that modest atmospheric warming in the mid-1980s forced the firn zone to retreat upward by ~100 m to coincide with the hypsometry peak. This led to a rapid areal reduction of firn cover available for refreezing, and strongly increased runoff from dark, bare ice areas, amplifying mass loss from all elevations. As the firn line fluctuates around the hypsometry peak in the current climate, Svalbard glaciers will continue to lose mass and show high sensitivity to temperature perturbations. Svalbard glaciers are among the lowest ice masses in the Arctic, with a peak in glacier area below 450 m elevation. Using a high-resolution climate model, here the authors show that a modest warming in the mid-1980s propagated meltwater runoff above the glacier area peak, amplifying Svalbard mass loss from all elevations.
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Affiliation(s)
- Brice Noël
- Institute for Marine and Atmospheric research Utrecht, Utrecht University, 3584 CC, Utrecht, Netherlands.
| | - C L Jakobs
- Institute for Marine and Atmospheric research Utrecht, Utrecht University, 3584 CC, Utrecht, Netherlands
| | - W J J van Pelt
- Department of Earth Sciences, Uppsala University, SE 75236, Uppsala, Sweden
| | - S Lhermitte
- Department of Geoscience & Remote Sensing, Delft University of Technology, 2600 AA, Delft, Netherlands
| | - B Wouters
- Institute for Marine and Atmospheric research Utrecht, Utrecht University, 3584 CC, Utrecht, Netherlands.,Department of Geoscience & Remote Sensing, Delft University of Technology, 2600 AA, Delft, Netherlands
| | - J Kohler
- Norwegian Polar Institute, N-9296, Tromsø, Norway
| | - J O Hagen
- Department of Geosciences, University of Oslo, 0371, Oslo, Norway
| | - B Luks
- Institute of Geophysics, Polish Academy of Sciences, 01-452, Warsaw, Poland
| | - C H Reijmer
- Institute for Marine and Atmospheric research Utrecht, Utrecht University, 3584 CC, Utrecht, Netherlands
| | - W J van de Berg
- Institute for Marine and Atmospheric research Utrecht, Utrecht University, 3584 CC, Utrecht, Netherlands
| | - M R van den Broeke
- Institute for Marine and Atmospheric research Utrecht, Utrecht University, 3584 CC, Utrecht, Netherlands
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van de Wal RSW, Boot W, van den Broeke MR, Smeets CJPP, Reijmer CH, Donker JJA, Oerlemans J. Large and rapid melt-induced velocity changes in the ablation zone of the Greenland Ice Sheet. Science 2008; 321:111-3. [PMID: 18599784 DOI: 10.1126/science.1158540] [Citation(s) in RCA: 258] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Continuous Global Positioning System observations reveal rapid and large ice velocity fluctuations in the western ablation zone of the Greenland Ice Sheet. Within days, ice velocity reacts to increased meltwater production and increases by a factor of 4. Such a response is much stronger and much faster than previously reported. Over a longer period of 17 years, annual ice velocities have decreased slightly, which suggests that the englacial hydraulic system adjusts constantly to the variable meltwater input, which results in a more or less constant ice flux over the years. The positive-feedback mechanism between melt rate and ice velocity appears to be a seasonal process that may have only a limited effect on the response of the ice sheet to climate warming over the next decades.
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Affiliation(s)
- R S W van de Wal
- Institute for Marine and Atmospheric research Utrecht, Utrecht University, Netherlands.
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van de Berg WJ, van den Broeke MR, Reijmer CH, van Meijgaard E. Reassessment of the Antarctic surface mass balance using calibrated output of a regional atmospheric climate model. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006495] [Citation(s) in RCA: 225] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Reijmer CH. Evaluation of temperature and wind over Antarctica in a Regional Atmospheric Climate Model using 1 year of automatic weather station data and upper air observations. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2004jd005234] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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