Abstract
The contribution of the Greenland and West Antarctic ice sheets to sea level has increased in recent decades, largely owing to the thinning and retreat of outlet glaciers and ice streams1,2,3,4. This dynamic loss is a serious concern, with some modelling studies suggesting that the collapse of a major ice sheet could be imminent5,6 or potentially underway7 in West Antarctica, but others predicting a more limited response8. A major problem is that observations used to initialize and calibrate models typically span only a few decades, and, at the ice-sheet scale, it is unclear how the entire drainage network of ice streams evolves over longer timescales. This represents one of the largest sources of uncertainty when predicting the contributions of ice sheets to sea-level rise8,9,10. A key question is whether ice streams might increase and sustain rates of mass loss over centuries or millennia, beyond those expected for a given ocean–climate forcing5,6,7,8,9,10. Here we reconstruct the activity of 117 ice streams that operated at various times during deglaciation of the Laurentide Ice Sheet (from about 22,000 to 7,000 years ago) and show that as they activated and deactivated in different locations, their overall number decreased, they occupied a progressively smaller percentage of the ice sheet perimeter and their total discharge decreased. The underlying geology and topography clearly influenced ice stream activity, but—at the ice-sheet scale—their drainage network adjusted and was linked to changes in ice sheet volume. It is unclear whether these findings can be directly translated to modern ice sheets. However, contrary to the view that sees ice streams as unstable entities that can accelerate ice-sheet deglaciation, we conclude that ice streams exerted progressively less influence on ice sheet mass balance during the retreat of the Laurentide Ice Sheet.
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References
Alley, R. B., Clark, P. U., Huybrechts, P. & Joughin, I. Ice-sheet and sea-level changes. Science 310, 456–460 (2005)
Rignot, E. & Kanagaratnam, P. Changes in the velocity structure of the Greenland Ice Sheet. Science 311, 986–990 (2006)
Rignot, H. D. et al. Recent Antarctic ice mass loss from radar interferometry and regional climate modelling. Nature Geosci. 1, 106–110 (2008)
Rignot, E., Velicogna, I., van den Broeke, M. R., Monaghan, A. & Lenaerts, J. T. M. Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise. Geophys. Res. Lett. 38, L05503 (2011)
Golledge, N. R. et al. The multi-millennial Antarctic commitment to future sea-level rise. Nature 526, 421–425 (2015)
Feldmann, J. & Levermann, A. Collapse of the West Antarctic Ice Sheet after local destabilization of the Amundsen Basin. Proc. Natl Acad. Sci. USA 112, 14191–14196 (2015)
Joughin, I., Smith, B. E. & Medley, B. Marine ice sheet collapse potentially under way for the Thwaites Glacier Basin, West Antarctica. Science 344, 735–738 (2014)
Ritz, C. et al. Potential sea-level rise from Antarctic ice-sheet instability constrained by observations. Nature 528, 115–118 (2015)
Intergovernmental Panel on Climate Change (IPCC) in Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (eds Stocker, T. F. et al.) 3–29 (Cambridge Univ. Press, 2013)
Kleman, J. & Applegate, P. J. Durations and propagation patterns of ice sheet instability events. Quat. Sci. Rev. 92, 32–39 (2014)
Rignot, E., Mouginot, J. & Scheuchl, B. Ice flow of the Antarctic ice sheet. Science 333, 1427–1430 (2011)
Rose, K. E. Characteristics of ice flow in Marie Byrd Land, Antarctica. J. Glaciol. 24, 63–75 (1979)
Nghiem, S. V. et al. The extreme melt across the Greenland ice sheet in 2012. Geophys. Res. Lett. 39, L20502 (2012)
Margold, M., Stokes, C. R., Clark, C. D. & Kleman, J. Ice streams in the Laurentide Ice Sheet: a new mapping inventory. J. Maps 11, 380–395 (2015)
Dyke, A. S., Moore, A. & Robertson, L. Deglaciation of North America. Open File Report No. 1574 (Geological Survey of Canada, 2003)
Tarasov, L., Dyke, A. S., Neal, R. M. & Peltier, W. R. A data-calibrated distribution of deglacial chronologies for the North American ice complex from glaciological modeling. Earth Planet. Sci. Lett. 315–316, 30–40 (2012)
Ullman, D. J., Carlson, A. E., Anslow, F. S., LeGrande, A. N. & Licciardi, J. M. Laurentide ice-sheet instability during the last deglaciation. Nature Geosci. 8, 534–537 (2015)
Winsborrow, M. C. M., Clark, C. D. & Stokes, C. R. What controls the location of ice streams? Earth Sci. Rev. 103, 45–59 (2010)
Clark, P. U. Surface form of the southern Laurentide Ice Sheet and its implications to ice-sheet dynamics. Geol. Soc. Am. Bull. 104, 595–605 (1992)
Ó Cofaigh, C., Evans, D. J. A. & Smith, I. R. Large-scale reorganisation and sedimentation of terrestrial ice streams during late Wisconsinan Laurentide Ice Sheet deglaciation. Geol. Soc. Am. Bull. 122, 743–756 (2010)
Stokes, C. R. & Clark, C. D. Laurentide ice streaming over the Canadian Shield: a conflict with the soft-bedded ice stream paradigm? Geology 31, 347–350 (2003)
Carlson, A. E. et al. Surface-melt driven Laurentide Ice Sheet retreat during the early Holocene. Geophys. Res. Lett. 36, L24502 (2009)
Storrar, R. D., Stokes, C. R. & Evans, D. J. A. Increased channelization of subglacial drainage during deglaciation of the Laurentide Ice Sheet. Geology 42, 239–242 (2014)
Mooers, H. D. & Lehr, J. D. Terrestrial record of Laurentide Ice Sheet reorganisation during Heinrich events. Geology 25, 987–990 (1997)
Hemming, S. R. Heinrich events: massive late Pleistocene detritus layers of the North Atlantic and their global climate imprint. Revs. Geophys. 42, RG1005 (2004)
Marcott, S. A. et al. Ice-shelf collapse from subsurface warming as a trigger for Heinrich events. Proc. Natl Acad. Sci. USA 108, 13415–13419 (2011)
Deschamps, P. et al. Ice-sheet collapse and sea-level rise at the Bolling warming 14,600 years ago. Nature 483, 559–564 (2012)
Gregoire, L., Payne, A. J. & Valdes, P. J. Deglacial rapid sea level rises caused by ice-sheet saddle collapses. Nature 487, 219–222 (2012)
Bamber, J. L. et al. A new bed elevation dataset for Greenland. The Cryosphere 7, 499–510 (2013)
Fretwell, P. et al. Bedmap 2: improved ice bed, surface and thickness datasets for Antarctica. The Cryosphere 7, 375–393 (2013)
Patterson, W. S. B. The Physics of Glaciers 3rd edn, 301 (Pergamon, 1994)
Stokes, C. R. & Clark, C. D. Geomorphological criteria for identifying Pleistocene ice streams. Ann. Glaciol. 28, 67–74 (1999)
Dyke, A. S. & Morris, T. F. Drumlin fields, dispersal trains, and ice streams in Arctic Canada. Can. Geogr. 32, 86–90 (1988)
Clark, C. D. Mega-scale glacial lineations and cross-cutting ice flow landforms. Earth Surf. Process. Landf. 18, 1–29 (1993)
King, E. C., Hindmarsh, R. C. A. & Stokes, C. R. Formation of mega-scale glacial lineations observed beneath a West Antarctic ice stream. Nature Geosci. 2, 585–588 (2009)
Clark, C. D. & Stokes, C. R. Extent and basal characteristics of the M’Clintock Channel Ice Stream. Quat. Int. 86, 81–101 (2001)
Hodgson, D. A. Episodic ice streams and ice shelves during retreat of the northwesternmost sector of the late Wisconsinan Laurentide Ice Sheet over the central Canadian Arctic Archipelago. Boreas 23, 14–28 (1994)
Stokes, C. R. & Clark, C. D. Ice stream shear margin moraines. Earth Surf. Process. Landf. 27, 547–558 (2002)
Stokes, C. R. Identification and mapping of palaeo-ice stream geomorphology from satellite imagery: implications for ice stream functioning and ice sheet dynamics. Int. J. Remote Sens. 23, 1557–1563 (2002)
Batchelor, C. L. & Dowdeswell, J. A. The physiography of high Arctic cross-shelf troughs. Quat. Sci. Rev. 92, 68–96 (2014)
Stokes, C. R. & Clark, C. D. Palaeo-ice streams. Quat. Sci. Rev. 20, 1437–1457 (2001)
Ó. Cofaigh, C., Dowdeswell, J. A., Evans, J. & Larter, R. D. Geological constraints on Antarctic palaeo-ice stream retreat. Earth Surf. Process. Landf. 33, 513–525 (2008)
Stokes, C. R., Clark, C. D. & Storrar, R. D. Major changes in ice stream dynamics during deglaciation of the north-western margin of the Laurentide Ice Sheet. Quat. Sci. Rev. 28, 721–738 (2009)
Joughin, I., Smith, B., Howat, I. & Scambos, T. MEaSUREs Greenland Ice Sheet Velocity Map from InSAR Data. https://nsidc.org/data/nsidc-0478 (National Snow and Ice Data Center, 2010)
Joughin, I., Smith, B., Howat, I., Scambos, T. & Moon, T. Greenland flow variability from ice-sheet-wide velocity mapping. J. Glaciol. 56, 415–430 (2010)
Rignot, E., Mouginot, J. & Scheuchl, B. MEaSUREs InSAR-Based Antarctica Ice Velocity Map. http://nsidc.org/data/NSIDC-0484 (National Snow and Ice Data Center, 2011)
Global Digital Evaluation Model (GTOPO30). US Geological Survey, EROS Data Center Distributed Active Archive Center (EDC DAAC) http://eros.usgs.gov/ (2004)
Briner, J. P., Miller, G. H., Davis, P. T. & Finkel, R. C. Cosmogenic radionuclides from fjord landscapes support differential erosion by overriding ice sheets. Geol. Soc. Am. Bull. 118, 406–420 (2006)
Shaw, J. et al. A conceptual model of the deglaciation of Atlantic Canada. Quat. Sci. Rev. 19, 959–980 (2000)
Kleman, J. et al. North American Ice Sheet build-up during the last glacial cycle, 115–21 kyr. Quat. Sci. Rev. 29, 2036–2051 (2010)
Lakeman, T. R. & England, J. H. Palaeo-glaciological insights from the age and morphology of the Jesse moraine belt, western Canadian Arctic. Quat. Sci. Rev. 47, 82–100 (2012)
Lakeman, T. R. & England, J. H. Late Wisconsinan glaciation and postglacial relative sea-level change on western Banks Island, Canadian Arctic Archipelago. Quat. Res. 80, 99–112 (2013)
Jakobsson, M. et al. Arctic Ocean glacial history. Quat. Sci. Rev. 92, 40–67 (2014)
Nixon, F. C. & England, J. H. Expanded Late Wisconsinan ice cap and ice sheet margins in the western Queen Elizabeth Islands, Arctic Canada. Quat. Sci. Rev. 91, 146–164 (2014)
Jakobsson, M. et al. The International Bathymetric Chart of the Arctic Ocean (IBCAO) Version 3.0. Geophys. Res. Lett. 39, L12609 (2012)
ArcticNet. http://www.omg.unb.ca/Projects/Arctic/ [accessed 1 December 2013] (2013)
Margold, M., Stokes, C. R. & Clark, C. D. Ice streams in the Laurentide Ice Sheet: identification, characteristics and comparison to modern ice sheets. Earth Sci. Rev. 143, 117–146 (2015)
Rignot, E., Mouginot, J. & Scheuchl, B. Antarctic grounding line mapping from differential satellite radar interferometry. Geophys. Res. Lett. 38, L10504 (2011)
Acknowledgements
This research was funded by a Natural Environment Research Council award NE/J00782X/1 (C.R.S. and C.D.C.). Landsat imagery and the GTOPO30 digital elevation model were provided free of charge by the US Geological Survey Earth Resources Observation Science Centre.
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C.R.S. designed the study and wrote the proposal with C.D.C. M.M. generated the data on the timing of Laurentide ice streams, modern-ice stream discharge and Laurentide ice stream discharge, and produced the figures, with input from C.R.S. and C.D.C. L.T. contributed data from numerical modelling. All authors contributed to the analyses and interpretations of the data. C.R.S. wrote the manuscript with input from all authors.
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Extended data figures and tables
Extended Data Figure 2 Distribution of dates and interpolated ice margin positions.
These ice margin positions15 (thin red lines) are based on dates (black dots) that we used to bracket the age of the spatial footprint of each Laurentide ice stream (Extended Data Fig. 7). The thick red line shows the updated LGM ice margin (following recent work48,49,50,51,52,53,54). Underlying topography from GTOPO30 digital elevation data47. m a.s.l., metres above sea level.
Extended Data Figure 3 Number of Laurentide ice streams and the percentage of the margin they drained over time, classified according to their underlying geology.
a, A rapid decrease in the number of ice streams is observed after about 12 kyr ago (Fig. 3a), which is linked with the retreat of the LIS onto the hard crystalline rocks of the Canadian Shield19 (cal kyr bp refers to thousands of calendar years before present). b, However, several large, wide ice streams were active over the hard bed geology (see, for example, refs 10, 21), and they drained a large percentage of the perimeter of the ice sheet.
Extended Data Figure 4 Mega-scale glacial lineations34 on the bed of the Dubawnt Lake ice stream21, central Canada.
a–c, These features are a characteristic geomorphological signature of ice streaming and are readily identifiable on Landsat satellite imagery (a, c) and oblique aerial photography (b) of the ice stream bed (number 6 in Extended Data Fig. 1). d, Similar features have been detected beneath Rutford ice stream, West Antarctica35. Landsat imagery courtesy of the US Geological Survey Earth Resources Observation Science Centre; photograph by C.R.S. Images in c and d modified from ref. 35.
Extended Data Figure 5 Landsat imagery of lateral shear margin moraines in the Canadian Arctic Archipelago.
a, b, Beds of the M’Clintock Channel ice stream36,37, Victoria Island (a; number 10 in Extended Data Fig. 1) and the Crooked Lake Ice Stream33, Prince of Wales Island (b; number 11 in Extended Data Fig. 1). Note the abrupt lateral margins (marked by white arrows) of the assemblage of mega-scale glacial lineations that are, in places, marked by lateral shear margin moraines38.
Extended Data Figure 6 Bathymetric data showing cross-shelf troughs and a well-preserved bedform imprint from a submarine setting.
a, Cross-shelf troughs formed by ice streams fed by convergence of ice flow from several fjords along the east coast of Baffin Island. b, c, Drumlins and mega-scale glacial lineations on the floor of Eclipse Sound (b; boxed area in a) and a close-up view of one particular region where subglacial bedforms are well developed (c; boxed area in b). High-resolution swath bathymetry data are from IBCAO55 (a), and from IBCAO55 and ArcticNet56 (b, c). Figure redrawn from ref. 57.
Extended Data Figure 7 Schematic demonstrating the method used to bracket the age of the spatial footprint of Laurentide ice streams in both terrestrial and marine settings.
These methods have been used extensively in previous work, but usually on small samples of ice streams (see, for example, refs 20, 21, 36, 37, 42, 43). a, In some cases, terrestrial ice streams are active, but then deactivate (switch off) as the ice margin retreats, which enables them to be bracketed between a small number of dated ice margins and implies a short duration of operation. b, In other cases, ice streams remain active during deglaciation and continually remould their landform assemblage, leaving a more complicated, time-integrated landform record, often with a series of overprinted landforms, which implies a longer duration of operation. c, d, The same scenarios as in a and b, respectively, but for a topographically controlled marine-terminating ice stream.
Extended Data Figure 8 Location of ice streams in Antarctica where discharge was estimated.
Discharge was estimated from existing data sets of velocity11,46, grounding-line position58 and ice thickness30. Regression analysis reveals a weak relationship between the width and discharge of the ice streams (Extended Data Fig. 10), which we used to estimate the discharge of Laurentide ice streams for which we know only their width (see Methods).
Extended Data Figure 9 Location of ice streams in Greenland where discharge was estimated.
Discharge was estimated from existing data sets of velocity44,45, grounding-line position44,45 and ice thickness29. Regression analysis reveals a weak relationship between the width and discharge of the ice streams (Extended Data Fig. 10), which we used to estimate the discharge of Laurentide ice streams for which we know only their width (see Methods).
Extended Data Figure 10 Relationship between ice stream discharge and width for 81 active ice streams in Antarctica and Greenland.
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Stokes, C., Margold, M., Clark, C. et al. Ice stream activity scaled to ice sheet volume during Laurentide Ice Sheet deglaciation. Nature 530, 322–326 (2016). https://doi.org/10.1038/nature16947
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DOI: https://doi.org/10.1038/nature16947
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