Skip to main content

Thank you for visiting You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

Evolution of the subglacial drainage system beneath the Greenland Ice Sheet revealed by tracers


Predictions of the Greenland Ice Sheet’s response to climate change are limited in part by uncertainty in the coupling between meltwater lubrication of the ice-sheet bed and ice flow1,2,3. This uncertainty arises largely from a lack of direct measurements of water flow characteristics at the bed of the ice sheet. Previous work has been restricted to indirect observations based on seasonal and spatial variations in surface ice velocities4,5,6,7 and on meltwater flux8. Here, we employ rhodamine and sulphur hexafluoride tracers, injected into the drainage system over three melt seasons, to observe subglacial drainage properties and evolution beneath the Greenland Ice Sheet, up to 57 km from the margin. Tracer results indicate evolution from a slow, inefficient drainage system to a fast, efficient channelized drainage system over the course of the melt season. Further inland, evolution to efficient drainage occurs later and more slowly. An efficient routing of water was established up to 41 km or more from the margin, where the ice is approximately 1 km thick. Overall, our findings support previous interpretations of drainage system characteristics, thereby validating the use of surface observations as a means of investigating basal processes.

This is a preview of subscription content

Access options

Buy article

Get time limited or full article access on ReadCube.


All prices are NET prices.

Figure 1: Field site and example traces.
Figure 2: Drainage system characteristics revealed by tracing.


  1. Gillet-Chaulet, F. et al. Greenland Ice Sheet contribution to sea-level rise from a new-generation ice-sheet model. Cryosphere Discuss. 6, 2789–2826 (2012).

    Article  Google Scholar 

  2. Vaughan, D. G. & Athern, R. Why is it so hard to predict the future of ice sheets? Science 315, 1503–1504 (2007).

    Article  Google Scholar 

  3. Solomon, S. et al. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (Cambridge Univ. Press, 2007).

    Google Scholar 

  4. Joughin, I. et al. Seasonal speedup along the western flank of the Greenland Ice Sheet. Science 320, 781–783 (2008).

    Article  Google Scholar 

  5. Bartholomew, I. D. et al. Seasonal evolution of subglacial drainage and acceleration in a Greenland outlet glacier. Nature Geosci. 3, 408–411 (2010).

    Article  Google Scholar 

  6. Bartholomew, I. D. et al. Seasonal variations in Greenland Ice Sheet motion: Inland extent and behaviour at higher elevations. Earth Planet. Sci. Lett. 307, 271–278 (2011).

    Article  Google Scholar 

  7. Palmer, S., Shepherd, A., Nienow, P. & Joughin, I. Seasonal speedup of the Greenland Ice Sheet linked to routing of surface water. Earth Planet. Sci. Lett. 302, 423–428 (2011).

    Article  Google Scholar 

  8. Bartholomew, I. D. et al. Supraglacial forcing of subglacial drainage in the ablation zone of the Greenland ice sheet. Geophys. Res. Lett. 38, L08502 (2011).

    Article  Google Scholar 

  9. Van de Wal, R. S. W. et al. Large and rapid melt-induced velocity changes in the ablation zone of the Greenland Ice Sheet. Science 321, 111–113 (2008).

    Article  Google Scholar 

  10. Shepherd, A. et al. Greenland Ice Sheet motion coupled with daily melting in late summer. Geophys. Res. Lett. 36, L01501 (2009).

    Article  Google Scholar 

  11. Hoffman, M. J., Catania, G. A., Neumann, T. A., Andrews, L. C. & Rumrill, J. A. Links between acceleration, melting, and supraglacial lake drainage of the western Greenland Ice Sheet. J. Geophys. Res. 116, F04035 (2011).

    Article  Google Scholar 

  12. Sundal, A.V. et al. Melt-induced speed-up of Greenland ice sheet offset by efficient subglacial drainage. Nature 469, 521–524 (2011).

    Article  Google Scholar 

  13. Schoof, C. Ice-sheet acceleration driven by melt supply variability. Nature 468, 803–806 (2010).

    Article  Google Scholar 

  14. Iken, A. & Bindschadler, R. A. Combined measurements of subglacial water pressure and surface velocity of Findelengletscher, Switzerland: Conclusions about drainage system and sliding mechanism. J. Glaciol. 32, 101–119 (1986).

    Article  Google Scholar 

  15. Nienow, P. W., Sharp, M. & Willis, I. C. Seasonal changes in the morphology of the subglacial drainage system, Haut Glacier d’Arolla, Switzerland. Earth Surf. Process. 23, 825–843 (1998).

    Article  Google Scholar 

  16. Jansson, P. Dynamics and hydrology of a small polythermal valley glacier. Geogr. Ann. 78A, 171–180 (1996).

    Article  Google Scholar 

  17. Mair, D. et al. Hydrological controls on patterns of surface, internal and basal motion during three spring events: Haut Glacier d’Arolla, Switzerland. J. Glaciol. 49, 555–567 (2003).

    Article  Google Scholar 

  18. Das, S. B. et al. Fracture propagation to the base of the Greenland Ice Sheet during supraglacial lake drainage. Science 320, 778–781 (2008).

    Article  Google Scholar 

  19. Seaberg, S. Z., Seaberg, J. Z., Hooke, R. LeB. & Wieberg, D. Character of the englacial and subglacial drainage system in the lower part of the ablation area of Storglaciären, Sweden, as revealed by dye-trace studies. J. Glaciol. 34, 217–227 (1988).

    Article  Google Scholar 

  20. Hubbard, B. & Nienow, P. Alpine subglacial hydrology. Quat. Sci. Rev. 16, 939–955 (1997).

    Article  Google Scholar 

  21. Bingham, R. G., Nienow, P. W., Sharp, M. J. & Boon, S. Subglacial drainage processes at a High Arctic polythermal valley glacier. J. Glaciol. 51, 15–24 (2005).

    Article  Google Scholar 

  22. Smart, P. L. & Laidlaw, I. M. S. An evaluation of some fluorescent dyes for water tracing. Wat. Resour. Res. 31, 15–33 (1977).

    Article  Google Scholar 

  23. Watson, A. J., Liddicoat, M. I. & Ledwell, J. R. Perfluorodecalin and sulphur hexafluoride as purposeful marine tracers: Some deployment and analysis techniques. Deep-Sea Res. 34, 19–31 (1987).

    Article  Google Scholar 

  24. Clark, J. F., Schlosser, P., Stute, M. & Simpson, H. J. SF6−3He tracer release experiment: A new method of determining longitudinal dispersion coefficients in large rivers. Environ. Sci. Technol. 30, 1527–1532 (1996).

    Article  Google Scholar 

  25. Dillon, K. S., Corbett, D. R., Chanton, J. P., Burnett, W. C. & Kump, L. Bimodal transport of a waste water plume injected into saline ground water of the Florida Keys. Ground Wat. 38, 624–634 (2000).

    Article  Google Scholar 

  26. Rigby, M. et al. History of atmospheric SF6 from 1973–2008. Atmos. Chem. Phys. 0, 10305–10320 (2010).

    Article  Google Scholar 

  27. Upstill-Goddard, R. C. & Wilkins, C. S. The potential of SF6 as a geothermal tracer. Wat. Resour. Res. 29, 1065–1068 (1995).

    Article  Google Scholar 

  28. Smeets, C. J. P. P. et al. A wireless subglacial probe for deep ice applications. J. Glaciol. 58, 841–848 (2012).

    Article  Google Scholar 

  29. Allen, C. IceBridge MCoRDS L2 Ice Thickness [2010, 2011]. Boulder, Colorado, USA: NASA DAAC at the National Snow and Ice Data Center. Digital media. (2010, updated current year).

  30. Nienow, P., Sharp, M & Willis, I. Velocity–discharge relationships derived from dye tracer experiments in glacial meltwaters: Implications for subglacial flow conditions. Hydrol. Process. 10, 1411–1426 (1996).

    Article  Google Scholar 

Download references


This work was supported by the Leverhulme Trust (Phillip Leverhulme Prize to J.L.W.), UK NERC grant NE/H023879/1 to J.L.W., NERC NE/F021380/1 grant to P.N., NERC grant NE/G005796/1 to A.H, financial support from the Greenland Analogue Project and SKB/Positiva to A.H., and Moss Scholarships to T.C. and I.B. We thank the Atmospheric Chemistry Research Group at the University of Bristol who aided with SF6 analysis in the early stages of the project. We acknowledge the use of ice thickness data collected by the NASA IceBridge project. We thank Hozelock for supplying hoses, and are grateful to the many field assistants who have contributed to the collection of field data.

Author information

Authors and Affiliations



D.M.C. designed the tracer experiments in the field and conducted tracer data analysis, developed the model of drainage evolution and co-wrote the manuscript. J.L.W. led the project, designed the tracer experiments in the field and conducted tracer data analysis, and co-wrote the manuscript with D.M.C. G.P.L., S.V. and J.T. were responsible for SF6 analysis by gas chromatography and method development. P.N., D.M.C., A.S., T.C. and I.B. contributed discharge and dye tracing data, and input to writing of the manuscript. E.B.B. contributed to field logistics and input to writing of the manuscript. A.H. was responsible for in-field support of the campaign, provided ice thickness data and input to writing of manuscript.

Corresponding author

Correspondence to J. L. Wadham.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Information (PDF 4887 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Chandler, D., Wadham, J., Lis, G. et al. Evolution of the subglacial drainage system beneath the Greenland Ice Sheet revealed by tracers. Nature Geosci 6, 195–198 (2013).

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI:

Further reading


Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing