Acceleration of Jakobshavn Isbræ triggered by warm subsurface ocean waters

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Abstract

Observations over the past decades show a rapid acceleration of several outlet glaciers in Greenland and Antarctica1. One of the largest changes is a sudden switch of Jakobshavn Isbræ, a large outlet glacier feeding a deep-ocean fjord on Greenland’s west coast, from slow thickening to rapid thinning2 in 1997, associated with a doubling in glacier velocity3. Suggested explanations for the speed-up of Jakobshavn Isbræ include increased lubrication of the ice–bedrock interface as more meltwater has drained to the glacier bed during recent warmer summers4 and weakening and break-up of the floating ice tongue that buttressed the glacier5. Here we present hydrographic data that show a sudden increase in subsurface ocean temperature in 1997 along the entire west coast of Greenland, suggesting that the changes in Jakobshavn Isbræ were instead triggered by the arrival of relatively warm water originating from the Irminger Sea near Iceland. We trace these oceanic changes back to changes in the atmospheric circulation in the North Atlantic region. We conclude that the prediction of future rapid dynamic responses of other outlet glaciers to climate change will require an improved understanding of the effect of changes in regional ocean and atmosphere circulation on the delivery of warm subsurface waters to the periphery of the ice sheets.

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Figure 1: Larger-scale setting and regional-scale bathymetry.
Figure 2: Elevation and velocity changes in Jakobshavn Isbræ.
Figure 3: Oceanographic and meteorological observations near Jakobshavn.
Figure 4: Subsurface ocean temperatures over the west Greenland continental shelf.

References

  1. 1

    Rignot, E. & Kanagaratnam, P. Changes in the velocity structure of the Greenland Ice Sheet. Science 311, 986–990 (2006).

  2. 2

    Thomas, R. H. et al. Investigation of surface melting and dynamic thinning on Jakobshavn Isbræ. J. Glaciol. 49, 231–239 (2003).

  3. 3

    Joughin, I., Abdalati, W. & Fahnestock, M. Large fluctuations in speed on Greenland’s Jakobshavn Isbræ glacier. Nature 432, 608–610 (2004).

  4. 4

    Zwally, H. J. et al. Surface melt-induced acceleration of Greenland Ice-Sheet flow. Science 297, 218–222 (2002).

  5. 5

    Thomas, R. H. Force-perturbation analysis of recent thinning and acceleration of Jakobshavn Isbræ Greenland. J. Glaciol. 50, 57–66 (2004).

  6. 6

    Csatho, B., Schenk, T., van der Veen, C. J. & Krabill, W. B. Intermittent thinning of Jakobshavn Isbræ, West Greenland, since the Little Ice Age. J. Glaciol. 54, 131–144 (2008).

  7. 7

    Buch, E., Pedersen, S. A. & Ribergaard, M. H. Ecosystem variability in West Greenland waters. J. Northw. Atl. Fish. Sci. 34, 13–28 (2004).

  8. 8

    Krabill, W. et al. Greenland Ice Sheet: High-elevation balance and peripheral thinning. Science 289, 428–430 (2000).

  9. 9

    Thomas, R. H., Krabill, W., Frederick, E. & Jezek, K. Thickening of Jakobshavn Isbræ, West Greenland, measured by airborne laser altimetry. Ann. Glaciol. 21, 259–262 (1995).

  10. 10

    MacAyeal, D. R. Thermohaline circulation below the Ross Ice Shelf: A consequence of tidally-induced vertical mixing and basal melting. J. Geophys. Res. 89, 597–606 (1984).

  11. 11

    Holland, P. R., Jenkins, A. & Holland, D. M. The nonlinear response of ice-shelf basal melting to variation in ocean temperature. J. Clim. 15, 2558–2572 (2008).

  12. 12

    Ribergaard, M. H. Oceanographic investigations off West Greenland 2006. NAFO Sci. Council Documents 07/001 (2007).

  13. 13

    Myers, P. G., Kulan, N. & Ribergaard, M. H. Irminger water variability in the West Greenland Current. Geophys. Res. Lett. 34, doi:L17601/10.1029/2007GL030419 (2007).

  14. 14

    Scharling, M., Rajakumar, K., Hansen, L. & Jensen, J. J. Catalogue of meteorological observing stations operated by DMI. Technical Report 06–11, <www.dmi.dk/dmi/tr06-11> (2006).

  15. 15

    Wieland, K. & Kanneworff, P. Bottom temperature on West Greenland shrimp fishing grounds in 1991 to 2002. NAFO SCR Document 02/162 (2002).

  16. 16

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

  17. 17

    Joughin, I. Greenland rumbles louder as glaciers accelerate. Science 311, 1719–1720 (2006).

  18. 18

    Thomas, R. H., Frederick, E., Krabill, W., Manizade, S. & Martin, C. Recent changes in Greenland outlet glaciers. J. Glaciol. (2008, in the press).

  19. 19

    Stein, M. North Atlantic subpolar gyre warming—impacts on Greenland offshore waters. J. Northw. Atl. Fish. Sci. 36, 43–54 (2005).

  20. 20

    Holliday, N. P. et al. Reversal of the 1960s to 1990s freshening trend in the northeast North Atlantic and Nordic Seas. Geophys. Res. Lett. 35, L03614 (2008).

  21. 21

    Mortensen, J. & Valdimarsson, H. Thermohaline changes in the Irminger Sea. ICES CM 1999/L:16 (1999).

  22. 22

    Flatau, M. K., Talley, L. & Niiler, P. P. The North Atlantic Oscillation, surface current velocities, and SST changes in the subpolar North Atlantic. J. Clim. 16, 2355–2369 (2003).

  23. 23

    Hakkinen, S. & Rhines, P. B. Decline of subpolar North Atlantic circulation during the 1990s. Science 304, 555–559 (2004).

  24. 24

    Hátún, H., Sandø, A. B., Drange, H., Hansen, B. & Valdimarsson, H. Influence of the Atlantic subpolar gyre on the thermohaline circulation. Science 309, 1841–1844 (2005).

  25. 25

    Intergovernmental Panel on Climate Change, IPCC Fourth Assessment Report—Climate Change 2007: The Physical Science Basis Summary for Policymakers. <http://www.ipcc.ch/ipccreports/ar4-wg1.htm>(2007).

  26. 26

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

  27. 27

    Clarke, T. & Echelmeyer, K. Seismic-reflection evidence for a deep subglacial trough beneath Jakobshavns Isbræ, West Greenland. J. Glaciol. 42, 219–232 (1996).

  28. 28

    Plummer, J., Gogineni, S., van der Veen, C., Leuschen, C. & Li, J. Ice thickness and bed map for Jakobshavn Isbræ. CReSIS Tech. Report, 2008-1, (2008).

  29. 29

    Hammer, R. R. J. Undersogelser ved Jakobshavns Isfjord og naermeste omegen i vinteren 1879-80. Meddr. Gronland 4, 3–67 (1883).

  30. 30

    Drinkwater, K. F. The regime shift of the 1920s and 1930s in the North Atlantic. Prog. Oceanogr. 68, 134–151 (2006).

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Acknowledgements

This research was primarily supported by a Strategic Grant for Exploratory Research from the Office of Polar Programs of the National Science Foundation (ARC-0644156).

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Correspondence to David M. Holland.

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Holland, D., Thomas, R., de Young, B. et al. Acceleration of Jakobshavn Isbræ triggered by warm subsurface ocean waters. Nature Geosci 1, 659–664 (2008) doi:10.1038/ngeo316

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