Skip to main content
×
×
Home

Investigation of surface melting and dynamic thinning on Jakobshavn Isbræ, Greenland

  • Robert H. Thomas (a1), Waleed Abdalati (a2), Earl Frederick (a1), William B. Krabill (a3), Serdar Manizade (a1) and Konrad Steffen (a4)...
Abstract

Jakobshavn Isbræ is the most active glacier in Greenland, with an annual discharge of about 30 km3 of ice, and it is one of the few recently surveyed glaciers to thicken between 1993 and 1998, despite locally warm summers. Repeated airborne laser-altimeter surveys along a 120 km profile in the glacier basin show slow, sporadic thickening between 1991 and 1997, suggesting a small positive mass balance, but since 1997 there has been sustained thinning of several m a−1 within 20 km of the ice front, with lower rates of thinning further inland. Here, we use weather-station data from the coast and the ice sheet to estimate the effects on surface elevation of interannual variability in snowfall and surface melt rates, and thus to infer the temporal and spatial patterns of dynamic thinning. These show the glacier to have been close to balance before 1997 followed by a sudden transition to rapid thinning, initially confined to the lower reaches of the glacier (below about 500 m elevation), but progressively spreading inland until, between 1999 and 2001, thinning predominated over the entire surveyed region, up to 2000 m elevation. If this continues, the glacier calving front and probably its grounding line will retreat substantially in the very near future.

  • View HTML
    • Send article to Kindle

      To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle. Find out more about sending to your Kindle.

      Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

      Find out more about the Kindle Personal Document Service.

      Investigation of surface melting and dynamic thinning on Jakobshavn Isbræ, Greenland
      Available formats
      ×
      Send article to Dropbox

      To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Dropbox.

      Investigation of surface melting and dynamic thinning on Jakobshavn Isbræ, Greenland
      Available formats
      ×
      Send article to Google Drive

      To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your <service> account. Find out more about sending content to Google Drive.

      Investigation of surface melting and dynamic thinning on Jakobshavn Isbræ, Greenland
      Available formats
      ×
Copyright
References
Hide All
Abdalati, W. and Krabill, W. B.. 1999. Calculation of ice velocities in the Jakobshavn Isbræ area using airborne laser altimetry. Remote Sensing Environ., 67(2), 194204.
Abdalati, W. and Steffen, K.. 2001. Greenland ice sheet melt extent: 1979–1999. J. Geophys. Res., 106(D24), 33,98333,988.
Abdalati, W. and 9 others. 2001. Outlet glacier and margin elevation changes: near-coastal thinning of the Greenland ice sheet. J. Geophys. Res., 106(D24), 33,72933,742.
Braithwaite, R. J. 1981. On glacier energy balance, ablation, and air temperature. J. Glaciol., 27(97), 381391.
Braithwaite, R.J. 1995. Positive degree-day factors for ablation on the Greenland ice sheet studied by energy-balance modelling. J. Glaciol., 41(137), 153160.
Carbonnell, M. and Bauer, A.. 1968. Exploitation des couvertures photographiques aériennes répétées du front des glaciers vêlant dans Disko Bugt et Umanak Fjord, juin–juillet, 1964. Medd. Grønl., 173(5).
Dickson, R. R. and 8 others. 2000. The Arctic Ocean response to the North Atlantic Oscillation. J. Climate, 13(15), 26712696.
Echelmeyer, K. and Harrison, W. D.. 1990. Jakobshavns Isbræ, West Greenland: seasonal variations in velocity — or lack thereof. J. Glaciol., 36(122), 8288.
Echelmeyer, K., Clarke, T. S. and Harrison, W. D.. 1991. Surficial glaciology of Jakobshavns Isbræ, West Greenland: Part I. Surface morphology. J. Glaciol., 37(127), 368382.
Echelmeyer, K., Harrison, W. D., Clarke, T. S. and Benson, C.. 1992. Surficial glaciology of Jakobshavns Isbræ, West Greenland: Part II. Ablation, accumulation and temperature. J. Glaciol., 38(128), 169181.
Fastook, J. L., Brecher, H. H. and Hughes, T. J.. 1995. Derived bedrock elevations, strain rates and stresses from measured surface elevations and velocities: Jakobshavns Isbræ, Greenland. J. Glaciol., 41(137), 161173.
Häkkinen, S. 1999.Variability of the simulated meridional heat transport in the North Atlantic for the period 1951–1993. J. Geophys. Res., 104(C5), 10,99111,007.
Häkkinen, S. 2001. Variability in sea surface height: a qualitative measure for the meridional overturning in the North Atlantic. J. Geophys. Res., 106(C7), 13,83713,848.
Hughes, T. 1986.The Jakobshavns effect. Geophys. Res. Lett., 13(1), 4648.
Hughes, T. J. 1998. Ice sheets. NewYork, etc., Oxford University Press.
Iken, A., Echelmeyer, K., Harrison, W. and Funk, M.. 1993. Mechanisms of fast flow inJakobshavns Isbræ,West Greenland: Part I. Measurements of temperature and water level in deep boreholes. J. Glaciol., 39(131), 1525.
Jacobs, S. S., Hellmer, H. H., Doake, C. S. M., Jenkins, A. and Frolich, R. M.. 1992. Melting of ice shelves and the mass balance of Antarctica. J. Glaciol., 38(130), 375387.
Jenkins, A., Vaughan, D. G., Jacobs, S. S., Hellmer, H. H. and Keys, J. R.. 1997. Glaciological and oceanographic evidence of high melt rates beneath Pine Island Glacier, West Antarctica. J. Glaciol., 43(143), 114121.
Krabill, W. B., Thomas, R. H., Martin, C. F., Swift, R. N. and Frederick, E. B.. 1995. Accuracy of airborne laser altimetry over the Greenland ice sheet. Int. J. Remote Sensing, 16(7), 12111222.
Krabill, W. and 8 others. 1999. Rapid thinning of parts of the southern Greenland ice sheet. Science, 283(5407), 15221524.
Krabill, W. B. and 9 others. 2000. Greenland ice sheet: high-elevation balance and peripheral thinning. Science, 289(5478), 428430.
Krabill, W. B. and 8 others. 2002. Aircraft laser altimetry measurements of changes of the Greenland ice sheet: technique and accuracy assessment. J. Geodyn., 34, 357376.
Lingle, C. S., Hughes, T. J. and Kollmeyer, R. C.. 1981. Tidal flexure of Jakobshavns glacier, West Greenland. J. Geophys. Res., 86(B5), 39603968.
Morison, J., Aagaard, K. and Steele, M.. 2000. Recent environmental changes in the Arctic: a review. Arctic, 53(4), 359371.
Paterson, W. S. B. 1994.The physics of glaciers. Third edition. Oxford, etc., Elsevier.
Reeh, N. 1991. Parameterization of melt rate and surface temperature on the Greenland ice sheet. Polarforschung, 59(3), 1989, 113128.
Rignot, E. 1996. Tidal motion, ice velocity and melt rate of Petermann Gletscher, Greenland, measured from radar interferometry. J. Glaciol., 42(142), 476485.
Rignot, E. and Jacobs, S. S.. 2002. Rapid bottom melting widespread near Antarctic ice sheet grounding lines. Science, 296(5575), 20202023.
Serreze, M. C. and 9 others. 2000. Observational evidence of recent change in the northern high-latitude environment. Climatic Change, 46(2), 159207.
Sohn, H.-G., Jezek, K. C. and van der Veen, C. J.. 1998. Jakobshavn Glacier, West Greenland: thirty years of spaceborne observations. Geophys. Res. Lett., 25(14), 26992702.
Steele, M. and Boyd, T.. 1998. Retreat of the cold halocline layer in the Arctic Ocean. J. Geophys. Res., 103(C5), 10,41910,435.
Steffen, K. and Box, J.. 2001. Surface climatology of the Greenland ice sheet: Greenland Climate Network 1995–1999. J. Geophys. Res., 106(D24), 33,95133,964.
Thomas, R. H. 1973.The creep of ice shelves: theory. J. Glaciol., 12(64), 4553.
Van der Veen, C.J. 1999. Fundamentals of glacier dynamics. Rotterdam, etc., A. A. Balkema Publishers.
Weidick, A. 1995. Greenland, with a section on Landsat images of Greenland by Richard S. Williams, Jr. and Jane G. Ferrigno. U.S. Geol. Surv. Prof. Pap. 1386-C.
Zwally, H. J., Abdalati, W., Herring, T., Larson, K., Saba, J. and Steffen, K.. 2002. Surface melt-induced acceleration of Greenland ice-sheet flow. Science, 297(5579), 218222.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Journal of Glaciology
  • ISSN: 0022-1430
  • EISSN: 1727-5652
  • URL: /core/journals/journal-of-glaciology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *
×

Metrics

Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed