Skip to main content
×
×
Home

Short-term variations in calving of a tidewater glacier: LeConte Glacier, Alaska, U.S.A.

  • Shad O’Neel (a1), Keith A. Echelmeyer (a1) and Roman J. Motyka (a1)
Abstract

Knowledge of iceberg calving is important for understanding instabilities of tidewater glaciers and ice sheets. Since 1995 the terminus of LeConte Glacier, Alaska, U.S.A., has retreated about 2 km and the glacier has thinned approximately 120 m at its 1999 terminus position. Our focus is short-term (hours to weeks) variability of the frequency and magnitude of calving events and calving flux. Both photogrammetric and visual observations are employed in a temporal analysis over a several-week period. We combined these data with measurements of ice speed, tide level, surface water input and water-storage estimates in an attempt to better understand the calving process. Contrary to results obtained over longer time-scales on other glaciers, our results show no correlation between ice speed and the frequency of calving. However, calving events do not appear to occur randomly; often they are a response to measurable changes in other parameters within the terminus region. Caclving can often be attributed to buoyancy perturbations and possibly flexure of the nearly floating terminus. Given the multiple possibilities for buoyancy perturbations, we have found no simple relationship between any specific forcing parameter and calving at short time-scales.

  • 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.

      Short-term variations in calving of a tidewater glacier: LeConte Glacier, Alaska, U.S.A.
      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.

      Short-term variations in calving of a tidewater glacier: LeConte Glacier, Alaska, U.S.A.
      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.

      Short-term variations in calving of a tidewater glacier: LeConte Glacier, Alaska, U.S.A.
      Available formats
      ×
Copyright
References
Hide All
Arendt, A. A., Echelmeyer, K. A., Harrison, W. D., Lingle, C. S. and Valentine, V. B.. 2002. Rapid wastage of Alaska glaciers and their contribution to rising sea level. Science, 297(5580), 382386.
Brown, C. S., Meier, M. F. and Post, A.. 1982. Calving speed of Alaska tidewater glaciers, with application to Columbia Glacier. U.S. Geol. Surv. Prof. Pap. 1258-C.
Clarke, G.K.C. 1987. Fast glacier flow: ice streams, surging and tidewater glaciers. J. Geophys. Res., 92(B9), 88358841.
Echelmeyer, K., Clarke, T. S. and Harrison, W. D.. 1991. Surficial glaciology of Jakobshavns Isbr , West Greenland: Part I. Surface morphology. J. Glaciol., 37(127), 368382.
Fahnestock, M. A. 1991. Hydrologic control of sliding velocity in two Alaskan glaciers: observation and theory. (Ph.D. thesis, California Institute of Technology.)
Godin, G. 1972. The analysis of tides. Toronto, Ont., University of Toronto Press.
Hanson, B. and Hooke, R. LeB.. 2000. Glacier calving: a numerical model of forces in the calving-speed/water-depth relation. J. Glaciol, 46(153), 188196.
Harrison, W. D., Echelmeyer, K. A., Cosgrove, D. M. and Raymond, C. F.. 1992. The determination of glacier speed by time-lapse photography under unfavourable conditions. J. Glaciol., 38(129), 257265.
Hughes, T. 1992. Theoretical calving rates from glaciers along ice walls grounded in water of variable depths. J. Glaciol., 38(129), 282294.
Hunter, L., Motyka, R. J. and Echelmeyer, K. A.. 2001. Sedimentation and denudation rates of a tidewater glacier eroding batholithic bedrock: Le-Conte Glacier, Alaska. [Abstract.] Eos, 82(47), Fall Meeting Supplement, F556.
Hunter, L. E. and Powell, R. D.. 1998. Ice foot development at temperate tidewater margins in Alaska. Geophys. Res. Lett., 25(11), 19231926.
Kamb, B., Engelhardt, H., Fahnestock, M. A., Humphrey, N., Meier, M. and Stone, D.. 1994. Mechanical and hydrologic basis for the rapid motion of a large tidewater glacier. 2. Interpretation. J. Geophys. Res, 99(B8), 15,23115,244.
Krimmel, R. M. 2001. Photogrammetric dataset, 1957–2000, and bathymetric measurements for Columbia Glacier, Alaska. U.S. Geol. Surv. Water-Resour. Invest. Rep. 01-4089.
Krimmel, R. M. and Rasmussen, L. A.. 1986. Using sequential photography to estimate ice velocity at the terminus of Columbia Glacier, Alaska. Ann. Glaciol., 8, 117123.
Krimmel, R. M. and Vaughn, B. H.. 1987. Columbia Glacier, Alaska: changes in velocity 1977–1986. J. Geophys. Res., 92(B9), 89618968.
Mann, D. H. 1986. Reliability of a fjord glacier’s fluctuations for paleoclimatic reconstructions. Quat. Res, 25(1), 1024.
Meier, M. F. 1994. Columbia Glacier during rapid retreat: interactions between glacier flow and iceberg calving dynamics. In Reeh, N., ed. Report of a Workshop on “The Calving Rate of the West Greenland Glaciers in Response to Climate Change”, Copenhagen, 13–15 September 1993. Copenhagen, Danish Polar Center, 6383.
Meier, M. F. and Post, A.. 1987. Fast tidewater glaciers. J. Geophys. Res., 92(B9), 90519058.
Meier, M. and 9 others. 1994. Mechanical and hydrologic basis for the rapid motion of a large tidewater glacier. 1. Observations. J. Geophys. Res., 99(B8), 15,21915,229.
Motyka, R. J. 1997. Deep-water calving at Le Conte Glacier, southeast Alaska. Byrd Polar Res. Cent. Rep. 15, 115118.
Motyka, R. J., Hunter, L., Echelmeyer, K. A. and Connor, C.. 2003. Submarine melting at the terminus of a temperate tidewater glacier, LeConte Glacier, Alaska, U.S.A. Ann. Glaciol., 36, 5765.
O’Neel, S. 2000. Motion and calving at LeConte Glacier, Alaska. (M.Sc. thesis, University of Alaska Fairbanks.)
O’Neel, S., Echelmeyer, K. A. and Motyka, R. J.. 2001. Short-term flow dynamics of a retreating tidewater glacier: LeConte Glacier, Alaska, U.S.A. J. Glaciol., 47(159), 567578.
Pelto, M. S. and Warren, C. R.. 1991. Relationship between tidewater glacier calving velocity and water depth at the calving front. Ann. Glaciol, 15, 115118.
Post, A. 1975. Preliminary hydrography and historic terminal changes of Columbia Glacier, Alaska. U.S. Geol. Surv. Hydrol. Invest. Atlas HA-559, 3 maps. (Scale 1:10,000.)
Post, A. and Motyka, R. J.. 1995. Taku and LeConte Glaciers, Alaska: calving-speed control of Late-Holocene asynchronous advances and retreats. Phys. Geogr., 16(1), 5982.
Qamar, A. 1988. Calving icebergs: a source of low-frequency seismic signals from Columbia Glacier, Alaska. J. Geophys. Res., 93(B6), 66156623.
Reeh, N. 1968. On the calving of ice from floating glaciers and ice shelves. J. Glaciol., 7(50), 215232.
Sikonia, W. G. 1982. Finite-element glacier dynamics model applied to Columbia Glacier, Alaska. U.S. Geol. Surv. Prof. Pap. 1258-B.
Syvitski, J. P. M. 1989. On the deposition of sediment within glacier-influenced fjords: oceanographic controls. Mar. Geol., 85(2/4), 301329.
Van der Veen, C. J. 1996. Tidewater calving. J. Glaciol., 42(141), 375385.
Van der Veen, C. J. 1997. Calving glaciers: report of a Workshop, February 28–March 2, 1997, Columbus, OH. Byrd Polar Res. Cent. Rep. 15.
Van der Veen, C. J. 1998. Fracture mechanics approach to penetration of surface crevasses on glaciers. Cold Reg. Sci.Technol., 27(1), 3147.
Venteris, E. R., Whillans, I. M. and Van der Veen, C. J.. 1997. Effect of extension rate on terminus position, Columbia Glacier, Alaska, U.S.A. Ann. Glaciol., 24, 4953.
Vieli, A., Funk, M. and Blatter, H.. 2000. Tidewater glaciers: frontal flow acceleration and basal sliding. Ann. Glaciol., 31, 217221.
Vieli, A., Funk, M. and Blatter, H.. 2001. Flow dynamics of tidewater glaciers: a numerical modelling approach. J. Glaciol., 47(159), 595606.
Vieli, A., Jania, J. and Kolondra, L.. 2002. The retreat of a tidewater glacier: observations and model calculations on Hansbreen, Spitsbergen. J. Glaciol., 48(163), 592600.
Warren, C. R., Glasser, N. F., Harrison, S., Winchester, V., Kerr, A. R. and Rivera, A.. 1995. Characteristics of tide-water calving at Glaciar San Rafael, Chile. J. Glaciol., 41(138), 273289. (Erratum: 41(139), p. 281.)
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

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