Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-25T16:18:31.186Z Has data issue: false hasContentIssue false

Mapping the grounding zone of the Amery Ice Shelf, East Antarctica using InSAR, MODIS and ICESat

Published online by Cambridge University Press:  01 October 2009

Helen Amanda Fricker*
Affiliation:
Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Dr, La Jolla, CA 92093-0225, USA
Richard Coleman
Affiliation:
Centre for Marine Science, University of Tasmania, Private Bag 115, Hobart, TAS 7001, Australia Antarctic Climate and Ecosystems CRC, Hobart, Australia CSIRO Marine and Atmospheric Research, Hobart, Australia
Laurie Padman
Affiliation:
Earth & Space Research, 3350 SW Cascade Ave, Corvallis, OR 97333-1536, USA
Ted A. Scambos
Affiliation:
National Snow and Ice Data Center, CIRES, Campus Box 449, 1540 30th St, University of Colorado, Boulder, CO 80309-0449, USA
Jennifer Bohlander
Affiliation:
National Snow and Ice Data Center, CIRES, Campus Box 449, 1540 30th St, University of Colorado, Boulder, CO 80309-0449, USA
Kelly M. Brunt
Affiliation:
Institute of Geophysics and Planetary Physics, Scripps Institution of Oceanography, University of California, San Diego, 9500 Gilman Dr, La Jolla, CA 92093-0225, USA

Abstract

We use a combination of satellite techniques (interferometric synthetic aperture radar (InSAR), visible-band imagery, and repeat-track laser altimetry) to develop a benchmark map for the Amery Ice Shelf (AIS) grounding zone (GZ), including its islands and ice rises. The break-in-slope, as an indirect estimate of grounding line location, was mapped for the entire AIS. We have also mapped ∼55% of the landward edge and ∼30% of the seaward edge of the ice shelf flexure boundary for the AIS perimeter. Vertical ice motion from Global Positioning System receivers confirms the location of the satellite-derived GZ in two regions. Our map redefines the extent of floating ice in the south-western AIS and identifies several previously unmapped grounded regions, improving our understanding of the stresses supporting the current dynamical state of the ice shelf. Finally, we identify three along-flow channels in the ice shelf basal topography, approximately 10 km apart, 1.5 km wide and 300–500 m deep, near the southern GZ. These channels, which form at the suture zones between ice streams, may represent zones of potential weakness in the ice shelf and may influence sub-ice-shelf ocean circulation.

Type
Physical Sciences
Copyright
Copyright © Antarctic Science Ltd 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Budd, W.F., Corry, M.J.Jacka, T.H. 1982. Results from the Amery Ice Shelf project. Annals of Glaciology, 3, 3641.CrossRefGoogle Scholar
Chelton, D.B.Enfield, D.B. 1986. Ocean signals in tide gauge records. Journal of Geophysical Research, 91, 90819098.CrossRefGoogle Scholar
Chen, G. 1998. GPS Kinematic positioning for the Airborne Laser Altimetry at Long Valley, California. PhD thesis, Massachusetts Institute of Technology, Cambridge, 173 pp.Google Scholar
Corr, H.F.J., Doake, C.S.M., Jenkins, A.Vaughan, D.G. 2001. Investigations of an “ice plain” in the mouth of Pine Island Glacier, Antarctica. Journal of Glaciology, 47, 5157.CrossRefGoogle Scholar
Craven, M., Allison, I., Fricker, H.A.Warner, R. In press. Properties of the marine ice layer under the Amery Ice Shelf. Journal of Glaciology.Google Scholar
Craven, M., Carsey, F., Behar, A., Matthews, J., Brand, R., Elcheikh, A., Hall, S.Treverrow, A. 2005. Borehole imagery of meteoric and marine ice layers in the Amery Ice Shelf. Journal of Glaciology, 51, 7584.CrossRefGoogle Scholar
Fricker, H.A.Padman, L. 2006. Ice shelf grounding zone structure from ICESat laser altimetry. Geophysical Research Letters, 33, 10.1029/2006GL026907.CrossRefGoogle Scholar
Fricker, H.A., Hyland, G., Coleman, R.Young, N.W. 2000. Digital elevation models for the Lambert Glacier–Amery Ice Shelf system, East Antarctica, from ERS-1 satellite radar altimetry. Journal of Glaciology, 46, 553560.CrossRefGoogle Scholar
Fricker, H.A., Popov, S., Allison, I.Young, N.W. 2001. Distribution of marine ice beneath the Amery Ice Shelf. Geophysical Research Letters, 28, 22412244.CrossRefGoogle Scholar
Fricker, H.A., Young, N.W., Allison, I.Coleman, R. 2002b. Iceberg calving from the Amery Ice Shelf, East Antarctica. Annals of Glaciology, 34, 241246.CrossRefGoogle Scholar
Fricker, H.A., Allison, I., Craven, M., Hyland, G., Ruddell, A., Young, N., Coleman, R., King, M., Krebs, K.Popov, S. 2002a. Redefinition of the grounding zone of Amery Ice Shelf, East Antarctica. Journal of Geophysical Research, 107, 10.1029/2001JB000383.CrossRefGoogle Scholar
Galton-Fenzi, B., Maraldi, C., Coleman, R.Hunter, J. 2008. The cavity under the Amery Ice Shelf, East Antarctica. Journal of Glaciology, 54, 881887.CrossRefGoogle Scholar
Goldstein, R.M., Engelhardt, H., Kamb, B.Frolich, R.M. 1993. Satellite radar interferometry for monitoring ice sheet motion: application to an Antarctic ice stream. Science, 262, 15251530.CrossRefGoogle Scholar
Gray, L., Short, N., Bindschadler, R., Joughin, I., Padman, L., Vornberger, P.Khananian, A. 2002. RADARSAT interferometry for Antarctic grounding zone mapping. Annals of Glaciology, 34, 269276.CrossRefGoogle Scholar
Haran, T.M., Fahnestock, M.A.Scambos, T.A. 2002. De-striping of MODIS optical bands for ice sheet mapping and topography. Eos Transaction of the American Geophysical Union, 88, F317.Google Scholar
Hemer, M.A., Hunter, J.H.Coleman, R. 2006. Barotropic tides beneath the Amery Ice Shelf. Journal of Geophysical Research, 111, 10.1029/2006JGRC.11111008H.CrossRefGoogle Scholar
Holdsworth, G. 1969. Flexure of a floating ice tongue. Journal of Glaciology, 8, 385397.CrossRefGoogle Scholar
Horgan, H.J.Anandakrishnan, S. 2006. Static grounding lines and dynamic ice streams: evidence from the Siple Coast, West Antarctica. Geophysical Research Letters, 33, 10.1029/2006GL027091.CrossRefGoogle Scholar
Joughin, I. 2002. Ice-sheet velocity mapping: a combined interferometric and speckle-tracking approach. Annals of Glaciology, 34, 195201.CrossRefGoogle Scholar
King, M.Aoki, S. 2003. Tidal observations on floating ice using a single GPS receiver. Geophysical Research Letters, 30, 10.1029/2002GL016182.CrossRefGoogle Scholar
King, R.W.Bock, Y. 2006. Documentation for the GAMIT GPS analysis software, version 10.3. Cambridge, MA: Massachusetts Institute of Technology.Google Scholar
King, M.A., Coleman, R., Morgan, P.J.Hurd, R.S. 2007. Velocity change of the Amery Ice Shelf, East Antarctica, during the period 1968–1999. Journal of Geophysical Research, 112, 10.1029/2006JF000609.CrossRefGoogle Scholar
King, M.A., Nguyen, N.L., Coleman, R.Morgan, P.J. 2000. GPS measurements on the Amery Ice Shelf, East Antarctica. GPS Solutions, 4, 212.CrossRefGoogle Scholar
King, M.A., Coleman, R., Freemantle, A., Fricker, H.A., Hurd, R.S., Legrésy, B., Padman, L.Warner, R. 2009. A four-decade record of elevation change of the Amery Ice Shelf, East Antarctica. Journal of Geophysical Research, 114, 10.1029/2008JF001094.CrossRefGoogle Scholar
Lacroix, P., Legresy, B., Coleman, R., Dechambre, M.Remy, F. 2007. Dual-frequency altimeter signal from Envisat on the Amery Ice Shelf. Remote Sensing of Environment, 109, 285294.CrossRefGoogle Scholar
Lemke, P., Ren, J., Alley, R.B., Allison, I., Carrasco, J., Flato, G., Fujii, Y., Kaser, G., Mote, P., Thomas, R.H.Zhang, T. 2007. Observations: changes in snow, ice and frozen ground. In Solomon, S., Qin, D., Manning, M., Chen, Z., Marquis, M., Averyt, K.B., Tignor, M. & Miller, H.L., eds. Climate change 2007: the physical science basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge: Cambridge University Press, 339383.Google Scholar
Padman, L., Fricker, H.A., Coleman, R., Howard, S.L.Erofeeva, S. 2002. A new tide model for the Antarctic ice shelves and seas. Annals of Glaciology, 34, 247254.CrossRefGoogle Scholar
Padman, L., King, M., Goring, D., Corr, H.Coleman, R. 2003. Ice shelf elevation changes due to atmospheric pressure variations. Journal of Glaciology, 49, 521526.CrossRefGoogle Scholar
Phillips, H.A. 1998. Surface meltstreams on the Amery Ice Shelf, East Antarctica. Annals of Glaciology, 27, 177181.CrossRefGoogle Scholar
Rabus, B.Lang, O. 2002. On the representation of ice-shelf grounding zones in SAR interferograms. Journal of Glaciology, 46, 345356.CrossRefGoogle Scholar
Riedel, B., Nixdorf, U., Heinert, M., Eckstaller, A.Mayer, C. 1999. The response of the Ekströmisen (Antarctica) grounding zone to tidal forcing. Annals of Glaciology, 29, 239242.CrossRefGoogle Scholar
Rignot, E. 1998a. Fast recession of a West Antarctic glacier. Science, 281, 549551.CrossRefGoogle Scholar
Rignot, E. 1998b. Hinge-line migration of Petermann Gletscher, north Greenland, detected using satellite-radar Interferometry. Journal of Glaciology, 44, 469476.CrossRefGoogle Scholar
Rignot, E. 2002. Mass balance of East Antarctic glaciers and ice shelves from satellite data. Annals of Glaciology, 34, 217227.CrossRefGoogle Scholar
Rignot, E.MacAyeal, D.R. 1998. Ice-shelf dynamics near the front of the Filchner–Ronne Ice Shelf, Antarctica, revealed by SAR interferometry. Journal of Glaciology, 44, 405418.CrossRefGoogle Scholar
Rignot, E.Steffen, K. 2008. Channelized bottom melting and stability of floating ice shelves. Geophysical Research Letters, 35, 10:1029/21007GL031765.CrossRefGoogle Scholar
Rignot, E., Padman, L., MacAyeal, D.R.Schmeltz, M. 2000. Observation of ocean tides below the Filchner and Ronne Ice Shelves, Antarctica, using synthetic aperture radar: comparison with tide model predictions. Journal of Geophysical Research, 105, 1961519630.CrossRefGoogle Scholar
Sandwell, D.T.Price, E.J. 1998. Phase gradient approach to stacking interferograms. Journal of Geophysical Research, 103, 3018330204.CrossRefGoogle Scholar
Scambos, T.A., Hulbe, C.Fahnestock, M.A. 2003. Climate-induced ice shelf disintegration in the Antarctic Peninsula. Antarctic Research Series, 79, 7992.Google Scholar
Scambos, T., Kvaran, G.Fahnestock, M. 1999. Improving AVHRR resolution through data cumulation for mapping polar ice sheets. Remote Sensing of the Environment, 69, 5666.CrossRefGoogle Scholar
Scambos, T., Hulbe, C., Fahnestock, M.Bohlander, J. 2000. The link between climate warming and break-up of ice shelves in the Antarctic Peninsula. Journal of Glaciology, 46, 516530.CrossRefGoogle Scholar
Scambos, T.A., Haran, T.M., Fahnestock, M.A., Painter, T.H.Bohlander, J. 2007. MODIS-based mosaic of Antarctica (MOA) data sets: continent-wide surface morphology and snow grain size. Remote Sensing of the Environment, 111, 10.1016/j.rse.2006.12.020.CrossRefGoogle Scholar
Schmeltz, M., Rignot, E.MacAyeal, D.R. 2001. Ephemeral grounding as a signal of ice shelf change. Journal of Glaciology, 47, 7177.CrossRefGoogle Scholar
Shepherd, A., Wingham, D., Payne, T.Skvarca, P. 2003. Larsen Ice Shelf has progressively thinned. Science, 302, 856859.CrossRefGoogle ScholarPubMed
Shuman, C.A., Zwally, H.J., Schutz, B.E., Brenner, A.C., DiMarzio, J.P., Suchdeo, V.P.Fricker, H.A. 2006. ICESat Antarctic elevation data: preliminary precision and accuracy assessment. Geophysical Research Letters, 33, 10.1029/2005GL025227.CrossRefGoogle Scholar
Stephenson, S.N., Doake, C.S.M.Horsfall, J.A.C. 1979. Tidal flexure of ice shelves measured by tiltmeter. Nature, 282, 496497.CrossRefGoogle Scholar
Turcotte, D.L.Schubert, G. 2001. Geodynamics. Cambridge: Cambridge University Press, 528 pp.Google Scholar
Vaughan, D.G. 1994. Investigating tidal flexure on an ice shelf using kinematic GPS. Annals of Glaciology, 20, 372376.CrossRefGoogle Scholar
Vaughan, D.G. 1995. Tidal flexure at ice shelf margins. Journal of Geophysical Research, 100, 62136224.CrossRefGoogle Scholar
Young, N.W.Hyland, G. 2002. Velocity and strain rates derived from InSAR analysis over the Amery Ice Shelf. Annals of Glaciology, 34, 228234.CrossRefGoogle Scholar
Zhang, X.Andersen, O.B. 2006. Surface ice flow velocity and tide retrieval of the Amery Ice Shelf using precise point positioning. Journal of Geodesy, 80, 171176.CrossRefGoogle Scholar