HR: 14:15h
AN: NS43A-04 [Abstracts]
TI: Grounding line position of Whillans Ice Stream, West Antarctica .
AU: * Anandakrishnan, S
EM: sak@essc.psu.edu
AF: Department of Geosciences and Earth and Environmental Systems Institute, The Pennsylvania State
University, University Park, PA 16802 United States
AU: Horgan, H
EM: hhorgan@geosc.psu.edu
AF: Department of Geosciences and Earth and Environmental Systems Institute, The Pennsylvania State
University, University Park, PA 16802 United States
AU: Catania, G
EM: ginny@ess.washington.edu
AF: Department of Earth and Space Sciences, University of Washington, Seattle, WA 98195 United States
AU: Voigt, D
EM: voigt@geosc.psu.edu
AF: Department of Geosciences and Earth and Environmental Systems Institute, The Pennsylvania State
University, University Park, PA 16802 United States
AU: Joughin, I
EM: ian@apl.washington.edu
AF: Department of Earth and Space Sciences, University of Washington, Seattle, WA 98195 United States
AB:
The grounding lines of ice streams are zones of particular interest because of the sensitivity of their position to the size
of the ice shelf beyond. Grounding line retreat rates along the Siple Coast of
Antarctica are poorly known, but crucial to a fuller understanding of
the history and stability of the ice sheet. We describe the results
of a joint GPS and ice-penetrating radar study at the grounding line
of Whillans Ice Stream, West Antarctica. We compare our current
grounding line location with the results from the IceSAT laser
altimeter and the Radarsat-derived grounding line from the 1997 RAMP
(Radarsat Antarctic Mapping Project) mission.
We conducted a kinematic GPS survey of a deeply-embayed portion of the
grounding line as well as a more-concave stretch of the grounding
line to determine the current grounding line and the height above
floatation of the grounded portion. In addition, we collected
ice-penetrating radar data along those lines to determine ice
thickness and map internal layers across the grounding line.
Finally, we deployed a strain grid across the grounding line to
measure the response of the ice to tidal forcing.
DE: 1827 Glaciology (1863)
DE: 1863 Snow and ice (1827)
SC: Near-Surface Geophysics [NS]
MN: 2005 Joint Assembly