Tidally driven stick-slip motion in the mouth of Whillans Ice Stream, Antarctica
We show that the ice plain in the mouth of Whillans Ice Stream (formerly Ice Stream B), Antarctica, moves by stick-slip motion. During a spring-tide period, rapid motions regularly occur near high tide and during falling tide. This correlation is weaker during a neap-tide period when the tidal magni...
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ftunivtasecite:oai:ecite.utas.edu.au:81800 2023-05-15T13:29:38+02:00 Tidally driven stick-slip motion in the mouth of Whillans Ice Stream, Antarctica Bindschadler, RA Vornberger, PL King, MA Padman, L 2003 http://ecite.utas.edu.au/81800 en eng x Bindschadler, RA and Vornberger, PL and King, MA and Padman, L, Tidally driven stick-slip motion in the mouth of Whillans Ice Stream, Antarctica, Annals of Glaciology, 36 pp. 263-272. ISSN 0260-3055 (2003) [Refereed Article] http://ecite.utas.edu.au/81800 Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified Refereed Article PeerReviewed 2003 ftunivtasecite 2019-12-13T21:46:50Z We show that the ice plain in the mouth of Whillans Ice Stream (formerly Ice Stream B), Antarctica, moves by stick-slip motion. During a spring-tide period, rapid motions regularly occur near high tide and during falling tide. This correlation is weaker during a neap-tide period when the tidal magnitudes are less. Precise timing of these motion events suggests that they propagate through the region with a mean velocity of 88 ms-1. We hypothesize that this speed is associated with the propagation of shear waves through a wet subglacial till. Motion events are also seen on more smoothly flowing floating ice. Event delays are very short between grounded and floating stations, suggesting the events propagate through the ice shelf as an elastic wave. We further hypothesize the events are caused by the interaction of a sticky bed, the accumulation of stored elastic strain through the compression of ice by upstream inflow, and tidal forcing. Motion events seem to be triggered either by reduction of vertical normal stresses at high tide or by the increase of shear stresses from sub-shelf ocean currents during falling tide. Event magnitudes are not related to the length of the preceding quiescent period, suggesting significant viscous dissipation within the till. Article in Journal/Newspaper Annals of Glaciology Antarc* Antarctica Ice Shelf Ice Stream B Whillans Ice Stream eCite UTAS (University of Tasmania) Whillans ENVELOPE(-64.250,-64.250,-84.450,-84.450) Whillans Ice Stream ENVELOPE(-145.000,-145.000,-83.667,-83.667) |
institution |
Open Polar |
collection |
eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified |
spellingShingle |
Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified Bindschadler, RA Vornberger, PL King, MA Padman, L Tidally driven stick-slip motion in the mouth of Whillans Ice Stream, Antarctica |
topic_facet |
Earth Sciences Physical Geography and Environmental Geoscience Physical Geography and Environmental Geoscience not elsewhere classified |
description |
We show that the ice plain in the mouth of Whillans Ice Stream (formerly Ice Stream B), Antarctica, moves by stick-slip motion. During a spring-tide period, rapid motions regularly occur near high tide and during falling tide. This correlation is weaker during a neap-tide period when the tidal magnitudes are less. Precise timing of these motion events suggests that they propagate through the region with a mean velocity of 88 ms-1. We hypothesize that this speed is associated with the propagation of shear waves through a wet subglacial till. Motion events are also seen on more smoothly flowing floating ice. Event delays are very short between grounded and floating stations, suggesting the events propagate through the ice shelf as an elastic wave. We further hypothesize the events are caused by the interaction of a sticky bed, the accumulation of stored elastic strain through the compression of ice by upstream inflow, and tidal forcing. Motion events seem to be triggered either by reduction of vertical normal stresses at high tide or by the increase of shear stresses from sub-shelf ocean currents during falling tide. Event magnitudes are not related to the length of the preceding quiescent period, suggesting significant viscous dissipation within the till. |
format |
Article in Journal/Newspaper |
author |
Bindschadler, RA Vornberger, PL King, MA Padman, L |
author_facet |
Bindschadler, RA Vornberger, PL King, MA Padman, L |
author_sort |
Bindschadler, RA |
title |
Tidally driven stick-slip motion in the mouth of Whillans Ice Stream, Antarctica |
title_short |
Tidally driven stick-slip motion in the mouth of Whillans Ice Stream, Antarctica |
title_full |
Tidally driven stick-slip motion in the mouth of Whillans Ice Stream, Antarctica |
title_fullStr |
Tidally driven stick-slip motion in the mouth of Whillans Ice Stream, Antarctica |
title_full_unstemmed |
Tidally driven stick-slip motion in the mouth of Whillans Ice Stream, Antarctica |
title_sort |
tidally driven stick-slip motion in the mouth of whillans ice stream, antarctica |
publisher |
x |
publishDate |
2003 |
url |
http://ecite.utas.edu.au/81800 |
long_lat |
ENVELOPE(-64.250,-64.250,-84.450,-84.450) ENVELOPE(-145.000,-145.000,-83.667,-83.667) |
geographic |
Whillans Whillans Ice Stream |
geographic_facet |
Whillans Whillans Ice Stream |
genre |
Annals of Glaciology Antarc* Antarctica Ice Shelf Ice Stream B Whillans Ice Stream |
genre_facet |
Annals of Glaciology Antarc* Antarctica Ice Shelf Ice Stream B Whillans Ice Stream |
op_relation |
Bindschadler, RA and Vornberger, PL and King, MA and Padman, L, Tidally driven stick-slip motion in the mouth of Whillans Ice Stream, Antarctica, Annals of Glaciology, 36 pp. 263-272. ISSN 0260-3055 (2003) [Refereed Article] http://ecite.utas.edu.au/81800 |
_version_ |
1766001604343889920 |