Flow and retreat of the Late Quaternary Pine Island-Thwaites palaeo-ice stream, West Antarctica
Multibeam swath bathymetry and sub-bottom profiler data are used to establish constraints on the flow and retreat history of a major palaeo-ice stream that carried the combined discharge from the parts of the West Antarctic Ice Sheet now occupied by the Pine Island and Thwaites glacier basins. Sets...
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American Geophysical Union
2010
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Online Access: | http://nora.nerc.ac.uk/id/eprint/11212/ https://nora.nerc.ac.uk/id/eprint/11212/1/jgrf697.pdf https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2009JF001482 |
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ftnerc:oai:nora.nerc.ac.uk:11212 2023-05-15T13:45:10+02:00 Flow and retreat of the Late Quaternary Pine Island-Thwaites palaeo-ice stream, West Antarctica Graham, Alastair G.C. Larter, Robert D. Gohl, Karsten Dowdeswell, Julian A. Hillenbrand, Claus-Dieter Smith, James A. Evans, Jeffrey Kuhn, Gerhard Deen, Tara 2010-09 text http://nora.nerc.ac.uk/id/eprint/11212/ https://nora.nerc.ac.uk/id/eprint/11212/1/jgrf697.pdf https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2009JF001482 en eng American Geophysical Union https://nora.nerc.ac.uk/id/eprint/11212/1/jgrf697.pdf Graham, Alastair G.C.; Larter, Robert D. orcid:0000-0002-8414-7389 Gohl, Karsten; Dowdeswell, Julian A.; Hillenbrand, Claus-Dieter orcid:0000-0003-0240-7317 Smith, James A. orcid:0000-0002-1333-2544 Evans, Jeffrey; Kuhn, Gerhard; Deen, Tara. 2010 Flow and retreat of the Late Quaternary Pine Island-Thwaites palaeo-ice stream, West Antarctica. Journal of Geophysical Research, 115 (F3), F03025. 12, pp. https://doi.org/10.1029/2009JF001482 <https://doi.org/10.1029/2009JF001482> Glaciology Earth Sciences Publication - Article PeerReviewed 2010 ftnerc https://doi.org/10.1029/2009JF001482 2023-02-04T19:27:12Z Multibeam swath bathymetry and sub-bottom profiler data are used to establish constraints on the flow and retreat history of a major palaeo-ice stream that carried the combined discharge from the parts of the West Antarctic Ice Sheet now occupied by the Pine Island and Thwaites glacier basins. Sets of highly elongated bedforms show that, at the last glacial maximum, the route of the Pine Island-Thwaites palaeo-ice stream arced north-northeast following a prominent cross-shelf trough. In this area, the grounding line advanced to within similar to 68 km of, and probably reached, the shelf edge. Minimum ice thickness is estimated at 715 m on the outer shelf, and we estimate a minimum ice discharge of similar to 108 km(3) yr(-1) assuming velocities similar to today's Pine Island glacier (similar to 2.5 km yr(-1)). Additional bed forms observed in a trough northwest of Pine Island Bay likely formed via diachronous ice flows across the outer shelf and demonstrate switching ice stream behavior. The "style" of ice retreat is also evident in five grounding zone wedges, which suggest episodic deglaciation characterized by halts in grounding line migration up-trough. Stillstands occurred in association with changes in ice bed gradient, and phases of inferred rapid retreat correlate to higher bed slopes, supporting theoretical studies that show bed geometry as a control on ice margin recession. However, estimates that individual wedges could have formed within several centuries still imply a relatively rapid overall retreat. Our findings show that the ice stream channeled a substantial fraction of West Antarctica's discharge in the past, just as the Pine Island and Thwaites glaciers do today. Article in Journal/Newspaper Antarc* Antarctic Antarctica Antarctica Journal Ice Sheet Pine Island Pine Island Bay Pine Island Glacier Thwaites Glacier West Antarctica Natural Environment Research Council: NERC Open Research Archive Antarctic Island Bay ENVELOPE(-109.085,-109.085,59.534,59.534) Pine Island Bay ENVELOPE(-102.000,-102.000,-74.750,-74.750) Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) Thwaites Glacier ENVELOPE(-106.750,-106.750,-75.500,-75.500) West Antarctic Ice Sheet West Antarctica Journal of Geophysical Research 115 F3 |
institution |
Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
topic |
Glaciology Earth Sciences |
spellingShingle |
Glaciology Earth Sciences Graham, Alastair G.C. Larter, Robert D. Gohl, Karsten Dowdeswell, Julian A. Hillenbrand, Claus-Dieter Smith, James A. Evans, Jeffrey Kuhn, Gerhard Deen, Tara Flow and retreat of the Late Quaternary Pine Island-Thwaites palaeo-ice stream, West Antarctica |
topic_facet |
Glaciology Earth Sciences |
description |
Multibeam swath bathymetry and sub-bottom profiler data are used to establish constraints on the flow and retreat history of a major palaeo-ice stream that carried the combined discharge from the parts of the West Antarctic Ice Sheet now occupied by the Pine Island and Thwaites glacier basins. Sets of highly elongated bedforms show that, at the last glacial maximum, the route of the Pine Island-Thwaites palaeo-ice stream arced north-northeast following a prominent cross-shelf trough. In this area, the grounding line advanced to within similar to 68 km of, and probably reached, the shelf edge. Minimum ice thickness is estimated at 715 m on the outer shelf, and we estimate a minimum ice discharge of similar to 108 km(3) yr(-1) assuming velocities similar to today's Pine Island glacier (similar to 2.5 km yr(-1)). Additional bed forms observed in a trough northwest of Pine Island Bay likely formed via diachronous ice flows across the outer shelf and demonstrate switching ice stream behavior. The "style" of ice retreat is also evident in five grounding zone wedges, which suggest episodic deglaciation characterized by halts in grounding line migration up-trough. Stillstands occurred in association with changes in ice bed gradient, and phases of inferred rapid retreat correlate to higher bed slopes, supporting theoretical studies that show bed geometry as a control on ice margin recession. However, estimates that individual wedges could have formed within several centuries still imply a relatively rapid overall retreat. Our findings show that the ice stream channeled a substantial fraction of West Antarctica's discharge in the past, just as the Pine Island and Thwaites glaciers do today. |
format |
Article in Journal/Newspaper |
author |
Graham, Alastair G.C. Larter, Robert D. Gohl, Karsten Dowdeswell, Julian A. Hillenbrand, Claus-Dieter Smith, James A. Evans, Jeffrey Kuhn, Gerhard Deen, Tara |
author_facet |
Graham, Alastair G.C. Larter, Robert D. Gohl, Karsten Dowdeswell, Julian A. Hillenbrand, Claus-Dieter Smith, James A. Evans, Jeffrey Kuhn, Gerhard Deen, Tara |
author_sort |
Graham, Alastair G.C. |
title |
Flow and retreat of the Late Quaternary Pine Island-Thwaites palaeo-ice stream, West Antarctica |
title_short |
Flow and retreat of the Late Quaternary Pine Island-Thwaites palaeo-ice stream, West Antarctica |
title_full |
Flow and retreat of the Late Quaternary Pine Island-Thwaites palaeo-ice stream, West Antarctica |
title_fullStr |
Flow and retreat of the Late Quaternary Pine Island-Thwaites palaeo-ice stream, West Antarctica |
title_full_unstemmed |
Flow and retreat of the Late Quaternary Pine Island-Thwaites palaeo-ice stream, West Antarctica |
title_sort |
flow and retreat of the late quaternary pine island-thwaites palaeo-ice stream, west antarctica |
publisher |
American Geophysical Union |
publishDate |
2010 |
url |
http://nora.nerc.ac.uk/id/eprint/11212/ https://nora.nerc.ac.uk/id/eprint/11212/1/jgrf697.pdf https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2009JF001482 |
long_lat |
ENVELOPE(-109.085,-109.085,59.534,59.534) ENVELOPE(-102.000,-102.000,-74.750,-74.750) ENVELOPE(-101.000,-101.000,-75.000,-75.000) ENVELOPE(-106.750,-106.750,-75.500,-75.500) |
geographic |
Antarctic Island Bay Pine Island Bay Pine Island Glacier Thwaites Glacier West Antarctic Ice Sheet West Antarctica |
geographic_facet |
Antarctic Island Bay Pine Island Bay Pine Island Glacier Thwaites Glacier West Antarctic Ice Sheet West Antarctica |
genre |
Antarc* Antarctic Antarctica Antarctica Journal Ice Sheet Pine Island Pine Island Bay Pine Island Glacier Thwaites Glacier West Antarctica |
genre_facet |
Antarc* Antarctic Antarctica Antarctica Journal Ice Sheet Pine Island Pine Island Bay Pine Island Glacier Thwaites Glacier West Antarctica |
op_relation |
https://nora.nerc.ac.uk/id/eprint/11212/1/jgrf697.pdf Graham, Alastair G.C.; Larter, Robert D. orcid:0000-0002-8414-7389 Gohl, Karsten; Dowdeswell, Julian A.; Hillenbrand, Claus-Dieter orcid:0000-0003-0240-7317 Smith, James A. orcid:0000-0002-1333-2544 Evans, Jeffrey; Kuhn, Gerhard; Deen, Tara. 2010 Flow and retreat of the Late Quaternary Pine Island-Thwaites palaeo-ice stream, West Antarctica. Journal of Geophysical Research, 115 (F3), F03025. 12, pp. https://doi.org/10.1029/2009JF001482 <https://doi.org/10.1029/2009JF001482> |
op_doi |
https://doi.org/10.1029/2009JF001482 |
container_title |
Journal of Geophysical Research |
container_volume |
115 |
container_issue |
F3 |
_version_ |
1766214440142766080 |