Rapid ice unloading in the Fleming Glacier region, southern Antarctic Peninsula, and its effect on bedrock uplift rates
Rapid regional warming in the Antarctic Peninsula has led to the significant retreat and eventual collapse of several major ice shelves since the 1970s, triggering the subsequent acceleration and thinning of their feeding glaciers. The Wordie Ice Shelf, lying off the west coast of the Antarctic Peni...
Published in: | Earth and Planetary Science Letters |
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Online Access: | https://doi.org/10.1016/j.epsl.2017.06.002 http://ecite.utas.edu.au/118149 |
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ftunivtasecite:oai:ecite.utas.edu.au:118149 2023-05-15T13:42:40+02:00 Rapid ice unloading in the Fleming Glacier region, southern Antarctic Peninsula, and its effect on bedrock uplift rates Zhao, C King, MA Watson, CS Barletta, VR Bordoni, A Dell, M Whitehouse, PL 2017 https://doi.org/10.1016/j.epsl.2017.06.002 http://ecite.utas.edu.au/118149 en eng Elsevier Science Bv http://dx.doi.org/10.1016/j.epsl.2017.06.002 http://purl.org/au-research/grants/arc/FT110100207 Zhao, C and King, MA and Watson, CS and Barletta, VR and Bordoni, A and Dell, M and Whitehouse, PL, Rapid ice unloading in the Fleming Glacier region, southern Antarctic Peninsula, and its effect on bedrock uplift rates, Earth and Planetary Science Letters, 473 pp. 164-176. ISSN 0012-821X (2017) [Refereed Article] http://ecite.utas.edu.au/118149 Earth Sciences Geophysics Geodesy Refereed Article PeerReviewed 2017 ftunivtasecite https://doi.org/10.1016/j.epsl.2017.06.002 2022-08-29T22:17:06Z Rapid regional warming in the Antarctic Peninsula has led to the significant retreat and eventual collapse of several major ice shelves since the 1970s, triggering the subsequent acceleration and thinning of their feeding glaciers. The Wordie Ice Shelf, lying off the west coast of the Antarctic Peninsula, has undergone long-term disintegration since the 1960s with a substantial calving event occurring around 1989, followed by continuous steady retreat and its almost-complete disappearance. The dynamic response of the upstream glaciers to the ice shelf collapse and the response of the solid Earth to the associated mass loss are not fully understood. To quantify the mass loss from the system, we generated a digital elevation model (DEM) using airborne vertical and oblique imagery from 1966 and compared it to a DEM derived from 2008 SPOT data. This analysis reveals lowering over that time of approximately 60 m at the front of Fleming Glacier. Using IceBridge and ICESat-2/GLAS data spanning 2002-2014, we show an increased rate of mean ice-surface lowering, with rates post-2008 more than twice those of 2002-2008. We use these load change data as a basis for the simulation of viscoelastic solid Earth deformation. We subtract modeled elastic deformation rates, and a suite of modeled viscous rates, from GPS-derived three-dimensional bedrock velocities at sites to the south of Fleming Glacier to infer properties of Earth rheology. Assuming the pre-breakup bedrock uplift was positive due to post-Last Glacial Maximum (LGM) ice retreat, our viscoelastic-corrected GPS uplift rates suggest upper mantle viscosities are >2 x 10 19 Pas and likely >2 x 10 20 Pas in this region, 1-2 orders of magnitude greater than previously found for the northern Antarctic Peninsula. Horizontal velocities at the GPS site nearest the Fleming Glacier, after the application of elastic and plate tectonic corrections, point away from Marguerite Bay rather than the present glacier front. This suggests that horizontal motion in the region ... Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Ice Shelf Ice Shelves Wordie Ice Shelf eCite UTAS (University of Tasmania) Antarctic Antarctic Peninsula Fleming Glacier ENVELOPE(-66.183,-66.183,-69.467,-69.467) Marguerite ENVELOPE(141.378,141.378,-66.787,-66.787) Marguerite Bay ENVELOPE(-68.000,-68.000,-68.500,-68.500) The Antarctic Wordie ENVELOPE(-67.500,-67.500,-69.167,-69.167) Wordie Ice Shelf ENVELOPE(-67.750,-67.750,-69.250,-69.250) Earth and Planetary Science Letters 473 164 176 |
institution |
Open Polar |
collection |
eCite UTAS (University of Tasmania) |
op_collection_id |
ftunivtasecite |
language |
English |
topic |
Earth Sciences Geophysics Geodesy |
spellingShingle |
Earth Sciences Geophysics Geodesy Zhao, C King, MA Watson, CS Barletta, VR Bordoni, A Dell, M Whitehouse, PL Rapid ice unloading in the Fleming Glacier region, southern Antarctic Peninsula, and its effect on bedrock uplift rates |
topic_facet |
Earth Sciences Geophysics Geodesy |
description |
Rapid regional warming in the Antarctic Peninsula has led to the significant retreat and eventual collapse of several major ice shelves since the 1970s, triggering the subsequent acceleration and thinning of their feeding glaciers. The Wordie Ice Shelf, lying off the west coast of the Antarctic Peninsula, has undergone long-term disintegration since the 1960s with a substantial calving event occurring around 1989, followed by continuous steady retreat and its almost-complete disappearance. The dynamic response of the upstream glaciers to the ice shelf collapse and the response of the solid Earth to the associated mass loss are not fully understood. To quantify the mass loss from the system, we generated a digital elevation model (DEM) using airborne vertical and oblique imagery from 1966 and compared it to a DEM derived from 2008 SPOT data. This analysis reveals lowering over that time of approximately 60 m at the front of Fleming Glacier. Using IceBridge and ICESat-2/GLAS data spanning 2002-2014, we show an increased rate of mean ice-surface lowering, with rates post-2008 more than twice those of 2002-2008. We use these load change data as a basis for the simulation of viscoelastic solid Earth deformation. We subtract modeled elastic deformation rates, and a suite of modeled viscous rates, from GPS-derived three-dimensional bedrock velocities at sites to the south of Fleming Glacier to infer properties of Earth rheology. Assuming the pre-breakup bedrock uplift was positive due to post-Last Glacial Maximum (LGM) ice retreat, our viscoelastic-corrected GPS uplift rates suggest upper mantle viscosities are >2 x 10 19 Pas and likely >2 x 10 20 Pas in this region, 1-2 orders of magnitude greater than previously found for the northern Antarctic Peninsula. Horizontal velocities at the GPS site nearest the Fleming Glacier, after the application of elastic and plate tectonic corrections, point away from Marguerite Bay rather than the present glacier front. This suggests that horizontal motion in the region ... |
format |
Article in Journal/Newspaper |
author |
Zhao, C King, MA Watson, CS Barletta, VR Bordoni, A Dell, M Whitehouse, PL |
author_facet |
Zhao, C King, MA Watson, CS Barletta, VR Bordoni, A Dell, M Whitehouse, PL |
author_sort |
Zhao, C |
title |
Rapid ice unloading in the Fleming Glacier region, southern Antarctic Peninsula, and its effect on bedrock uplift rates |
title_short |
Rapid ice unloading in the Fleming Glacier region, southern Antarctic Peninsula, and its effect on bedrock uplift rates |
title_full |
Rapid ice unloading in the Fleming Glacier region, southern Antarctic Peninsula, and its effect on bedrock uplift rates |
title_fullStr |
Rapid ice unloading in the Fleming Glacier region, southern Antarctic Peninsula, and its effect on bedrock uplift rates |
title_full_unstemmed |
Rapid ice unloading in the Fleming Glacier region, southern Antarctic Peninsula, and its effect on bedrock uplift rates |
title_sort |
rapid ice unloading in the fleming glacier region, southern antarctic peninsula, and its effect on bedrock uplift rates |
publisher |
Elsevier Science Bv |
publishDate |
2017 |
url |
https://doi.org/10.1016/j.epsl.2017.06.002 http://ecite.utas.edu.au/118149 |
long_lat |
ENVELOPE(-66.183,-66.183,-69.467,-69.467) ENVELOPE(141.378,141.378,-66.787,-66.787) ENVELOPE(-68.000,-68.000,-68.500,-68.500) ENVELOPE(-67.500,-67.500,-69.167,-69.167) ENVELOPE(-67.750,-67.750,-69.250,-69.250) |
geographic |
Antarctic Antarctic Peninsula Fleming Glacier Marguerite Marguerite Bay The Antarctic Wordie Wordie Ice Shelf |
geographic_facet |
Antarctic Antarctic Peninsula Fleming Glacier Marguerite Marguerite Bay The Antarctic Wordie Wordie Ice Shelf |
genre |
Antarc* Antarctic Antarctic Peninsula Ice Shelf Ice Shelves Wordie Ice Shelf |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Ice Shelf Ice Shelves Wordie Ice Shelf |
op_relation |
http://dx.doi.org/10.1016/j.epsl.2017.06.002 http://purl.org/au-research/grants/arc/FT110100207 Zhao, C and King, MA and Watson, CS and Barletta, VR and Bordoni, A and Dell, M and Whitehouse, PL, Rapid ice unloading in the Fleming Glacier region, southern Antarctic Peninsula, and its effect on bedrock uplift rates, Earth and Planetary Science Letters, 473 pp. 164-176. ISSN 0012-821X (2017) [Refereed Article] http://ecite.utas.edu.au/118149 |
op_doi |
https://doi.org/10.1016/j.epsl.2017.06.002 |
container_title |
Earth and Planetary Science Letters |
container_volume |
473 |
container_start_page |
164 |
op_container_end_page |
176 |
_version_ |
1766171040785891328 |