Analysis of ice shelf flexure and its InSAR representation in the grounding zone of the southern McMurdo Ice Shelf
We examine tidal flexure in the grounding zone of the McMurdo Ice Shelf, Antarctica, using a combination of TerraSAR-X repeat-pass radar interferometry, a precise digital elevation model, and GPS ground validation data. Satellite and field data were acquired in tandem between October and December 20...
Published in: | The Cryosphere |
---|---|
Main Authors: | , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Copernicus GmbH
2017
|
Subjects: | |
Online Access: | https://doi.org/10.5194/tc-11-2481-2017 http://ecite.utas.edu.au/122195 |
id |
ftunivtasecite:oai:ecite.utas.edu.au:122195 |
---|---|
record_format |
openpolar |
spelling |
ftunivtasecite:oai:ecite.utas.edu.au:122195 2023-05-15T13:42:40+02:00 Analysis of ice shelf flexure and its InSAR representation in the grounding zone of the southern McMurdo Ice Shelf Rack, W King, MA Marsh, OJ Wild, CT Floricioiu, D 2017 application/pdf https://doi.org/10.5194/tc-11-2481-2017 http://ecite.utas.edu.au/122195 en eng Copernicus GmbH http://ecite.utas.edu.au/122195/1/tc-11-2481-2017.pdf http://dx.doi.org/10.5194/tc-11-2481-2017 http://purl.org/au-research/grants/arc/FT110100207 Rack, W and King, MA and Marsh, OJ and Wild, CT and Floricioiu, D, Analysis of ice shelf flexure and its InSAR representation in the grounding zone of the southern McMurdo Ice Shelf, Cryosphere, 11 pp. 2481-2490. ISSN 1994-0416 (2017) [Refereed Article] http://ecite.utas.edu.au/122195 Earth Sciences Geophysics Geodesy Refereed Article PeerReviewed 2017 ftunivtasecite https://doi.org/10.5194/tc-11-2481-2017 2022-08-30T09:11:42Z We examine tidal flexure in the grounding zone of the McMurdo Ice Shelf, Antarctica, using a combination of TerraSAR-X repeat-pass radar interferometry, a precise digital elevation model, and GPS ground validation data. Satellite and field data were acquired in tandem between October and December 2014. Our GPS data show a horizontal modulation of up to 60 % of the vertical displacement amplitude at tidal periods within a few kilometres of the grounding line. We ascribe the observed oscillatory horizontal motion to varying bending stresses and account for it using a simple elastic beam model. The horizontal surface strain is removed from nine differential interferograms to obtain precise bending curves. They reveal a fixed (as opposed to tidally migrating) grounding-line position and eliminate the possibility of significant upstream bending at this location. The consequence of apparent vertical motion due to uncorrected horizontal strain in interferometric data is a systematic mislocation of the interferometric grounding line by up to the order of one ice thickness, or several hundred metres. While our field site was selected due to its simple boundary conditions and low background velocity, our findings are relevant to other grounding zones studied by satellite interferometry, particularly studies looking at tidally induced velocity changes or interpreting satellite-based flexure profiles. Article in Journal/Newspaper Antarc* Antarctica Ice Shelf McMurdo Ice Shelf eCite UTAS (University of Tasmania) McMurdo Ice Shelf ENVELOPE(166.500,166.500,-78.000,-78.000) The Cryosphere 11 6 2481 2490 |
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 Rack, W King, MA Marsh, OJ Wild, CT Floricioiu, D Analysis of ice shelf flexure and its InSAR representation in the grounding zone of the southern McMurdo Ice Shelf |
topic_facet |
Earth Sciences Geophysics Geodesy |
description |
We examine tidal flexure in the grounding zone of the McMurdo Ice Shelf, Antarctica, using a combination of TerraSAR-X repeat-pass radar interferometry, a precise digital elevation model, and GPS ground validation data. Satellite and field data were acquired in tandem between October and December 2014. Our GPS data show a horizontal modulation of up to 60 % of the vertical displacement amplitude at tidal periods within a few kilometres of the grounding line. We ascribe the observed oscillatory horizontal motion to varying bending stresses and account for it using a simple elastic beam model. The horizontal surface strain is removed from nine differential interferograms to obtain precise bending curves. They reveal a fixed (as opposed to tidally migrating) grounding-line position and eliminate the possibility of significant upstream bending at this location. The consequence of apparent vertical motion due to uncorrected horizontal strain in interferometric data is a systematic mislocation of the interferometric grounding line by up to the order of one ice thickness, or several hundred metres. While our field site was selected due to its simple boundary conditions and low background velocity, our findings are relevant to other grounding zones studied by satellite interferometry, particularly studies looking at tidally induced velocity changes or interpreting satellite-based flexure profiles. |
format |
Article in Journal/Newspaper |
author |
Rack, W King, MA Marsh, OJ Wild, CT Floricioiu, D |
author_facet |
Rack, W King, MA Marsh, OJ Wild, CT Floricioiu, D |
author_sort |
Rack, W |
title |
Analysis of ice shelf flexure and its InSAR representation in the grounding zone of the southern McMurdo Ice Shelf |
title_short |
Analysis of ice shelf flexure and its InSAR representation in the grounding zone of the southern McMurdo Ice Shelf |
title_full |
Analysis of ice shelf flexure and its InSAR representation in the grounding zone of the southern McMurdo Ice Shelf |
title_fullStr |
Analysis of ice shelf flexure and its InSAR representation in the grounding zone of the southern McMurdo Ice Shelf |
title_full_unstemmed |
Analysis of ice shelf flexure and its InSAR representation in the grounding zone of the southern McMurdo Ice Shelf |
title_sort |
analysis of ice shelf flexure and its insar representation in the grounding zone of the southern mcmurdo ice shelf |
publisher |
Copernicus GmbH |
publishDate |
2017 |
url |
https://doi.org/10.5194/tc-11-2481-2017 http://ecite.utas.edu.au/122195 |
long_lat |
ENVELOPE(166.500,166.500,-78.000,-78.000) |
geographic |
McMurdo Ice Shelf |
geographic_facet |
McMurdo Ice Shelf |
genre |
Antarc* Antarctica Ice Shelf McMurdo Ice Shelf |
genre_facet |
Antarc* Antarctica Ice Shelf McMurdo Ice Shelf |
op_relation |
http://ecite.utas.edu.au/122195/1/tc-11-2481-2017.pdf http://dx.doi.org/10.5194/tc-11-2481-2017 http://purl.org/au-research/grants/arc/FT110100207 Rack, W and King, MA and Marsh, OJ and Wild, CT and Floricioiu, D, Analysis of ice shelf flexure and its InSAR representation in the grounding zone of the southern McMurdo Ice Shelf, Cryosphere, 11 pp. 2481-2490. ISSN 1994-0416 (2017) [Refereed Article] http://ecite.utas.edu.au/122195 |
op_doi |
https://doi.org/10.5194/tc-11-2481-2017 |
container_title |
The Cryosphere |
container_volume |
11 |
container_issue |
6 |
container_start_page |
2481 |
op_container_end_page |
2490 |
_version_ |
1766171045971099648 |