Ocean-excited plate waves in the Ross and Pine Island Glacier ice shelves
Abstract Ice shelves play an important role in buttressing land ice from reaching the sea, thus restraining the rate of grounded ice loss. Long-period gravity-wave impacts excite vibrations in ice shelves that can expand pre-existing fractures and trigger iceberg calving. To investigate the spatial...
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Language: | English |
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Cambridge University Press (CUP)
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Online Access: | http://dx.doi.org/10.1017/jog.2018.66 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000667 |
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crcambridgeupr:10.1017/jog.2018.66 2024-06-23T07:47:56+00:00 Ocean-excited plate waves in the Ross and Pine Island Glacier ice shelves CHEN, ZHAO BROMIRSKI, PETER D. GERSTOFT, PETER STEPHEN, RALPH A. WIENS, DOUGLAS A. ASTER, RICHARD C. NYBLADE, ANDREW A. 2018 http://dx.doi.org/10.1017/jog.2018.66 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000667 en eng Cambridge University Press (CUP) http://creativecommons.org/licenses/by-nc-sa/4.0/ Journal of Glaciology volume 64, issue 247, page 730-744 ISSN 0022-1430 1727-5652 journal-article 2018 crcambridgeupr https://doi.org/10.1017/jog.2018.66 2024-06-12T04:01:21Z Abstract Ice shelves play an important role in buttressing land ice from reaching the sea, thus restraining the rate of grounded ice loss. Long-period gravity-wave impacts excite vibrations in ice shelves that can expand pre-existing fractures and trigger iceberg calving. To investigate the spatial amplitude variability and propagation characteristics of these vibrations, a 34-station broadband seismic array was deployed on the Ross Ice Shelf (RIS) from November 2014 to November 2016. Two types of ice-shelf plate waves were identified with beamforming: flexural-gravity waves and extensional Lamb waves. Below 20 mHz, flexural-gravity waves dominate coherent signals across the array and propagate landward from the ice front at close to shallow-water gravity-wave speeds (~70 m s −1 ). In the 20–100 mHz band, extensional Lamb waves dominate and propagate at phase speeds ~3 km s −1 . Flexural-gravity and extensional Lamb waves were also observed by a 5-station broadband seismic array deployed on the Pine Island Glacier (PIG) ice shelf from January 2012 to December 2013, with flexural wave energy, also detected at the PIG in the 20–100 mHz band. Considering the ubiquitous presence of storm activity in the Southern Ocean and the similar observations at both the RIS and the PIG ice shelves, it is likely that most, if not all, West Antarctic ice shelves are subjected to similar gravity-wave excitation. Article in Journal/Newspaper Antarc* Antarctic Ice Shelf Ice Shelves Iceberg* Journal of Glaciology Pine Island Glacier Ross Ice Shelf Southern Ocean Cambridge University Press Antarctic Southern Ocean Ross Ice Shelf Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) Journal of Glaciology 64 247 730 744 |
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Open Polar |
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Cambridge University Press |
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crcambridgeupr |
language |
English |
description |
Abstract Ice shelves play an important role in buttressing land ice from reaching the sea, thus restraining the rate of grounded ice loss. Long-period gravity-wave impacts excite vibrations in ice shelves that can expand pre-existing fractures and trigger iceberg calving. To investigate the spatial amplitude variability and propagation characteristics of these vibrations, a 34-station broadband seismic array was deployed on the Ross Ice Shelf (RIS) from November 2014 to November 2016. Two types of ice-shelf plate waves were identified with beamforming: flexural-gravity waves and extensional Lamb waves. Below 20 mHz, flexural-gravity waves dominate coherent signals across the array and propagate landward from the ice front at close to shallow-water gravity-wave speeds (~70 m s −1 ). In the 20–100 mHz band, extensional Lamb waves dominate and propagate at phase speeds ~3 km s −1 . Flexural-gravity and extensional Lamb waves were also observed by a 5-station broadband seismic array deployed on the Pine Island Glacier (PIG) ice shelf from January 2012 to December 2013, with flexural wave energy, also detected at the PIG in the 20–100 mHz band. Considering the ubiquitous presence of storm activity in the Southern Ocean and the similar observations at both the RIS and the PIG ice shelves, it is likely that most, if not all, West Antarctic ice shelves are subjected to similar gravity-wave excitation. |
format |
Article in Journal/Newspaper |
author |
CHEN, ZHAO BROMIRSKI, PETER D. GERSTOFT, PETER STEPHEN, RALPH A. WIENS, DOUGLAS A. ASTER, RICHARD C. NYBLADE, ANDREW A. |
spellingShingle |
CHEN, ZHAO BROMIRSKI, PETER D. GERSTOFT, PETER STEPHEN, RALPH A. WIENS, DOUGLAS A. ASTER, RICHARD C. NYBLADE, ANDREW A. Ocean-excited plate waves in the Ross and Pine Island Glacier ice shelves |
author_facet |
CHEN, ZHAO BROMIRSKI, PETER D. GERSTOFT, PETER STEPHEN, RALPH A. WIENS, DOUGLAS A. ASTER, RICHARD C. NYBLADE, ANDREW A. |
author_sort |
CHEN, ZHAO |
title |
Ocean-excited plate waves in the Ross and Pine Island Glacier ice shelves |
title_short |
Ocean-excited plate waves in the Ross and Pine Island Glacier ice shelves |
title_full |
Ocean-excited plate waves in the Ross and Pine Island Glacier ice shelves |
title_fullStr |
Ocean-excited plate waves in the Ross and Pine Island Glacier ice shelves |
title_full_unstemmed |
Ocean-excited plate waves in the Ross and Pine Island Glacier ice shelves |
title_sort |
ocean-excited plate waves in the ross and pine island glacier ice shelves |
publisher |
Cambridge University Press (CUP) |
publishDate |
2018 |
url |
http://dx.doi.org/10.1017/jog.2018.66 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143018000667 |
long_lat |
ENVELOPE(-101.000,-101.000,-75.000,-75.000) |
geographic |
Antarctic Southern Ocean Ross Ice Shelf Pine Island Glacier |
geographic_facet |
Antarctic Southern Ocean Ross Ice Shelf Pine Island Glacier |
genre |
Antarc* Antarctic Ice Shelf Ice Shelves Iceberg* Journal of Glaciology Pine Island Glacier Ross Ice Shelf Southern Ocean |
genre_facet |
Antarc* Antarctic Ice Shelf Ice Shelves Iceberg* Journal of Glaciology Pine Island Glacier Ross Ice Shelf Southern Ocean |
op_source |
Journal of Glaciology volume 64, issue 247, page 730-744 ISSN 0022-1430 1727-5652 |
op_rights |
http://creativecommons.org/licenses/by-nc-sa/4.0/ |
op_doi |
https://doi.org/10.1017/jog.2018.66 |
container_title |
Journal of Glaciology |
container_volume |
64 |
container_issue |
247 |
container_start_page |
730 |
op_container_end_page |
744 |
_version_ |
1802638213251072000 |