Ocean-excited plate waves in the Ross and Pine Island Glacier ice shelves
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...
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Cambridge University Press
2018
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Online Access: | https://doi.org/10.1017/jog.2018.66 https://doaj.org/article/4670a4ece2544c488572411b813fe74e |
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ftdoajarticles:oai:doaj.org/article:4670a4ece2544c488572411b813fe74e 2023-05-15T13:47:24+02:00 Ocean-excited plate waves in the Ross and Pine Island Glacier ice shelves ZHAO CHEN PETER D. BROMIRSKI PETER GERSTOFT RALPH A. STEPHEN DOUGLAS A. WIENS RICHARD C. ASTER ANDREW A. NYBLADE 2018-10-01T00:00:00Z https://doi.org/10.1017/jog.2018.66 https://doaj.org/article/4670a4ece2544c488572411b813fe74e EN eng Cambridge University Press https://www.cambridge.org/core/product/identifier/S0022143018000667/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2018.66 0022-1430 1727-5652 https://doaj.org/article/4670a4ece2544c488572411b813fe74e Journal of Glaciology, Vol 64, Pp 730-744 (2018) beamforming cross-correlation flexural-gravity waves ice/ocean interactions ice shelves particle motion plate waves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 article 2018 ftdoajarticles https://doi.org/10.1017/jog.2018.66 2023-03-12T01:30:59Z 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 Directory of Open Access Journals: DOAJ Articles Antarctic Pine Island Glacier ENVELOPE(-101.000,-101.000,-75.000,-75.000) Ross Ice Shelf Southern Ocean Journal of Glaciology 64 247 730 744 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
beamforming cross-correlation flexural-gravity waves ice/ocean interactions ice shelves particle motion plate waves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
spellingShingle |
beamforming cross-correlation flexural-gravity waves ice/ocean interactions ice shelves particle motion plate waves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 ZHAO CHEN PETER D. BROMIRSKI PETER GERSTOFT RALPH A. STEPHEN DOUGLAS A. WIENS RICHARD C. ASTER ANDREW A. NYBLADE Ocean-excited plate waves in the Ross and Pine Island Glacier ice shelves |
topic_facet |
beamforming cross-correlation flexural-gravity waves ice/ocean interactions ice shelves particle motion plate waves Environmental sciences GE1-350 Meteorology. Climatology QC851-999 |
description |
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 |
ZHAO CHEN PETER D. BROMIRSKI PETER GERSTOFT RALPH A. STEPHEN DOUGLAS A. WIENS RICHARD C. ASTER ANDREW A. NYBLADE |
author_facet |
ZHAO CHEN PETER D. BROMIRSKI PETER GERSTOFT RALPH A. STEPHEN DOUGLAS A. WIENS RICHARD C. ASTER ANDREW A. NYBLADE |
author_sort |
ZHAO CHEN |
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 |
publishDate |
2018 |
url |
https://doi.org/10.1017/jog.2018.66 https://doaj.org/article/4670a4ece2544c488572411b813fe74e |
long_lat |
ENVELOPE(-101.000,-101.000,-75.000,-75.000) |
geographic |
Antarctic Pine Island Glacier Ross Ice Shelf Southern Ocean |
geographic_facet |
Antarctic Pine Island Glacier Ross Ice Shelf Southern Ocean |
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, Vol 64, Pp 730-744 (2018) |
op_relation |
https://www.cambridge.org/core/product/identifier/S0022143018000667/type/journal_article https://doaj.org/toc/0022-1430 https://doaj.org/toc/1727-5652 doi:10.1017/jog.2018.66 0022-1430 1727-5652 https://doaj.org/article/4670a4ece2544c488572411b813fe74e |
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_ |
1766247079883046912 |