On the propagation of acoustic-gravity waves under elastic ice sheets
The propagation of wave disturbances in water of varying depth bounded above by ice sheets is discussed, accounting for gravity, compressibility and elasticity effects. Considering the more realistic scenario of elastic ice sheets reveals a continuous spectrum of acoustic–gravity modes that propagat...
Published in: | Journal of Fluid Mechanics |
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Language: | English |
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Cambridge University Press (CUP)
2018
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Online Access: | https://orca.cardiff.ac.uk/id/eprint/118857/ https://doi.org/10.1017/jfm.2017.808 https://orca.cardiff.ac.uk/id/eprint/118857/1/Submitted%20revised%20JFM.pdf |
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ftunivcardiff:oai:https://orca.cardiff.ac.uk:118857 2023-05-15T16:40:28+02:00 On the propagation of acoustic-gravity waves under elastic ice sheets Abdolali, Ali Kadri, Usama Parsons, Wade Kirby, James T. 2018-02-25 application/pdf https://orca.cardiff.ac.uk/id/eprint/118857/ https://doi.org/10.1017/jfm.2017.808 https://orca.cardiff.ac.uk/id/eprint/118857/1/Submitted%20revised%20JFM.pdf en eng Cambridge University Press (CUP) https://orca.cardiff.ac.uk/id/eprint/118857/1/Submitted%20revised%20JFM.pdf Abdolali, Ali, Kadri, Usama https://orca.cardiff.ac.uk/view/cardiffauthors/A2268164Q.html orcid:0000-0002-5441-1812 orcid:0000-0002-5441-1812, Parsons, Wade and Kirby, James T. 2018. On the propagation of acoustic-gravity waves under elastic ice sheets. Journal of Fluid Mechanics 837 , pp. 640-656. 10.1017/jfm.2017.808 https://doi.org/10.1017/jfm.2017.808 file https://orca.cardiff.ac.uk/id/eprint/118857/1/Submitted%20revised%20JFM.pdf doi:10.1017/jfm.2017.808 Article PeerReviewed 2018 ftunivcardiff https://doi.org/10.1017/jfm.2017.808 2022-10-27T22:46:32Z The propagation of wave disturbances in water of varying depth bounded above by ice sheets is discussed, accounting for gravity, compressibility and elasticity effects. Considering the more realistic scenario of elastic ice sheets reveals a continuous spectrum of acoustic–gravity modes that propagate even below the cutoff frequency of the rigid surface solution where surface (gravity) waves cannot exist. The balance between gravitational forces and oscillations in the ice sheet defines a new dimensionless quantity Ka. When the ice sheet is relatively thin and the prescribed frequency is relatively low (Ka≪1), the free-surface bottom-pressure solution is retrieved in full. However, thicker ice sheets or propagation of relatively higher frequency modes (Ka≫1) alter the solution fundamentally, which is reflected in an amplified asymmetric signature and different characteristics of the eigenvalues, such that the bottom pressure is amplified when acoustic–gravity waves are transmitted to shallower waters. To analyse these scenarios, an analytical solution and a depth-integrated equation are derived for the cases of constant and varying depths, respectively. Together, these are capable of modelling realistic ocean geometries and an inhomogeneous distribution of ice sheets. Article in Journal/Newspaper Ice Sheet Cardiff University: ORCA (Online Research @ Cardiff) Journal of Fluid Mechanics 837 640 656 |
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Open Polar |
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Cardiff University: ORCA (Online Research @ Cardiff) |
op_collection_id |
ftunivcardiff |
language |
English |
description |
The propagation of wave disturbances in water of varying depth bounded above by ice sheets is discussed, accounting for gravity, compressibility and elasticity effects. Considering the more realistic scenario of elastic ice sheets reveals a continuous spectrum of acoustic–gravity modes that propagate even below the cutoff frequency of the rigid surface solution where surface (gravity) waves cannot exist. The balance between gravitational forces and oscillations in the ice sheet defines a new dimensionless quantity Ka. When the ice sheet is relatively thin and the prescribed frequency is relatively low (Ka≪1), the free-surface bottom-pressure solution is retrieved in full. However, thicker ice sheets or propagation of relatively higher frequency modes (Ka≫1) alter the solution fundamentally, which is reflected in an amplified asymmetric signature and different characteristics of the eigenvalues, such that the bottom pressure is amplified when acoustic–gravity waves are transmitted to shallower waters. To analyse these scenarios, an analytical solution and a depth-integrated equation are derived for the cases of constant and varying depths, respectively. Together, these are capable of modelling realistic ocean geometries and an inhomogeneous distribution of ice sheets. |
format |
Article in Journal/Newspaper |
author |
Abdolali, Ali Kadri, Usama Parsons, Wade Kirby, James T. |
spellingShingle |
Abdolali, Ali Kadri, Usama Parsons, Wade Kirby, James T. On the propagation of acoustic-gravity waves under elastic ice sheets |
author_facet |
Abdolali, Ali Kadri, Usama Parsons, Wade Kirby, James T. |
author_sort |
Abdolali, Ali |
title |
On the propagation of acoustic-gravity waves under elastic ice sheets |
title_short |
On the propagation of acoustic-gravity waves under elastic ice sheets |
title_full |
On the propagation of acoustic-gravity waves under elastic ice sheets |
title_fullStr |
On the propagation of acoustic-gravity waves under elastic ice sheets |
title_full_unstemmed |
On the propagation of acoustic-gravity waves under elastic ice sheets |
title_sort |
on the propagation of acoustic-gravity waves under elastic ice sheets |
publisher |
Cambridge University Press (CUP) |
publishDate |
2018 |
url |
https://orca.cardiff.ac.uk/id/eprint/118857/ https://doi.org/10.1017/jfm.2017.808 https://orca.cardiff.ac.uk/id/eprint/118857/1/Submitted%20revised%20JFM.pdf |
genre |
Ice Sheet |
genre_facet |
Ice Sheet |
op_relation |
https://orca.cardiff.ac.uk/id/eprint/118857/1/Submitted%20revised%20JFM.pdf Abdolali, Ali, Kadri, Usama https://orca.cardiff.ac.uk/view/cardiffauthors/A2268164Q.html orcid:0000-0002-5441-1812 orcid:0000-0002-5441-1812, Parsons, Wade and Kirby, James T. 2018. On the propagation of acoustic-gravity waves under elastic ice sheets. Journal of Fluid Mechanics 837 , pp. 640-656. 10.1017/jfm.2017.808 https://doi.org/10.1017/jfm.2017.808 file https://orca.cardiff.ac.uk/id/eprint/118857/1/Submitted%20revised%20JFM.pdf doi:10.1017/jfm.2017.808 |
op_doi |
https://doi.org/10.1017/jfm.2017.808 |
container_title |
Journal of Fluid Mechanics |
container_volume |
837 |
container_start_page |
640 |
op_container_end_page |
656 |
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1766030866396479488 |