Source regions of infragravity waves recorded at the bottom of the equatorial Atlantic Ocean, using OBS of the PI‐LAB experiment
Infragravity waves are generated along coasts, and some small fraction of their energy escapes to the open oceans and propagates with little attenuation. Due to the scarcity of deep‐ocean observations of these waves, the mechanism and the extent of the infragravity waves energy leakage from the coas...
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ftnerc:oai:nora.nerc.ac.uk:527935 2023-05-15T13:41:45+02:00 Source regions of infragravity waves recorded at the bottom of the equatorial Atlantic Ocean, using OBS of the PI‐LAB experiment Bogiatzis, P. Karamitrou, A. Ward Neale, J. Harmon, N. Rychert, C. A. Srokosz, M. 2020-06-10 text http://nora.nerc.ac.uk/id/eprint/527935/ https://nora.nerc.ac.uk/id/eprint/527935/1/2019JC015430.pdf https://doi.org/10.1029/2019JC015430 en eng https://nora.nerc.ac.uk/id/eprint/527935/1/2019JC015430.pdf Bogiatzis, P.; Karamitrou, A.; Ward Neale, J.; Harmon, N.; Rychert, C. A.; Srokosz, M. orcid:0000-0002-7347-7411 . 2020 Source regions of infragravity waves recorded at the bottom of the equatorial Atlantic Ocean, using OBS of the PI‐LAB experiment. Journal of Geophysical Research: Oceans, 125 (6), e2019JC015430. https://doi.org/10.1029/2019JC015430 <https://doi.org/10.1029/2019JC015430> cc_by_4 CC-BY Publication - Article PeerReviewed 2020 ftnerc https://doi.org/10.1029/2019JC015430 2023-02-04T19:50:47Z Infragravity waves are generated along coasts, and some small fraction of their energy escapes to the open oceans and propagates with little attenuation. Due to the scarcity of deep‐ocean observations of these waves, the mechanism and the extent of the infragravity waves energy leakage from the coasts remains poorly understood. Understanding the generation and pathways of infragravity wave energy is important among others for understanding the breakup of ice‐shelves and the contamination of high‐resolution satellite radar altimetry measurements of sea level. We examine data from 37 differential pressure gauges of Ocean Bottom Seismometers (OBS) near the equatorial mid‐Atlantic ridge, deployed during the Passive Imaging of the Lithosphere‐Asthenosphere Boundary (PI‐LAB) experiment. We use the beamforming technique to investigate the incoming directions of infragravity waves. Next, we develop a graph‐theory‐based global back‐projection method of noise cross‐correlation function envelopes, which minimizes the effects of array geometry using an adaptive weighting scheme. This approach allows us to locate the sources of the infragravity energy. We assess our observations by comparing to a global model of infragravity wave heights. Our results reveal strong coherent energy from sources and/or reflected phases at the west coast of Africa and some sources from South America. These energy sources are in good agreement with the global infragravity wave model. In addition, we also observe infragravity waves arriving from North America during specific events that mostly occur during October–February 2016. Finally, we find indications of waves that propagate with little attenuation, long distances through sea ice, reflecting off Antarctica. Article in Journal/Newspaper Antarc* Antarctica Ice Shelves Sea ice Natural Environment Research Council: NERC Open Research Archive Mid-Atlantic Ridge Journal of Geophysical Research: Oceans 125 6 |
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Open Polar |
collection |
Natural Environment Research Council: NERC Open Research Archive |
op_collection_id |
ftnerc |
language |
English |
description |
Infragravity waves are generated along coasts, and some small fraction of their energy escapes to the open oceans and propagates with little attenuation. Due to the scarcity of deep‐ocean observations of these waves, the mechanism and the extent of the infragravity waves energy leakage from the coasts remains poorly understood. Understanding the generation and pathways of infragravity wave energy is important among others for understanding the breakup of ice‐shelves and the contamination of high‐resolution satellite radar altimetry measurements of sea level. We examine data from 37 differential pressure gauges of Ocean Bottom Seismometers (OBS) near the equatorial mid‐Atlantic ridge, deployed during the Passive Imaging of the Lithosphere‐Asthenosphere Boundary (PI‐LAB) experiment. We use the beamforming technique to investigate the incoming directions of infragravity waves. Next, we develop a graph‐theory‐based global back‐projection method of noise cross‐correlation function envelopes, which minimizes the effects of array geometry using an adaptive weighting scheme. This approach allows us to locate the sources of the infragravity energy. We assess our observations by comparing to a global model of infragravity wave heights. Our results reveal strong coherent energy from sources and/or reflected phases at the west coast of Africa and some sources from South America. These energy sources are in good agreement with the global infragravity wave model. In addition, we also observe infragravity waves arriving from North America during specific events that mostly occur during October–February 2016. Finally, we find indications of waves that propagate with little attenuation, long distances through sea ice, reflecting off Antarctica. |
format |
Article in Journal/Newspaper |
author |
Bogiatzis, P. Karamitrou, A. Ward Neale, J. Harmon, N. Rychert, C. A. Srokosz, M. |
spellingShingle |
Bogiatzis, P. Karamitrou, A. Ward Neale, J. Harmon, N. Rychert, C. A. Srokosz, M. Source regions of infragravity waves recorded at the bottom of the equatorial Atlantic Ocean, using OBS of the PI‐LAB experiment |
author_facet |
Bogiatzis, P. Karamitrou, A. Ward Neale, J. Harmon, N. Rychert, C. A. Srokosz, M. |
author_sort |
Bogiatzis, P. |
title |
Source regions of infragravity waves recorded at the bottom of the equatorial Atlantic Ocean, using OBS of the PI‐LAB experiment |
title_short |
Source regions of infragravity waves recorded at the bottom of the equatorial Atlantic Ocean, using OBS of the PI‐LAB experiment |
title_full |
Source regions of infragravity waves recorded at the bottom of the equatorial Atlantic Ocean, using OBS of the PI‐LAB experiment |
title_fullStr |
Source regions of infragravity waves recorded at the bottom of the equatorial Atlantic Ocean, using OBS of the PI‐LAB experiment |
title_full_unstemmed |
Source regions of infragravity waves recorded at the bottom of the equatorial Atlantic Ocean, using OBS of the PI‐LAB experiment |
title_sort |
source regions of infragravity waves recorded at the bottom of the equatorial atlantic ocean, using obs of the pi‐lab experiment |
publishDate |
2020 |
url |
http://nora.nerc.ac.uk/id/eprint/527935/ https://nora.nerc.ac.uk/id/eprint/527935/1/2019JC015430.pdf https://doi.org/10.1029/2019JC015430 |
geographic |
Mid-Atlantic Ridge |
geographic_facet |
Mid-Atlantic Ridge |
genre |
Antarc* Antarctica Ice Shelves Sea ice |
genre_facet |
Antarc* Antarctica Ice Shelves Sea ice |
op_relation |
https://nora.nerc.ac.uk/id/eprint/527935/1/2019JC015430.pdf Bogiatzis, P.; Karamitrou, A.; Ward Neale, J.; Harmon, N.; Rychert, C. A.; Srokosz, M. orcid:0000-0002-7347-7411 . 2020 Source regions of infragravity waves recorded at the bottom of the equatorial Atlantic Ocean, using OBS of the PI‐LAB experiment. Journal of Geophysical Research: Oceans, 125 (6), e2019JC015430. https://doi.org/10.1029/2019JC015430 <https://doi.org/10.1029/2019JC015430> |
op_rights |
cc_by_4 |
op_rightsnorm |
CC-BY |
op_doi |
https://doi.org/10.1029/2019JC015430 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
125 |
container_issue |
6 |
_version_ |
1766156890439417856 |