Extreme Waves in the Agulhas Current Region Inferred from SAR Wave Spectra and the SWAN Model
The influence of the Agulhas Current on the wave field is investigated. The study is conducted by performing high resolution spectral wave model simulations with and without ocean currents. The validation of the numerical simulations is performed for the Significant Wave Height (Hs) using all possib...
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ftdoajarticles:oai:doaj.org/article:65e86844c34e43d9bef91fe66357ea41 2024-01-07T09:38:29+01:00 Extreme Waves in the Agulhas Current Region Inferred from SAR Wave Spectra and the SWAN Model Sonia Ponce de León C. Guedes Soares 2021-02-01T00:00:00Z https://doi.org/10.3390/jmse9020153 https://doaj.org/article/65e86844c34e43d9bef91fe66357ea41 EN eng MDPI AG https://www.mdpi.com/2077-1312/9/2/153 https://doaj.org/toc/2077-1312 doi:10.3390/jmse9020153 2077-1312 https://doaj.org/article/65e86844c34e43d9bef91fe66357ea41 Journal of Marine Science and Engineering, Vol 9, Iss 2, p 153 (2021) extreme waves Agulhas Current wave-current interactions SAR wave mode SWAN BFI Naval architecture. Shipbuilding. Marine engineering VM1-989 Oceanography GC1-1581 article 2021 ftdoajarticles https://doi.org/10.3390/jmse9020153 2023-12-10T01:48:46Z The influence of the Agulhas Current on the wave field is investigated. The study is conducted by performing high resolution spectral wave model simulations with and without ocean currents. The validation of the numerical simulations is performed for the Significant Wave Height (Hs) using all possible satellite altimetry data available in the study region for a winter period of 2018. Wave spectra and extreme waves parameters are examined in places where waves and current are aligned in the Agulhas Current. Sentinel-1 (S1) wave mode Synthetic Aperture Radar (SAR) spectra are used to estimate the composites of the Hs and BFI (Benjamin–Feir Index). SAR computed BFI and Hs were compared with the respective composites obtained from the Simulating Waves Nearshore (SWAN) model. From the Hs composites using SAR data and modeled data, it can be concluded that the Hs maxima values are distributed in the Agulhas Current Retroflection (ACR) and also in the southern limit of the domain that is affected by the strong circumpolar winds around Antarctic. In addition, the BFI composites exhibit the highest values in the ACR and some few values are observed in the southern border as occurred with the Hs. The results of this study indicate that there is direct correlation between the Agulhas Current strength, the Hs and the BFI. It was found that the modeled directional wave spectra are broadened when the ocean current is considered in the simulation. The analysis of the modeled wave spectra is performed over eddies, rings and meanders in the Agulhas Current region. The transformation of the wave spectra due to current refraction is discussed based on the numerical simulations. The effect of the Agulhas Current on the spectral shape is explored. The spectral wave energy grows when the wave and the current are aligned, resulting in peaked, elongated and widened spectra. A decrease of the peak period was observed before the occurrence of maximum values of BFI, which characterize abnormal sea states. Article in Journal/Newspaper Antarc* Antarctic Directory of Open Access Journals: DOAJ Articles Antarctic Journal of Marine Science and Engineering 9 2 153 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
extreme waves Agulhas Current wave-current interactions SAR wave mode SWAN BFI Naval architecture. Shipbuilding. Marine engineering VM1-989 Oceanography GC1-1581 |
spellingShingle |
extreme waves Agulhas Current wave-current interactions SAR wave mode SWAN BFI Naval architecture. Shipbuilding. Marine engineering VM1-989 Oceanography GC1-1581 Sonia Ponce de León C. Guedes Soares Extreme Waves in the Agulhas Current Region Inferred from SAR Wave Spectra and the SWAN Model |
topic_facet |
extreme waves Agulhas Current wave-current interactions SAR wave mode SWAN BFI Naval architecture. Shipbuilding. Marine engineering VM1-989 Oceanography GC1-1581 |
description |
The influence of the Agulhas Current on the wave field is investigated. The study is conducted by performing high resolution spectral wave model simulations with and without ocean currents. The validation of the numerical simulations is performed for the Significant Wave Height (Hs) using all possible satellite altimetry data available in the study region for a winter period of 2018. Wave spectra and extreme waves parameters are examined in places where waves and current are aligned in the Agulhas Current. Sentinel-1 (S1) wave mode Synthetic Aperture Radar (SAR) spectra are used to estimate the composites of the Hs and BFI (Benjamin–Feir Index). SAR computed BFI and Hs were compared with the respective composites obtained from the Simulating Waves Nearshore (SWAN) model. From the Hs composites using SAR data and modeled data, it can be concluded that the Hs maxima values are distributed in the Agulhas Current Retroflection (ACR) and also in the southern limit of the domain that is affected by the strong circumpolar winds around Antarctic. In addition, the BFI composites exhibit the highest values in the ACR and some few values are observed in the southern border as occurred with the Hs. The results of this study indicate that there is direct correlation between the Agulhas Current strength, the Hs and the BFI. It was found that the modeled directional wave spectra are broadened when the ocean current is considered in the simulation. The analysis of the modeled wave spectra is performed over eddies, rings and meanders in the Agulhas Current region. The transformation of the wave spectra due to current refraction is discussed based on the numerical simulations. The effect of the Agulhas Current on the spectral shape is explored. The spectral wave energy grows when the wave and the current are aligned, resulting in peaked, elongated and widened spectra. A decrease of the peak period was observed before the occurrence of maximum values of BFI, which characterize abnormal sea states. |
format |
Article in Journal/Newspaper |
author |
Sonia Ponce de León C. Guedes Soares |
author_facet |
Sonia Ponce de León C. Guedes Soares |
author_sort |
Sonia Ponce de León |
title |
Extreme Waves in the Agulhas Current Region Inferred from SAR Wave Spectra and the SWAN Model |
title_short |
Extreme Waves in the Agulhas Current Region Inferred from SAR Wave Spectra and the SWAN Model |
title_full |
Extreme Waves in the Agulhas Current Region Inferred from SAR Wave Spectra and the SWAN Model |
title_fullStr |
Extreme Waves in the Agulhas Current Region Inferred from SAR Wave Spectra and the SWAN Model |
title_full_unstemmed |
Extreme Waves in the Agulhas Current Region Inferred from SAR Wave Spectra and the SWAN Model |
title_sort |
extreme waves in the agulhas current region inferred from sar wave spectra and the swan model |
publisher |
MDPI AG |
publishDate |
2021 |
url |
https://doi.org/10.3390/jmse9020153 https://doaj.org/article/65e86844c34e43d9bef91fe66357ea41 |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
Journal of Marine Science and Engineering, Vol 9, Iss 2, p 153 (2021) |
op_relation |
https://www.mdpi.com/2077-1312/9/2/153 https://doaj.org/toc/2077-1312 doi:10.3390/jmse9020153 2077-1312 https://doaj.org/article/65e86844c34e43d9bef91fe66357ea41 |
op_doi |
https://doi.org/10.3390/jmse9020153 |
container_title |
Journal of Marine Science and Engineering |
container_volume |
9 |
container_issue |
2 |
container_start_page |
153 |
_version_ |
1787423459783999488 |