Frequency Downshifting in Wave Spectra in Coastal Zone and Its Influence on Mudbank Formation
The evolution of wind waves in coastal zones leads to changes in the shape of the wave spectrum. Along the coast of Kerala, due to the presence of mudbanks during the southwest monsoon, we could observe downshifting of the peak frequency in the wave spectral data. The present study aims at proving t...
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MDPI AG
2020-09-01
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| Series: | Journal of Marine Science and Engineering |
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| Online Access: | https://www.mdpi.com/2077-1312/8/9/723 |
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| author | Yana Saprykina Margarita Shtremel Samiksha Volvaiker Sergey Kuznetsov |
| author_facet | Yana Saprykina Margarita Shtremel Samiksha Volvaiker Sergey Kuznetsov |
| author_sort | Yana Saprykina |
| collection | DOAJ |
| description | The evolution of wind waves in coastal zones leads to changes in the shape of the wave spectrum. Along the coast of Kerala, due to the presence of mudbanks during the southwest monsoon, we could observe downshifting of the peak frequency in the wave spectral data. The present study aims at proving the mechanism of frequency downshifting and possible influence of the downshifting process on mudbank formation. The results of SWASH (Simulating WAves till SHore) modeling and bispectral analysis shows that frequency downshifting occurs due to the difference nonlinear triad interactions of the main frequency peak of the wave spectrum with frequencies of the infragravity range independent of the viscosity of the medium. The increase in wave dissipation accelerates frequency downshifting additionally, decreasing the wave energy in the main peak frequency. It is shown that frequency downshifting can be one of the possible wave mechanisms of mudbank formation due to essentially different wave attenuation coefficients at the beginning and end of this process. For muddy cohesive sediments, it will lead to formation with an erosive profile at first and then an accumulative profile, i.e., mudbank formation. |
| first_indexed | 2024-03-10T16:12:33Z |
| format | Article |
| id | doaj.art-6278183076ac4bffa0fc0ef24b2322ac |
| institution | Directory Open Access Journal |
| issn | 2077-1312 |
| language | English |
| last_indexed | 2024-03-10T16:12:33Z |
| publishDate | 2020-09-01 |
| publisher | MDPI AG |
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| series | Journal of Marine Science and Engineering |
| spelling | doaj.art-6278183076ac4bffa0fc0ef24b2322ac2023-11-20T14:18:22ZengMDPI AGJournal of Marine Science and Engineering2077-13122020-09-018972310.3390/jmse8090723Frequency Downshifting in Wave Spectra in Coastal Zone and Its Influence on Mudbank FormationYana Saprykina0Margarita Shtremel1Samiksha Volvaiker2Sergey Kuznetsov3Shirshov Institute of Oceanology, Russian Academy of Sciences, 36, Nahimovskiy Prospect, 117997 Moscow, RussiaShirshov Institute of Oceanology, Russian Academy of Sciences, 36, Nahimovskiy Prospect, 117997 Moscow, RussiaCSIR-National Institute of Oceanography, Dona Paula, Goa 403 004, IndiaShirshov Institute of Oceanology, Russian Academy of Sciences, 36, Nahimovskiy Prospect, 117997 Moscow, RussiaThe evolution of wind waves in coastal zones leads to changes in the shape of the wave spectrum. Along the coast of Kerala, due to the presence of mudbanks during the southwest monsoon, we could observe downshifting of the peak frequency in the wave spectral data. The present study aims at proving the mechanism of frequency downshifting and possible influence of the downshifting process on mudbank formation. The results of SWASH (Simulating WAves till SHore) modeling and bispectral analysis shows that frequency downshifting occurs due to the difference nonlinear triad interactions of the main frequency peak of the wave spectrum with frequencies of the infragravity range independent of the viscosity of the medium. The increase in wave dissipation accelerates frequency downshifting additionally, decreasing the wave energy in the main peak frequency. It is shown that frequency downshifting can be one of the possible wave mechanisms of mudbank formation due to essentially different wave attenuation coefficients at the beginning and end of this process. For muddy cohesive sediments, it will lead to formation with an erosive profile at first and then an accumulative profile, i.e., mudbank formation.https://www.mdpi.com/2077-1312/8/9/723frequency downshiftingnonlinear wave transformationwave spectrumSWASH modelbispectral analysismudbank |
| spellingShingle | Yana Saprykina Margarita Shtremel Samiksha Volvaiker Sergey Kuznetsov Frequency Downshifting in Wave Spectra in Coastal Zone and Its Influence on Mudbank Formation Journal of Marine Science and Engineering frequency downshifting nonlinear wave transformation wave spectrum SWASH model bispectral analysis mudbank |
| title | Frequency Downshifting in Wave Spectra in Coastal Zone and Its Influence on Mudbank Formation |
| title_full | Frequency Downshifting in Wave Spectra in Coastal Zone and Its Influence on Mudbank Formation |
| title_fullStr | Frequency Downshifting in Wave Spectra in Coastal Zone and Its Influence on Mudbank Formation |
| title_full_unstemmed | Frequency Downshifting in Wave Spectra in Coastal Zone and Its Influence on Mudbank Formation |
| title_short | Frequency Downshifting in Wave Spectra in Coastal Zone and Its Influence on Mudbank Formation |
| title_sort | frequency downshifting in wave spectra in coastal zone and its influence on mudbank formation |
| topic | frequency downshifting nonlinear wave transformation wave spectrum SWASH model bispectral analysis mudbank |
| url | https://www.mdpi.com/2077-1312/8/9/723 |
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