Nonlinear Radiating Instability of a Barotropic Eastern Boundary Current
Linear and nonlinear radiating instabilities of an eastern boundary current are studied using a barotropic quasigeostrophic model in an idealized meridional channel. The eastern boundary current is meridionally uniform and produces unstable modes in which long waves are most able to radiate. These l...
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| Format: | Article |
| Language: | en_US |
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American Meteorological Society
2014
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| Online Access: | http://hdl.handle.net/1721.1/85076 https://orcid.org/0000-0003-2431-6838 https://orcid.org/0000-0003-3589-5249 |
| _version_ | 1826213002693574656 |
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| author | Wang, Jinbo Spall, Michael A. Flierl, Glenn Richard Rizzoli, Paola M |
| author2 | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences |
| author_facet | Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Wang, Jinbo Spall, Michael A. Flierl, Glenn Richard Rizzoli, Paola M |
| author_sort | Wang, Jinbo |
| collection | MIT |
| description | Linear and nonlinear radiating instabilities of an eastern boundary current are studied using a barotropic quasigeostrophic model in an idealized meridional channel. The eastern boundary current is meridionally uniform and produces unstable modes in which long waves are most able to radiate. These long radiating modes are easily suppressed by friction because of their small growth rates. However, the long radiating modes can overcome friction by nonlinear energy input transferred from the more unstable trapped mode and play an important role in the energy budget of the boundary current system. The nonlinearly powered long radiating modes take away part of the perturbation energy from the instability origin to the ocean interior. The radiated instabilities can generate zonal striations in the ocean interior that are comparable to features observed in the ocean. Subharmonic instability is identified to be responsible for the nonlinear resonance between the radiating and trapped modes, but more general nonlinear triad interactions are expected to apply in a highly nonlinear environment. |
| first_indexed | 2024-09-23T15:41:34Z |
| format | Article |
| id | mit-1721.1/85076 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T15:41:34Z |
| publishDate | 2014 |
| publisher | American Meteorological Society |
| record_format | dspace |
| spelling | mit-1721.1/850762024-05-15T05:32:30Z Nonlinear Radiating Instability of a Barotropic Eastern Boundary Current Wang, Jinbo Spall, Michael A. Flierl, Glenn Richard Rizzoli, Paola M Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences Woods Hole Oceanographic Institution Wang, Jinbo Flierl, Glenn Richard Rizzoli, Paola M. Linear and nonlinear radiating instabilities of an eastern boundary current are studied using a barotropic quasigeostrophic model in an idealized meridional channel. The eastern boundary current is meridionally uniform and produces unstable modes in which long waves are most able to radiate. These long radiating modes are easily suppressed by friction because of their small growth rates. However, the long radiating modes can overcome friction by nonlinear energy input transferred from the more unstable trapped mode and play an important role in the energy budget of the boundary current system. The nonlinearly powered long radiating modes take away part of the perturbation energy from the instability origin to the ocean interior. The radiated instabilities can generate zonal striations in the ocean interior that are comparable to features observed in the ocean. Subharmonic instability is identified to be responsible for the nonlinear resonance between the radiating and trapped modes, but more general nonlinear triad interactions are expected to apply in a highly nonlinear environment. MIT-WHOI Joint Program in Physical Oceanography MIT Y-S Fellowship United States. National Aeronautics and Space Administration (Grant NNX12AD47G) Grant OCE-0752346 2014-02-24T17:23:50Z 2014-02-24T17:23:50Z 2013-07 2013-03 Article http://purl.org/eprint/type/JournalArticle 0022-3670 1520-0485 http://hdl.handle.net/1721.1/85076 Wang, Jinbo, Michael A. Spall, Glenn R. Flierl, and Paola Malanotte-Rizzoli. “Nonlinear Radiating Instability of a Barotropic Eastern Boundary Current.” J. Phys. Oceanogr. 43, no. 7 (July 2013): 1439–1452. © 2013 American Meteorological Society https://orcid.org/0000-0003-2431-6838 https://orcid.org/0000-0003-3589-5249 en_US http://dx.doi.org/10.1175/JPO-D-12-0174.1 Journal of Physical Oceanography Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Meteorological Society American Meteorological Society |
| spellingShingle | Wang, Jinbo Spall, Michael A. Flierl, Glenn Richard Rizzoli, Paola M Nonlinear Radiating Instability of a Barotropic Eastern Boundary Current |
| title | Nonlinear Radiating Instability of a Barotropic Eastern Boundary Current |
| title_full | Nonlinear Radiating Instability of a Barotropic Eastern Boundary Current |
| title_fullStr | Nonlinear Radiating Instability of a Barotropic Eastern Boundary Current |
| title_full_unstemmed | Nonlinear Radiating Instability of a Barotropic Eastern Boundary Current |
| title_short | Nonlinear Radiating Instability of a Barotropic Eastern Boundary Current |
| title_sort | nonlinear radiating instability of a barotropic eastern boundary current |
| url | http://hdl.handle.net/1721.1/85076 https://orcid.org/0000-0003-2431-6838 https://orcid.org/0000-0003-3589-5249 |
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