Data/hora: 05/06/2024 05:39:20

Provedor de dados: 	5	
País: 	France	
Título: 	A parameterization of local and remote tidal mixing	
Autores: 	Lavergne, C.; Vic, Clement; Madec, G; Roquet, F.; Waterhouse, A. F.; Whalen, C. B.; Cuypers, Y.; Bouruet‐aubertot, P.; Ferron, Bruno; Hibiya, T.	
Data: 	2020	
Ano: 	2020	
Palavras-chave: 	Ocean mixing; Internal tides; Parameterization; Energy dissipation.	
Resumo: 	Vertical mixing is often regarded as the Achilles' heel of ocean models. In particular, few models include a comprehensive and energy‐constrained parameterization of mixing by internal ocean tides. Here, we present an energy‐conserving mixing scheme which accounts for the local breaking of high‐mode internal tides and the distant dissipation of low‐mode internal tides. The scheme relies on four static two‐dimensional maps of internal tide dissipation, constructed using mode‐by‐mode Lagrangian tracking of energy beams from sources to sinks. Each map is associated with a distinct dissipative process and a corresponding vertical structure. Applied to an observational climatology of stratification, the scheme produces a global three‐dimensional map of dissipation which compares well with available microstructure observations and with upper‐ocean finestructure mixing estimates. This relative agreement, both in magnitude and spatial structure across ocean basins, suggests that internal tides underpin most of observed dissipation in the ocean interior at the global scale. The proposed parameterization is therefore expected to improve understanding, mapping and modelling of ocean mixing Plain Language Summary When tidal ocean currents flow over bumpy seafloor, they generate internal tidal waves. Internal waves are the subsurface analogue of surface waves that break on beaches. Like surface waves, internal tidal waves often become unstable and break into turbulence. This turbulence is a primary cause of mixing between stacked ocean layers—a key process regulating ocean currents and biology and a key ingredient of computer models of the global ocean. In this article, a three‐dimensional global map of mixing induced by internal tidal waves is presented. This map incorporates a large variety of energy pathways from the generation of tidal waves to turbulence, accounting for the conservation of energy. The map is compared to available observations of turbulence across the globe and found to reproduce with good fidelity the main patterns identified in observations. This relatively good agreement suggests that internal tidal waves are the main source of turbulence in the subsurface ocean, and implies that the map may serve a range of applications. In particular, the three‐dimensional map provides an efficient and realistic means to represent mixing by internal tidal waves in global ocean models.	
Tipo: 	Text	
Idioma: 	Inglês	
Identificador: 	https://archimer.ifremer.fr/doc/00624/73573/72943.pdf

https://archimer.ifremer.fr/doc/00624/73573/72944.pdf

DOI:10.1029/2020MS002065

https://archimer.ifremer.fr/doc/00624/73573/	
Editor: 	American Geophysical Union (AGU)	
Relação: 	info:eu-repo/grantAgreement/EC/H2020/824084/EU//IS-ENES3

info:eu-repo/grantAgreement/EC/H2020/821001/EU//SO-CHIC	
Formato: 	application/pdf	
Fonte: 	Journal of Advances in Modeling Earth Systems (1942-2466) (American Geophysical Union (AGU)) In Press	
Fonte: 	info:eu-repo/semantics/openAccess

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