Data/hora: 09/06/2024 03:58:20

Provedor de dados: | 5
País: | France
Título: | Effects of the submesoscale on the potential vorticity budget of ocean mode waters
Autores: | Wenegrat, Jacob O.; Thomas, Leif N.; Gula, Jonathan; Mcwilliams, James C.
Data: | 2018-09
Ano: | 2018
Palavras-chave: | Ageostrophic circulations; Atmosphere-ocean interaction; Fronts; Ocean dynamics; Potential vorticity; Boundary layer.
Resumo: | Non-conservative processes change the potential vorticity (PV) of the upper ocean, and later, through the subduction of surface waters into the interior, affect the general ocean circulation. Here we focus on how boundary layer turbulence, in the presence of submesoscale horizontal buoyancy gradients, generates a source of potential vorticity at the ocean surface through a balance known as the Turbulent ThermalWind. This source of PV injection at the submesoscale can be of similar magnitude to PV fluxes from the wind and surface buoyancy fluxes, and hence can lead to a net injection of PV onto outcropped isopycnals even during periods of surface buoyancy loss. The significance of these dynamics is illustrated using a high-resolution realistic model of the North Atlantic Subtropical Mode Water (18° water), where it is demonstrated that injection of PV at the submesoscale reduces the rate of mode-water PV removal by a factor of ~ 2, and shortens the annual period of mode water formation by ~3 weeks, relative to air-sea fluxes alone. Submesoscale processes thus provide a direct link between small-scale boundary layer turbulence and the gyre-scale circulation, through their effect on mode water formation, with implications for understanding the variability and biogeochemical properties of ocean mode waters globally.
Tipo: | Text
Idioma: | Inglês

Identificador:

http://archimer.ifremer.fr/doc/00452/56347/57937.pdf

DOI:10.1175/JPO-D-17-0219.1

http://archimer.ifremer.fr/doc/00452/56347/

Editor: | Amer Meteorological Soc
Formato: | application/pdf
Fonte: | Journal Of Physical Oceanography (0022-3670) (Amer Meteorological Soc), 2018-09 , Vol. 48 , N. 9 , P. 2141-2165

Fonte:

2018 American Meteorological Society

info:eu-repo/semantics/openAccess

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