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- de Lavergne, C., et al.
(författare)
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A Parameterization of Local and Remote Tidal Mixing
- 2020
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Ingår i: Journal of Advances in Modeling Earth Systems. - 1942-2466. ; 12:5
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Tidskriftsartikel (refereegranskat)abstract
- 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 modeling of ocean mixing. ©2020. The Authors.
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| 2. |
- Parard, Gaëlle, et al.
(författare)
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On the physical and biogeochemical processes driving the high frequency variability of CO2 fugacity at 6 degrees S, 10 degrees W : Potential role of the internal waves
- 2014
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Ingår i: JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS. - 2169-9275. ; 119:12, s. 8357-8374
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Tidskriftsartikel (refereegranskat)abstract
- The availability of nutrients in the mixed layer is the main limitation to organic carbon biological production in the tropical regions. In this paper, we investigate the potential role of internal waves at promoting the development of biological activity on a PIRATA mooring at 6 degrees S, 10 degrees W. This mooring is located above the Mid-Atlantic Ridge where we observe strong internal waves. Using a one-dimensional physical and biogeochemical coupled model, we simulate dissolved inorganic carbon (DIC). Providing the influence of vertical advection and turbulent diapycnal diffusivity are (it is vertical advection + turbulent dipycnal mixing) accounted for, we find that this model provides a good fit with observed in situ CO2 fugacity (fCO(2)). Main effect of internal waves is to rapidly increase the DIC, thus the fCO(2) and the nutrients in the mixed layer. The latter induce progressive development of biological activity leading to gradual DIC decrease. Our study highlights the importance of correctly taking into account the effect of internal waves in tropical regions.
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