Modified (hyper-)viscosity for coarse-resolution ocean models

Louis Thiry; Long Li; Etienne Mémin

doi:10.1007/978-3-031-18988-3_17

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arXiv · 2204.13914

Modified (hyper-)viscosity for coarse-resolution ocean models

Louis Thiry·Long Li·Etienne Mémin

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Abstract

We present a simple parameterization for coarse-resolution ocean models. To replace computationally expensive high-resolution ocean models, we develop a computationally cheap parameterization for coarse-resolution models based solely on the modification of the viscosity term in advection equations. It is meant to reproduce the mean quantities like pressure, velocity, or vorticity computed from a high-resolution reference solution or using observations. We test this new parameterization on a double-gyre quasi-geostrophic model in the eddy-permitting regime. Our results show that the proposed scheme improves significantly the energy statistics and the intrinsic variability on the coarse mesh. This method shall serve as a deterministic basis model for coarse-resolution stochastic parameterizations in future works.

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BibTeX RIS

Louis Thiry, Long Li, Etienne Mémin. 2022-04-29. Modified (hyper-)viscosity for coarse-resolution ocean models. https://doi.org/10.1007/978-3-031-18988-3_17

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