Statistical dynamical subgrid-scale parameterizations for geophysical flows
Statistical dynamical subgrid-scale parameterizations for geophysical flows
复制标题
地球物理流的统计动力学亚网格尺度参数化
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
J. Frederiksen
中科院分区：
文献类型：
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作者：
Terence J. O’Kane;J. Frederiksen
在给定的有限分辨率的大气和海洋环流的模拟强烈依赖于动态亚网格尺度参数化（SSP）的形式和强度，特别是敏感的亚网格尺度瞬态涡与保留的尺度地形和平均流相互作用。在本文中，我们提出的涡地形力，随机后向散射，涡粘性和涡平均场的相互作用，使用非均匀统计湍流模型的基础上的准对角直接相互作用近似（QDIA）的SSP的数值结果。虽然我们的模型所依据的理论描述是一般的正压气流，我们特别关注全球大气流动的大尺度Rossby波存在。我们比较和对比的封闭为基础的结果与一个重要的早期启发式SSP的涡地形的力量，最大熵或统计正则平衡参数的基础上，专门为一般的海洋环流模型（霍洛威1992年J。22 1033-46）。我们的研究结果表明，强纬向流和Rossby波存在，如在大气中，最大熵参数不足以准确地参数化的亚网格的贡献，由于涡动，涡动地形和涡动平均场的相互作用。我们将我们的大气结果与海洋的发现进行了对比。我们的研究确定了亚网格尺度的相互作用，目前没有参数化的数值大气气候模式，这可能会导致系统性的缺陷，在模拟环流。
Simulations of both atmospheric and oceanic circulations at given finite resolutions are strongly dependent on the form and strengths of the dynamical subgrid-scale parameterizations (SSPs) and in particular are sensitive to subgrid-scale transient eddies interacting with the retained scale topography and the mean flow. In this paper, we present numerical results for SSPs of the eddy–topographic force, stochastic backscatter, eddy viscosity and eddy–mean field interaction using an inhomogeneous statistical turbulence model based on a quasi-diagonal direct interaction approximation (QDIA). Although the theoretical description on which our model is based is for general barotropic flows, we specifically focus on global atmospheric flows where large-scale Rossby waves are present. We compare and contrast the closure-based results with an important earlier heuristic SSP of the eddy–topographic force, based on maximum entropy or statistical canonical equilibrium arguments, developed specifically for general ocean circulation models (Holloway 1992 J. Phys. Oceanogr. 22 1033–46). Our results demonstrate that where strong zonal flows and Rossby waves are present, such as in the atmosphere, maximum entropy arguments are insufficient to accurately parameterize the subgrid contributions due to eddy–eddy, eddy–topographic and eddy–mean field interactions. We contrast our atmospheric results with findings for the oceans. Our study identifies subgrid-scale interactions that are currently not parameterized in numerical atmospheric climate models, which may lead to systematic defects in the simulated circulations.