Available Potential Energy and Irreversible Mixing in the Meridional Overturning Circulation
Available Potential Energy and Irreversible Mixing in the Meridional Overturning Circulation
复制标题
经向翻转环流中的可用势能与不可逆混合
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
R. W. Griffiths
中科院分区：
文献类型：
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作者：
G. Hughes;A. Hogg;R. W. Griffiths
本文从能量学的观点分析了全球海洋翻转环流。分层湍流的一般框架用于此目的，首先，它突出了可用的势能的重要性，在促进动能的转移到背景势能（定义为无运动的重排状态）。接下来，它表明，这是不同的能量库之间的传输速率是重要的海洋翻转的维护，而不是总的潜在或动能。一系列的数值试验被用来评估哪些能量转移是显着的翻转环流。在稳定状态下，不可逆的diapycnal混合的速率必须平衡的生产可用的势能来源于表面浮力通量。因此，来自表面浮力作用力的可用势能和来自其他来源的动能（如表面风和潮汐，并导致湍流混合）的外部输入都是维持翻转环流所必需的。
The overturning circulation of the global oceans is examined from an energetics viewpoint. A general framework for stratified turbulence is used for this purpose; first, it highlights the importance of available potential energy in facilitating the transfer of kinetic energy to the background potential energy (defined as the adiabatically rearranged state with no motion). Next, it is shown that it is the rate of transfer between different energy reservoirs that is important for the maintenance of the ocean overturning, rather than the total amount of potential or kinetic energy. A series of numerical experiments is used to assess which energy transfers are significant in the overturning circulation. In the steady state, the rate of irreversible diapycnal mixing is necessarily balanced by the production of available potential energy sourced from surface buoyancy fluxes. Thus, the external inputs of available potential energy from surface buoyancy forcing and of kinetic energy from other sources (such as surface winds and tides, and leading to turbulent mixing) are both necessary to maintain the overturning circulation.