Shear and Convective Turbulence in a Model of Thermohaline Intrusions
Shear and Convective Turbulence in a Model of Thermohaline Intrusions
复制标题
温盐侵入模型中的剪切和对流湍流
DOI：
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发表时间：
2007
期刊：
影响因子：
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通讯作者：
B. Ruddick
中科院分区：
文献类型：
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作者：
Rachael D. Mueller;W. Smyth;B. Ruddick
摘要温盐交错是水团间盐、热、营养物质横向流动的重要机制。交错是由海水中热量和盐份的不同扩散率导致的势能释放驱动的。这些水流是由堆叠的侵入体组成的，它们以相反的方向流动着更多和更少的浮力水。在本文中，剪切不稳定所造成的这种并列运动的作用进行了研究。对沃尔什和鲁迪克的模型进行了修改，使其既包括剪切诱导湍流的影响，又包括改进的对流混合参数化。剪切和对流混合在交错动力学中起着类似的重要作用。在没有任何不稳定性的情况下，交叉锋通量增加约30%。虽然在原位观测的水平扩散率产生的交错尚未精确到足以独立校准的参数化，参数值的基础上，独立的实验室和数量。
Abstract Thermohaline interleaving is an important mechanism for laterally fluxing salt, heat, and nutrients between water masses. Interleaving is driven by a release of potential energy resulting from the differing diffusivities of heat and salt in seawater. The flows are composed of stacked intrusions that flux more and less buoyant water in opposite directions. In this paper, the role of shear instability caused by this juxtaposed motion is investigated. The model described in Walsh and Ruddick is modified to include both the effects of shear-induced turbulence and an improved convective mixing parameterization. Shear and convective mixing play a similar and significant role in interleaving dynamics. In the absence of either instability, cross-front fluxes are increased by approximately 30%. While in situ observations of horizontal diffusivity resulting from interleaving are not yet precise enough to calibrate the parameterizations independently, parameter values based on independent laboratory and num...