Material Transport in Oceanic Gyres. Part III: Randomized Stochastic Models
Material Transport in Oceanic Gyres. Part III: Randomized Stochastic Models
复制标题
海洋环流中的物质运输。
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
J. McWilliams
中科院分区：
文献类型：
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作者：
P. Berloff;J. McWilliams
摘要输运模式是通过中尺度涡旋模拟亚网格尺度输运所必需的，而在海洋环流的粗网格表示中通常不能解决这一问题。本文从一类随机模型出发，建立了一种新的输运模型，并用海洋环流的涡旋分解解检验了它的性能。新方法通过扩大模拟运动的范围并允许从一种运动类型转换到另一种运动类型来克服标准马尔可夫模型的缺点。随机输运模型产生了单个被动粒子的随机运动，粒子群的概率密度函数可以解释为被动示踪剂的浓度。这些模型是用来模拟在相干流体结构存在的情况下观察到的湍流物质输运的，并且它们只使用很少的内部参数来表征特定类型的湍流。引入了随机随机化的思想。
Abstract Transport models are required for simulating the subgrid-scale transport by mesoscale eddies, which are typically not resolved in coarse-grid representations of the ocean circulation. Here, a new transport model from the class of stochastic models is formulated and its performance is tested against an eddy-resolving solution of the ocean circulation. The new approach overcomes drawbacks of the standard Markov models by broadening the range of simulated motions and by allowing transitions from one type of motion to another. The stochastic transport models yield random motion of individual passive particles, and the probability density function of the particle population may be interpreted as the concentration of a passive tracer. The models are developed for simulating observed transports of material by turbulent flows in the presence of coherent fluid structures, and they use only few internal parameters characterizing particular type of turbulence. The idea of stochastic randomization is introdu...