Smoluchowski coagulation models of sea ice thickness distribution dynamics
Smoluchowski coagulation models of sea ice thickness distribution dynamics
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海冰厚度分布动态的 Smoluchowski 凝固模型
DOI：
10.1029/2011jc007125
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发表时间：
2011
影响因子：
--
通讯作者：
A. Monahan
中科院分区：
文献类型：
--
作者：
D. Godlovitch;R. Illner;A. Monahan
[1]海冰厚度分布显示出普遍存在的指数随厚度减小。这条尾巴表征了冰的厚度范围，这是冰通过脊状、筏状和剪切过程的机械重新分布而产生的。我们调查如何以及厚度分布可以模拟机械再分配作为一个广义的堆叠过程。这样的过程自然地由被称为Smoluchowski凝结模型（SCM）的被充分研究的一类模型描述，其描述固定质量“粒子”的群体的动力学，所述固定质量“粒子”成对地联合收割机以取决于相互作用粒子的质量的速率结合以形成具有组成对的组合质量的“粒子”。与观测到的海冰厚度分布一样，SCMs产生的种群的质量分布具有指数或准指数形式。我们使用SCM海冰模型，确定质量增加的颗粒组合与厚度增加的冰再分配过程。我们的模型耦合SCM组件与热力学组件，并产生定性准确的厚度分布与各种速率内核。我们的研究结果表明，海冰厚度分布的指数尾产生的脊过程的性质，而不是特定的物理性质的海冰或浮冰的空间排列，和动力学和热力学过程的相对强度是关键，准确地模拟率在海冰厚度尾部下降厚度。
[1] Sea ice thickness distributions display a ubiquitous exponential decrease with thickness. This tail characterizes the range of ice thickness produced by mechanical redistribution of ice through the process of ridging, rafting, and shearing. We investigate how well the thickness distribution can be simulated by representing mechanical redistribution as a generalized stacking process. Such processes are naturally described by a well-studied class of models known as Smoluchowski Coagulation Models (SCMs), which describe the dynamics of a population of fixed-mass “particles” which combine in pairs to form a “particle” with the combined mass of the constituent pair at a rate which depends on the mass of the interacting particles. Like observed sea ice thickness distributions, the mass distribution of the populations generated by SCMs has an exponential or quasi-exponential form. We use SCMs to model sea ice, identifying mass-increasing particle combinations with thickness-increasing ice redistribution processes. Our model couples an SCM component with a thermodynamic component and generates qualitatively accurate thickness distributions with a variety of rate kernels. Our results suggest that the exponential tail of the sea ice thickness distribution arises from the nature of the ridging process, rather than specific physical properties of sea ice or the spatial arrangement of floes, and that the relative strengths of the dynamic and thermodynamic processes are key in accurately simulating the rate at which the sea ice thickness tail drops off with thickness.