On the Conditional Frazil Ice Instability in Seawater
On the Conditional Frazil Ice Instability in Seawater
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DOI：
10.1175/jpo-d-14-0159.1
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发表时间：
2015-04
影响因子：
3.5
通讯作者：
James R. Jordan;S. Kimura;P. Holland;A. Jenkins;M. Piggott
中科院分区：
文献类型：
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作者：
James R. Jordan;S. Kimura;P. Holland;A. Jenkins;M. Piggott
冰的存在可能导致海水条件不稳定。水柱中形成的任何碎冰都会降低碎冰-海水混合物的体积密度，导致其上升。由于冰点的压力降低，这会导致更多的冰碴形成，导致包裹加速，等等。本研究使用线性稳定性分析和非静力海洋模式来研究这种不稳定性。作者发现，由过冷水上升引起的冰增长确实能够产生浮力驱动的不稳定性。即使在重力稳定的水柱中，冰机制仍然可以产生对流。不稳定性不存在强密度分层，高热驱动（温水），一个小的初始扰动，高背景混合，或流行的大frazil冰晶。在不稳定的水柱中，不稳定性不一定用分形表示。
AbstractIt has been suggested that the presence of frazil ice can lead to a conditional instability in seawater. Any frazil forming in the water column reduces the bulk density of a parcel of frazil–seawater mixture, causing it to rise. As a result of the pressure decrease in the freezing point, this causes more frazil to form, causing the parcel to accelerate, and so on. This study uses linear stability analysis and a nonhydrostatic ocean model to study this instability. The authors find that frazil ice growth caused by the rising of supercooled water is indeed able to generate a buoyancy-driven instability. Even in a gravitationally stable water column, the frazil ice mechanism can still generate convection. The instability does not operate in the presence of strong density stratification, high thermal driving (warm water), a small initial perturbation, high background mixing, or the prevalence of large frazil ice crystals. In an unstable water column, the instability is not necessarily expressed in fra...