Hydraulic control of continental shelf waves
Hydraulic control of continental shelf waves
复制标题
大陆架波浪的水力控制
DOI：
10.1017/jfm.2021.250
复制
发表时间：
2021
影响因子：
3.7
通讯作者：
Jamshidi S
中科院分区：
文献类型：
--
作者：
Jamshidi S
本文利用一个具有分段常位涡的无粘正压准地转模式研究了陆架波的水力控制。一个沿海加强的地转流产生的地形Rossby波，这可能成为关键的在当地的货架宽度减少时，背景电流反对Rossby波传播。也就是说，shelfbreak扰动永久修改流场在任意大的距离和流动过渡从亚临界到超临界，因为它穿过扰动。严格控制的水流还导致大陆架和深海之间大量的水交换。我们推导出临界控制发生的弗劳德数和无量纲的扰动幅度方面的边界，并分析控制和远场流之间可能的过渡。当一阶色散项被包括在模型中，过渡被解决的色散激波，它仍然附着在强制区域时，弗劳德数接近临界流的边界。轮廓动力学模拟表明，色散长波模型捕获的定量行为的充分准地转系统缓慢变化的货架，并复制的定性行为，即使当长波参数是为了一。
This paper studies the hydraulic control of continental shelf waves using an inviscid barotropic quasi-geostrophic model with piecewise-constant potential vorticity, in which the shelf is represented by a flat step of variable width. A coastal-intensified geostrophic current generates topographic Rossby waves, which can become critical at a local decrease in shelf width when the background current opposes Rossby wave propagation. That is, the shelfbreak perturbation permanently modifies the flow field over arbitrarily large distances and the flow transitions from subcritical to supercritical as it crosses the perturbation. Critically controlled flows also lead to the exchange of significant volumes of water between the shelf and the deep ocean. We derive the boundaries for which critical control occurs in terms of a Froude number and the dimensionless magnitude of the perturbation, and analyse the possible transitions between controlled and far-field flow. When first-order dispersive terms are included in the model, transitions are resolved by dispersive shock waves, which remain attached to the forcing region when the Froude number is close to the boundary for critical flow. Contour dynamic simulations show that the dispersive long-wave model captures the quantitative behaviour of the full quasi-geostrophic system for slowly varying shelves, and replicates the qualitative behaviour even when the long-wave parameter is order one.
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DOI：
--
发表时间：
1986
期刊：
影响因子：
--
作者：
L. Pratt;M. Stern
通讯作者：
M. Stern
影响因子：
3.7
作者：
E. Johnson;O. Southwick;N. R. McDonald
通讯作者：
E. Johnson;O. Southwick;N. R. McDonald
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影响因子：
3.5
作者：
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通讯作者：
S. Lentz
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DOI：
--
发表时间：
2006
期刊：
影响因子：
--
作者：
E. Johnson;N. R. McDonald
通讯作者：
N. R. McDonald
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影响因子：
3.7
作者：
G. El;R. Grimshaw;N. F. Smyth
通讯作者：
N. F. Smyth