Mean Currents Driven by Topographic Drag over the Continental Shelf and Slope
Mean Currents Driven by Topographic Drag over the Continental Shelf and Slope
复制标题
大陆架和斜坡上地形阻力驱动的平均洋流
DOI：
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发表时间：
1986
期刊：
影响因子：
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通讯作者：
K. Brink
中科院分区：
文献类型：
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作者：
D. Haidvogel;K. Brink
摘要对不规则陆架地形上的风驱动流进行了一系列数值模拟。该模式是正压的，非线性的，并迫使由周期性的，空间均匀的沿陆架风应力。这项研究的目的是确定地形阻力，已知是不对称的正压气流在货架上，可以产生大量的时间平均沿岸电流的存在下，波动的零平均风应力。在实际参数下，沿自由传播的陆架波方向流动时，平均最大沿岸流为0.05至7.0 cm s-1。剩余流强度是风应力周期和底鼓波长的强函数：较大的强迫周期和较短的底鼓波长增强时间平均环流。粒子路径通常被观察到是混沌的，与欧拉速度场的近似循环行为相反。然而，越岸颗粒弥散与平均沿海岸线分布有很好的相关性。
Abstract A sequence of numerical simulations is described of wind-driven flow over irregular continental shelf topography. The model is barotropic, nonlinear, and forced by a periodic, spatially uniform alongshelf wind stress. The objective of the study is to determine whether topographic drag, known to be asymmetric for barotropic flow over the shelf, can generate substantial time-averaged alongshore currents in the presence of a fluctuating zero-mean wind stress. With realistic parameters, mean maximum alongshore currents of 0.05 to 7.0 cm s−1 are realized with flow in the direction of freely propagating shelf waves. The residual current strength is a strong function of wind stress period and bottom bump wavelength: larger forcing periods and shorter bump wavelengths enhance the time-mean circulation. Particle paths are generally observed to be chaotic, in contrast to the nearly cyclic behavior of the Eulerian velocity field. However, cross-shore particle dispersion is well correlated with the mean alon...