Effect of Planetary Rotation on Oceanic Surface Boundary Layer Turbulence
Effect of Planetary Rotation on Oceanic Surface Boundary Layer Turbulence
复制标题
行星自转对海洋表面边界层湍流的影响
DOI：
10.1175/jpo-d-17-0150.1
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发表时间：
2018
影响因子：
3.5
通讯作者：
Q. Chen
中科院分区：
文献类型：
--
作者：
Jinliang Liu;Jun‐Hong Liang;J. McWilliams;P. Sullivan;Yalin Fan;Q. Chen
配置了一个大涡模拟(LES)模式来研究地球自转的水平(向北)分量对上层海洋湍流的影响。重点是在表面重力波存在和被表层下稳定的层结覆盖时，影响随纬度/半球变化的情况。当包含时，平均气流、湍流和垂直混合取决于风向。热带雨量的大小和影响在热带地区最大，并随着纬度的增加而减小。不同纬度和不同半球的湍流对风向的变化是不同的。当受到稳定层结的限制时，湍流强度对风向的变异性减小，但卷流率随风向变化。在波动驱动的朗缪尔湍流中，平均流对风向的变化较小，但湍流对风向的变化很明显。当有随风涌浪时，平均海流对风向的变异性进一步减小。与Ekman湍流相比，当有较强的逆风涌浪，使得总的波浪强迫与风相反时，平均流对风向的变异性减小，而湍流对风向的变异性增强。涡粘性廓线，包括它的形状和大小，对层状风生和波生朗缪尔湍流都表现出很强的风向依赖性。我们的研究表明，风向是上层海洋混合的一个重要参数，尽管现有的海洋模式忽略了它。
A large-eddy simulation (LES) model is configured to investigate the effect of the horizontal (northward) component of Earth’s rotation on upper-ocean turbulence. The focus is on the variability of the effect with latitude/hemisphere in the presence of surface gravity waves and when capped by a stable stratification beneath the surface layer. When is included, the mean flow, turbulence, and vertical mixing depend on the wind direction. The value and effect of are the largest in the tropics and decrease with increasing latitudes. The variability in turbulent flows to wind direction is different at different latitudes and in opposite hemispheres. When limited by stable stratification, the variability in turbulence intensity to wind direction reduces, but the entrainment rate changes with wind direction. In wave-driven Langmuir turbulence, the variability in mean current to wind direction is reduced, but the variability of turbulence to wind direction is evident. When there is wind-following swell, the variability in the mean current to wind direction is further reduced. When there is strong wind-opposing swell so that the total wave forcing is opposite to the wind, the variability in the mean current to wind direction is reduced, but the variability of turbulence to wind direction is enhanced, compared to in Ekman turbulence. The profiles of eddy viscosity, including its shape and its value, show a strong wind direction dependence for both stratified wind-driven and wave-driven Langmuir turbulence. Our study demonstrates that wind direction is an important parameter to upper-ocean mixing, though it is overlooked in existing ocean models.
影响因子：
3.5
作者：
Grant, Alan L. M.;Belcher, Stephen E.
通讯作者：
Belcher, Stephen E.
影响因子：
5.2
作者：
Belcher, Stephen E.;Grant, Alan L. M.;Polton, Jeff A.
通讯作者：
Polton, Jeff A.