标题： 海洋中尺度涡旋的大涡模拟 显示英文标题

标题： Large eddy simulation of ocean mesoscale eddies

摘要： 中尺度涡旋产生横向（2D）通量，由于水平分辨率不足，在允许涡旋存在的（1/4度）全球海洋模型中需要对其进行参数化。 在这里，我们系统地应用来自三维 LES（大涡模拟）领域的方法，利用显式滤波方法和动态过程来参数化由中尺度涡旋产生的横向涡度通量。 开发的亚滤波闭合方案被应用于 GFDL MOM6 海洋模型，并在理想化的双涡旋配置中进行了先验和后验评估。 对于足够解析的网格，LES 模拟会收敛到过滤后的高分辨率数据。 然而，当滤波尺度接近能量包含尺度时，所提出的闭合方案存在局限性：先验性能下降，后验实验无法收敛到过滤后的高分辨率数据。 尽管如此，在所有考虑的分辨率（1/2-1/8 度）下，所提出的闭合方案在后验模拟中对平均流的预测是准确的。 最后，我们提出使用 Bardina 模型对厚度通量进行参数化，这进一步提高了最粗分辨率（1/2-1/3 度）下的模拟效果。 显示英文摘要

摘要： Mesoscale eddies produce lateral (2D) fluxes that need to be parameterized in eddy-permitting (1/4-degree) global ocean models due to insufficient horizontal resolution. Here, we systematically apply methods from the 3D LES community to parameterize lateral vorticity fluxes produced by mesoscale eddies leveraging an explicit filtering approach together with a dynamic procedure. The developed subfilter closure is implemented into the GFDL MOM6 ocean model and is evaluated in an idealized double-gyre configuration, both a-priori and a-posteriori. For sufficiently resolved grids, the LES simulations converge to the filtered high-resolution data. However, limitations in the proposed closure are observed when the filter scale approaches the energy-containing scales: the a-priori performance drops and a-posteriori experiments fail to converge to the filtered high-resolution data. Nevertheless, the proposed closure is accurate in predicting the mean flow in a-posteriori simulations at all resolutions considered (1/2-1/8 degrees). Finally, we propose parameterizing the thickness fluxes using a Bardina model which further improves simulations at the coarsest resolutions (1/2-1/3 degrees).