We present a historical perspective on ocean mesoscale variability and turbulence, from the physical basis and the first numerical models to recent simulations and forecasts. In the mesoscale range (typically, spatial scales of 100 km and time scales of a month), nonlinearity, and energy cascades were well understood in the 1970s, but the emergence of coherent vortices took place much later. New challenges have arisen with the exploration of the submesoscale regime, where frontal dynamics play a key role and the range of flow instabilities is wider than in the quasi-geostrophic regime. Special focus is placed on the interaction of mesoscale turbulence with the continental slopes. The contrast between the variability on the western and eastern boundaries of an ocean basin is illustrated by numerical simulations of the North Atlantic. On the eastern continental slope, direct forcing of currents by wind fluctuations is more important than it is on the western side of the basin, where forcing by intrinsic mesoscale variability is dominant. Dynamical characteristics of the ocean mesoscale such as these must be taken into account in building forecasting systems. These systems require improved numerical models to represent mesoscale variability with more fidelity. We present our view of the most pressing needs for model development as they relate to the challenges of data assimilation at the mesoscale.

中文翻译：

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中尺度“海洋天气”的建模和预测

从物理基础和第一个数值模型到最近的模拟和预测，我们提出了海洋中尺度变异和湍流的历史视角。在中尺度范围内（通常为 100 公里的空间尺度和一个月的时间尺度），非线性和能量级联在 1970 年代得到了很好的理解，但相干涡旋的出现发生得更晚。随着对亚中尺度区域的探索，新的挑战出现了，其中锋面动力学起着关键作用，流动不稳定性的范围比准地转区域更广。特别关注中尺度湍流与大陆坡的相互作用。北大西洋的数值模拟说明了大洋盆地西部和东部边界变化之间的对比。在东部大陆坡上，风波动对洋流的直接强迫比在盆地西侧更为重要，其中内在中尺度变化的强迫占主导地位。在构建预报系统时，必须考虑到诸如此类的海洋中尺度的动力特性。这些系统需要改进的数值模型来更逼真地表示中尺度变异。我们提出了我们对模型开发最紧迫的需求的看法，因为它们与中尺度数据同化的挑战有关。在构建预报系统时，必须考虑到诸如此类的海洋中尺度的动力特性。这些系统需要改进的数值模型来更逼真地表示中尺度变异。我们提出了我们对模型开发最紧迫的需求的看法，因为它们与中尺度数据同化的挑战有关。在构建预报系统时，必须考虑到诸如此类的海洋中尺度的动力特性。这些系统需要改进的数值模型来更逼真地表示中尺度变异。我们提出了我们对模型开发最紧迫的需求的看法，因为它们与中尺度数据同化的挑战有关。