Simulation and parametrization of flow over the Earth's orographic features is an important element of any climate or weather model. With increasing resolution, especially in the limited‐area context, the orographic features are not only becoming better resolved but, importantly for numerical stability, the slopes are becoming ever steeper and the currently employed terrain‐following coordinates can cause convergence issues as the curvilinear terms become relatively large. This paper discusses this specific issue and suggests a possible solution based upon an immersed boundary forcing method for representing steep and complex terrain. The method is simple and straightforward to incorporate into any atmospheric model.

中文翻译：

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一个简单的浸入式边界强迫在陡峭而复杂的地形上流动

对地球地形特征上的流动进行模拟和参数化是任何气候或天气模型的重要组成部分。随着分辨率的提高，尤其是在有限区域内，地形特征不仅得到了更好的解决，而且，对于数值稳定性而言，重要的是，坡度变得越来越陡峭，当前采用的地形跟踪坐标可能会导致收敛性问题，例如曲线项变得比较大。本文讨论了这个特定问题，并提出了一种基于浸入边界逼近方法来表示陡峭和复杂地形的可能解决方案。该方法简单易行，可以整合到任何大气模型中。