Comparison of Terrain-Following and Cut-Cell Grids Using a Nonhydrostatic Model
Comparison of Terrain-Following and Cut-Cell Grids Using a Nonhydrostatic Model
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DOI：
10.1175/mwr-d-15-0226.1
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发表时间：
2016-05
影响因子：
3.2
通讯作者：
James Shaw;H. Weller
中科院分区：
文献类型：
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作者：
James Shaw;H. Weller
地形跟随坐标在业务模式中被广泛使用，但切割单元方法已被提出作为一种替代方法，可以更准确地表示陡峭地形上的大气动力学。由于网格的类型通常是在模型实现过程中选择的，因此有必要使用不同的模型来比较不同网格的精度。相比之下，这里的C-网格有限体积模型可以对地形跟随网格和切割单元网格进行类似的比较。一系列标准的二维测试，使用理想化的地形进行：示踪剂平流在规定的水平速度场，测试从静止的初始条件，和orographically引起的重力波描述的非流体静力学。此外，制定了三个新的测试：一个更具挑战性的静止大气的情况下，和两个新的平流测试有一个速度场，到处都是切向的地形以下的坐标表面。这些新的测试提出了一个挑战...
AbstractTerrain-following coordinates are widely used in operational models but the cut-cell method has been proposed as an alternative that can more accurately represent atmospheric dynamics over steep orography. Because the type of grid is usually chosen during model implementation, it becomes necessary to use different models to compare the accuracy of different grids. In contrast, here a C-grid finite-volume model enables a like-for-like comparison of terrain-following and cut-cell grids. A series of standard two-dimensional tests using idealized terrain are performed: tracer advection in a prescribed horizontal velocity field, a test starting from resting initial conditions, and orographically induced gravity waves described by nonhydrostatic dynamics. In addition, three new tests are formulated: a more challenging resting atmosphere case, and two new advection tests having a velocity field that is everywhere tangential to the terrain-following coordinate surfaces. These new tests present a challenge...