Exploring a Lower‐Resolution Physics Grid in CAM‐SE‐CSLAM
Exploring a Lower‐Resolution Physics Grid in CAM‐SE‐CSLAM
复制标题
探索 CAM-SE-CSLAM 中的低分辨率物理网格
DOI：
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发表时间：
2019
影响因子：
6.8
通讯作者：
B. Eaton
中科院分区：
文献类型：
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作者：
A. Herrington;P. Lauritzen;K. Reed;S. Goldhaber;B. Eaton
本文描述了在社区大气模型（CAM）中实现粗分辨率物理网格，该网格比动态网格少59列。干动力学用谱元动力核表示，示踪剂输运用保守半拉格朗日有限体积法（CAM‐SE‐CSLAM）计算。提出了在动力学和物理网格之间映射场的算法，同时保持大气模拟的理想数值特性，如质量守恒和混合比形状和线性相关保存。采用低分辨率物理网格的实验结果与物理网格和动态网格重合的传统方法进行了比较。低分辨率物理网格为谱元方法中产生的不同类型节点解的等量采样计算的物理提供了体积平均状态，并有效减轻了地形陡峭地区的网格印记。在aquaplanet配置中，通过一系列动态核心网格分辨率，分析了粗分辨率物理网格对运动分辨率的影响。结果表明，模型的有效分辨率不会因为使用更粗分辨率的物理网格而降低。由于物理计算成本约为传统CAM - SE - CSLAM配置的一半，因此粗糙的物理网格可以节省大量成本，几乎没有任何缺点。
This paper describes the implementation of a coarser‐resolution physics grid into the Community Atmosphere Model (CAM), containing 59 fewer grid columns than the dynamics grid. The dry dynamics is represented by the spectral element dynamical core, and tracer transport is computed using the Conservative Semi‐Lagrangian Finite Volume Method (CAM‐SE‐CSLAM). Algorithms are presented that map fields between the dynamics and physics grids while maintaining numerical properties ideal for atmospheric simulations such as mass conservation and mixing ratio shape and linear‐correlation preservation. The results of experiments using the lower‐resolution physics grid are compared to the conventional method in which the physics and dynamical grids coincide. The lower‐resolution physics grid provides a volume mean state to the physics computed from an equal sampling of the different types of nodal solutions arising in the spectral‐element method and effectively mitigates grid imprinting in regions with steep topography. The impact of the coarser‐resolution physics grid on the resolved scales of motion is analyzed in an aquaplanet configuration, across a range of dynamical core grid resolutions. The results suggest that the effective resolution of the model is not degraded through the use of a coarser‐resolution physics grid. Since the physics makes up about half the computational cost of the conventional CAM‐SE‐CSLAM configuration, the coarser physics grid may allow for significant cost savings with little to no downside.
影响因子：
6.8
作者：
Lauritzen, P. H.;Nair, R. D.;Tribbia, J. J.
通讯作者：
Tribbia, J. J.