Implementation of the Semi-Lagrangian Advection Scheme on a Quasi-Uniform Overset Grid on a Sphere

• Published in: Advances in atmospheric sciences Vol. 23; no. 5; pp. 792 - 801
• Main Author: 李兴良 陈德辉 彭新东 肖锋 陈雄山
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Nature B.V 01.10.2006; Nanjing University of Information Science and Technology,Nanjing,210044%State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081%Earth Simulator Center, Japan Agency for Marine-earth Science and Technology, Yokohama, Japan%State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081; Tokyo Institute of Technology, Yokohama, Japan%Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029
• Subjects: Advection; Mathematical analysis; Studies; 准确度; 大气数值模型; 拉格朗日量; 球面几何学; semi-Lagrangian scheme; Yin-Yang grid; spherical geometry
• ISSN: 0256-1530; 1861-9533
• DOI: 10.1007/s00376-006-0792-9

The semi-Lagrangian advection scheme is implemented on a new quasi-uniform overset （Yin-Yang） grid on the sphere. The Yin-Yang grid is a newly developed grid system in spherical geometry with two perpendicularly-oriented latitude-longitude grid components （called Yin and Yang respectively） that overlapp each other, and this effectively avoids the coordinate singularity and the grid convergence near the poles. In this overset grid, the way of transferring data between the Yin and Yang components is the key to maintaining the accuracy and robustness in numerical solutions. A numerical interpolation for boundary data exchange, which maintains the accuracy of the original advection scheme and is computationally efficient, is given in this paper. A standard test of the solid-body advection proposed by Williamson is carried out on the Yin-Yang grid. Numerical results show that the quasi-uniform Yin-Yang grid can get around the problems near the poles, and the numerical accuracy in the original semi-Lagrangian scheme is effectively maintained in the Yin-Yang grid.