A Global Eta Model on Quasi - uniform Grids
نویسنده
چکیده
Application of the quasi-uniform grids in global models of the atmosphere is an attempt to increase the computational efficiency by a more cost effective exploitation of the computing infrastructure. This paper describes the development of a global version of NCEP’s regional, step-coordinate, Eta model on two quasi-uniform girds: cubic and octagonal. The governing equations are expressed in a general curvilinear form, so that the cubic and the octagonal version of the model share the same code in spite of different mapping of the computational domain. The dynamical core of the derived global Eta model is successfully tested in the benchmark test of Held and Suarez. The model with the step-wise formulation of the terrain and full physics is integrated in a series of tests with real data, and the results are compared both with the analysis and the results of the regional Eta model.
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