Comparison and Analysis of Two Different Calculation Schemes of SLEVE-Hybrid Coordinate in the GRAPES_MESO Model  

作　　者：LI Chao LI Xing-liang HU Jiang-lin 李超;李兴良;胡江林(National Meteorological Center,CMA,Beijing 100081 China)

机构地区：[1]National Meteorological Center,CMA,Beijing 100081 China

出　　处：《Journal of Tropical Meteorology》2021年第2期87-93,共7页热带气象学报（英文版）

基　　金：National Key R&D Program of China(2017YFC1502001, 2017YFC1501901)

摘　　要：The calculation scheme of the smoothed-level and hybrid(SLEVE-hybrid for short)coordinates in numerical forecasting model is not limited in number.It is divided into the semi-analytical scheme and the finite differential scheme in terms of the various differential methods of the coordinate deformation variables.Having compared the dynamic equation and the long-time batch simulation results of the two schemes,the present study draws the following conclusions.The first-order finite difference accuracy of the coordinate deformation variables in the finite differential scheme is theoretically lower than that in the semi-analytical scheme.The larger the vertical gradient of the layer thickness is,the larger the relative errors of the finite differential scheme are.The long-time batch simulation test in the GRAPES model dynamic core demonstrates that the bias of the temperature and the geopotential height in the semianalytical scheme is smaller under the default layering,while the simulation difference of the two schemes is greatly reduced when the layering is more uniform.

关 键 词：GRAPES model SLEVE-hybrid coordinate dynamic core numerical modelling 

分 类 号：P456.7[天文地球—大气科学及气象学]