New approach to incorporating the impacts of non-hydrostatic perturbations in atmospheric models  

作　　者：ZHANG Fa-Bo WANG Bin LI Li-Juan 

机构地区：[1]State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG), Institute of Atmospheric Physics(IAP), Chinese Academy of Sciences (CAS) [2]College of Earth Science, University of Chinese Academy of Sciences (UCAS) [3]Ministry of Education Key Laboratory for Earth System Modeling, Center of Earth System Science (CESS), Tsinghua University

出　　处：《Atmospheric and Oceanic Science Letters》2017年第5期379-384,共6页大气和海洋科学快报（英文版）

基　　金：supported by the National Key Research and Development Program[grant number 2016YFB0200805];the National Natural Science Foundation of China[grant number 41622503]

摘　　要：How to properly consider the impacts of non-hydrostatic perturbations is one of the challenging issues in developing non-hydrostatic dynamics solvers（NHDSs） for high-resolution atmospheric models. To overcome the drawbacks of current approaches to tackling this issue, this study analyzed the differences between hydrostatic dynamics solvers（HDSs） and their non-hydrostatic counterparts.The analysis then motivated a flexible approach to adjusting existing hydrostatic atmospheric models,especially those adopted in climate simulations for the impacts of non-hydrostatic perturbations.In this approach, the impacts of non-hydrostatic perturbations, reflecting the differences between HDSs and NHDSs, were encapsulated into a single term in the vertical momentum equation for the atmosphere. At each time step, this term was estimated by a separate sub-model, and then it was used to adjust the dynamics of the atmosphere. The adjustment was optional, and could be turned on and off flexibly by utilizing different initial conditions. The approach was illustrated using the Weather Research and Forecasting（WRF） model as an example, and was preliminarily validated by running the 3D baroclinic-wave test case in the model. Results showed that the modified dynamics solver produced simulation results that were very close to those given by the standard NHDS in the WRF model, implying that the approach was basically effective in capturing the non-hydrostatic features of the atmosphere.通过对静力和非静力模式动力框架进行对比分析,研究发现:非静力扰动主要影响大气的垂直运动,对于水平运动的影响相对而言较小,且其影响可通过一个控制其打开和关闭状态的开关性变量来予以表示。基于上述发现,提出了一套新的非静力扰动整合方案。该方案将复杂耗时的偏微分方程数值求解问题转化为基于历史数据的局部函数建模问题,且能够比较方便地应用于一般的静力模式动力框架当中,大大降低了非静力大气环流模式的研发难度和工作量。

关 键 词：HYDROSTATIC NON-HYDROSTATIC dynamics solver WRF 

分 类 号：P43[天文地球—大气科学及气象学]