CAJ | 학술논문

为分析数值模式动力学框架中不同波动的特性及对数值天气预报模式计算稳定性的影响,文章对GRAPES(Global/Regional Assimilation and PrEdiction System)全球非静力大气模式进行了正规模分析.首先,建立了静止大气状态下模式的线性化系统,并在适当的边界条件下将线性化系统分解成具有垂直与水平结构方程的本征值、本征函数耦合问题.然后在等温大气条件下,利用耦合问题的数值结果分析得出:GRAPES非静力模式除了有几乎和对应的静力模式一致的向东、向西传播的重力惯性波及向西传播的Rossby波外,还有一个向东、向西传播的声惯性波;特别是,只有当纵横比较大时,非静力模式对重力惯性波才会有显著影响.
위분석수치모식동역학광가중불동파동적특성급대수치천기예보모식계산은정성적영향,문장대GRAPES(Global/Regional Assimilation and PrEdiction System)전구비정력대기모식진행료정규모분석.수선,건립료정지대기상태하모식적선성화계통,병재괄당적변계조건하장선성화계통분해성구유수직여수평결구방정적본정치、본정함수우합문제.연후재등온대기조건하,이용우합문제적수치결과분석득출:GRAPES비정력모식제료유궤호화대응적정력모식일치적향동、향서전파적중력관성파급향서전파적Rossby파외,환유일개향동、향서전파적성관성파;특별시,지유당종횡비교대시,비정력모식대중력관성파재회유현저영향.
In order to analyze the effects of different atmospheric modes on dynamic procedures and the computational stability in numerical weather prediction,this paper gave a normal mode analysis of the GRAPES (Global/Regional Assimilation and PrEdiction System)global nonhydrostatic atmospheric model. First of all, a system of linearized equations was set up with respect to an atmosphere at rest, and a couple eigenvalue-eigenfunction problem was formulated,which consists of horizontal and vertical structure equations with suitable boundary conditions.By means of numerical analysis for the couple problem under isothermal atmosphere, we arrived at the following conclusion:for the non-hydrostatic model, there is an additional kind of eastward and westward propagating acoustic-inertial oscillation besides eastward and westward propagating gravity-inertial oscillation and westward propagating Rossby oscillation are identical to those in the hydrostatic version of the model. Especially, the non-hydrostatic effect on the gravity-inertial oscillation becomes significant only when the aspect ratio is large.