摘要
为了研究垂直变量配置对静力适应过程的影响,本文从描写静力适应过程的方程组出发,分别在将所有变量置于整层上的非跳点N网格;将垂直速度和温度放置在整层,水平速度、气压和密度等变量放置在半层的Charney Phillips跳点网格(CP网格);将水平速度、气压和温度放置在整层,将垂直速度和密度放置在半层的Lorenz跳点网格(L网格);将密度变量放置在整层的Charney Phillips跳点网格(CP_N网格);将密度放置在整层的Lorenz跳点网格(L_N网格)上进行离散,垂直格距分1 km、0.5 km、0.2 km和0.01 km,研究了在这5种网格上产生的频率和垂直群速的相对误差。结果表明:(1)L_N网格和CP网格是完全等效的两种网格。(2)不论垂直格距为多少,CP网格和L网格的误差都是最小,N网格次之,CP_N网格的误差最大。(3)随着垂直格距的减少,在这几种网格上产生的误差都在减小。对于CP网格、L网格和N网格,在水平长波和垂直短波处产生的误差较大。而CP_N网格对水平波长变化不敏感,垂直波长越短,误差越大。(4)当垂直格距为0.01 km时,这几种网格都对水平波长的变化不敏感了,仅对垂直波长敏感。(5)CP网格、L_N网格和L网格在描写静力适应过程和斜压地转适应过程都是误差最小的垂直变量配置方案,因此在非静力完全可压缩深层大气数值预报模式中应优先选择这3种方案。
In order to study the impact of variables vertical distribution on hydrostatic adjustment process,the equations sets describing the hydrostatic adjustment process are discretized on these five grids,the non-staggered N grid on which all variables will be placed on the layer;the Charney Phillips staggered grid(CP grid)on which the vertical velocity and temperature are put on the layer and the horizontal velocity,pressure and density variables are placed on the semi-layer;Lorenz staggered grids(L grid)on which the horizontal velocity,pressure and temperature are put on the layer and the vertical velocity and density are placed on the semi-layer;new Charney Phillips grid on which the density is put on the layer(CP_N grid),new Lorenz grid on which the density is placed on the layer(L_N grid).And the vertical grid spacings are set to 1 km,0.5 km,0.2 km and 0.01 km,respectively.The relative errors of frequency and vertical group velocity generated on these five grids were studied.The results show that(1)L_N grid is equivalent to the CP grid.(2)No matter how many vertical grid spacing is,the errors from CP grid and L grid are the smallest,followed by N grid,and the CP_N grid shows the maximum errors.(3)The errors generated on these grids are reduced with the decrease of the vertical grid spacing.Large errors are produced at the vertical short wave and horizontal long wave for the CP,L and N grids.Meanwhile,for the CP_N grid,the error is insensitive to the change of the horizontal wavelength;however the shorter the vertical wavelength is,the greater the errors become.(4)These grids are only sensitive to the changes of vertical wavelength but insensitive to the changes of the horizontal wavelength when the vertical grid spacing is 0.01 km.(5)The CP,L_N and L grids are suitable to describe both of the hydrostatic adjustment process and baroclinic geostrophic adjustment process due to their minimal errors.So they should be preferable in the numerical prediction model of non-hydrostatic full-compressible deep atmosphere.
作者
郭海龙
刘宇迪
眭敏
余江林
GUO Hailong;LIU Yudi;SUI Min;YU Jianglin(Institute of Meteorology and Oceanography,National University of Defense Technology,Nanjing 211101,China;The Satellite Launch Center of Taiyuan,Taiyuan 036301,China)
出处
《气象科学》
北大核心
2019年第4期446-456,共11页
Journal of the Meteorological Sciences
基金
国家自然科学基金资助项目(41875060)
关键词
静力适应过程
斜压地转适应过程
声重力波
垂直变量配置
hydrostatic adjustment process
baroclinic geostrophic adjustment process
acoustic-gravity wave
variables vertical distribution
