一个谱元大气临近空间分辨模式

发展了一个可分辨大气临近空间且采用谱元数值计算技术的大气数值模式SEMANS(Spectral Element Model with Atmospheric Near Space resolved),并对模式模拟能力进行检验.数值模式采用立方体球面投影坐标,每个投影面分解为81个局地元,在元内利用8次Gauss-Lobatto-Legendre插值多项式对变量进行谱离散;模式大气在铅直方向分为66层,大气顶气压取为4.5×10^-6 hPa.进行了10年积分试验,利用ECMWF(European Center for Medium-Range Weather Forecasts)ERA-Interim再分析数据集和COSPAR(Committee on Space Research)国际参考大气1986对SEMANS模拟结果进行初步检验.结果表明,模式模拟出30 hPa等压面上北半球纬向2波特征及南半球纬向1波特征;模式能模拟出100 hPa和0.001 hPa等压面附近的低温区及1 hPa等压面附近和0.0001 hPa等压面高度之上的高温区;模式还模拟出0.001 hPa等压面高度以下1月及7月纬向平均纬向风随高度分布的主要特征.

A Spectral Element Model with Atmospheric Near Space Resolved (SEMANS)

A numerical model,which solves equations with spectral element method and resolves atmospheric near space,is developed.Model validations are performed.The spectral element model with atmospheric near space resolved (SEMANS) is integrated for 10 years under configuration of 81 local elements in each projected face of cubed sphere with spectral approximation of 8th degree Gauss-Lobatto-Legendre interpolation polynomial and 66 vertical layers with top layer pressure 4.5×10^-6 hPa.Through verification against ERA-Interim reanalysis dataset from ECMWF (European Center for Medium-Range Weather Forecasts) and COSPAR (Committee on Space Research) international reference atmosphere 1986,it is found that SEMANS reproduces features of 2 wave-lengths pattern along zonal circle in the northern hemisphere and 1 wave-length pattern along zonal circle in the southern hemisphere at 30hPa;SEMANS reproduces zones of low temperature at about 100 hPa,0.001 hPa and high temperature at about 1 hPa,above 0.0001 hPa;SEMANS also reproduces main features of zonal mean zonal wind in January and July below 0.001 hPa level.