WARMS 2.0中边界层参数化方案对一次台风外围降水模拟预报的影响

Impact of Different Boundary Layer Parameterization Schemes on the Numerical Smiulation for a Typhoon Rain Event in WARMS 2.0

为分析高分辨率数值预报模式下不同边界层参数化方案对降水过程的模拟结果及边界层参数化方案中局地混合与非局地混合作用对模拟结果产生的不同影响,利用华东区域中尺度数值预报系统WARMS 2.0,使用不同边界层参数化方案对一次台风外围强降水过程进行模拟,得出主要结论:非局地混合YSU方案对强降水中心位置的模拟能力最好,且对台风雨带结构的模拟更准确明显,但模拟降水的强度偏大;局地混合MYJ方案容易产生小量级虚假降水;未使用边界层参数化方案时的模拟能力最弱,降水范围小、强度弱,与实况相比差异较大。在对强降水过程进行模拟时,非局地混合方案在垂直方向上的湍流作用更强,模拟的强降水范围和强度均大于局地混合方案。由降水检验来看,非局地混合YSU方案的预报技巧优于其他方案,易模拟出较大量级降水,而局地混合MYJ方案更容易预报出较小量级的降水。

In order to analyze the simulation results of precipitation and the effects of local and nonlocal mixing of planetary boundary layer parameterization schemes in high resolution numerical forecast model,WRF ADAS Real-time Modeling System 2.0 （WARMS 2.0） is used.And a case of heavy rainfall process near a typhoon were numerically simulated using different boundary layer parameterization schemes.The main conclusions are as follows：the nonlocal mixing YSU scheme has the best simulation ability about the location of the strong precipitation center and the structure of the typhoon rain belt,but the intensity is stronger;the local mixing YSU scheme is tend to produce a small amount of nonexistent precipitation;without boundary layer parameterization schemes,the simulation capacity of this modle is weakest,and the precipitation range is least,moreover,the intensity is weakest,which has a lot of difference with the observated rainfall.The turbulence in the vertical direction is stronger,and the range and intensity of the strong precipitation are larger in the nonlocal mixing scheme.Based on the precipitation tests,the nonlocal mixing YSU scheme is superior to other schemes for the simulation,while the local mixing MYJ scheme is easier to predict the smaller magnitude precipitation.