云微物理过程对台风数值模拟的影响  

The Impact of Cloud Microphysical Processes on Typhoon Numerical Simulation

作　　者：常婉婷 高文华[1] 端义宏[1] 邓琳[1] Chang Wanting;Gao Wenhua;Duan Yihong;Deng Lin(State Key Laboratory of Severe Weather,Chinese Academy of Meteorological Sciences,Beijing 100081)

机构地区：[1]中国气象科学研究院灾害天气国家重点实验室

出　　处：《应用气象学报》2019年第4期443-455,共13页Journal of Applied Meteorological Science

基　　金：国家重点基础研究发展计划(2015CB452805)

摘　　要：将中国气象科学研究院(CAMS)混合双参数云微物理方案用于中尺度天气模式WRF,开展了对2013年超强台风天兔(1319)的模拟,通过与台风最佳路径、强度及热带降雨测量卫星(TRMM)资料对比,分析CAMS云微物理方案在模拟台风中的适用性及云微物理过程对模拟台风天兔的影响机制。设计了3组敏感性试验:修改雪粒子质量和落速系数(EXP1),采用海洋性云滴参数(EXP2),同时修改雪粒子质量和落速系数并采用海洋性云滴参数(EXP3)。结果表明:EXP1和EXP3由于霰碰并雪速率的增加及减小的雪下落通量,导致雪含量显著降低,同时也减少了整体冰相物的含量;EXP2和EXP3模拟的台风眼区对流有效位能快速减小,再现了前期台风的快速增强过程,路径偏差也最小;各试验模拟的小时降水率总体偏强,EXP3的降水空间分布与实况更接近,明显降低雪粒子含量,并一定程度上改善模拟的台风路径、强度及降水分布等。该结果不但可为改进适用于台风的云微物理参数化方案提供思路,也可加深云微物理过程对台风影响的认识。Previous studies show that the cloud microphysical process affects the precipitation, as well as the intensity, internal structure and evolution process of tropical cyclones. Thus, the rational description of the cloud microphysical process is crucial. And the correctness of the cloud microphysical process is the basis of the high-resolution model in simulating precipitation and fine-scale structure of typhoon. The two-moment bulk microphysics scheme developed by Chinese Academy of Meteorological Sciences (CAMS) is a mixed phase two-moment cloud microphysics scheme, which can simulate cloud microphysics processes in different weather systems. However, whether it can be applied to the simulation of tropical cyclones is still uncertain. Four numerical experiments of typhoon Usagi (2013) are conducted by using the Weather Research and Forecasting (WRF) model with Chinese Academy of Meteorological Sciences two-moment microphysics scheme (CAMS). The simulated track, intensity, cloud microphysics and rainfall are compared with the observed typhoon best track dataset and satellite observations to evaluate performances of CAMS microphysics scheme and investigate the possible impacts of cloud microphysical processes on Typhoon Usagi. To overcome the overestimation of snow content in control experiment (CTRL), three sensitivity experiments are designed:Modifying coefficients of snow particle mass and falling velocity (EXP1), using the typical oceanic cloud droplet parameter (EXP2), and including changes in both EXP1 and EXP2 (EXP3). It shows that the snow content is significantly reduced in the EXP1 and EXP3 due to the increased rate of accretion of snow by graupel and the slightly reduced snow mass flux, and the content of whole ice-phase hydrometeors are also reduced. The rapid intensification process in the early stage of typhoon Usagi is well captured in EXP2 and EXP3 owing to the better simulated CAPE in eye region, and their intensity and track are also better than those in CTRL. Although the hourly precipitation rat

关 键 词：CAMS云微物理方案 台风 微物理过程 数值模拟 

分 类 号：P461[天文地球—大气科学及气象学]