两种积云对流参数化方案对1998年区域气候季节变化模拟的影响研究  

Impacts of Cumulus Parameterization Scheme on the Seasonal Variation Simulation of Regional Climate in 1998

作　　者：胡轶佳[1] 钟中[1] 闵锦忠[2] 

机构地区：[1]解放军理工大学气象学院,南京211101 [2]江苏省气象灾害重点实验室,南京210044

出　　处：《大气科学》2008年第1期90-100,共11页Chinese Journal of Atmospheric Sciences

基　　金：国家自然科学基金资助项目40333026、40675065;江苏省气象灾害重点实验室项目KJS0605

摘　　要：利用区域气候模式RegCM3,选择Kuo-Anthes积云对流参数化方案和基于FC80假设的Grell积云对流参数化方案,对1998年东亚气候分别进行年尺度模拟,模拟结果对比分析表明:在春、夏季转换时期,两者模拟的降水形势差别较大,对江淮、中南和华南地区的夏季降水量模拟差别最为明显。对流层上层模式变量和模式大气质量对积云对流参数化方案的选择不敏感,而对流层中、下层模式变量对积云对流参数化方案比较敏感。不同积云对流参数化方案对8天时间尺度的天气系统模拟差别比较大。在积云对流比较活跃的夏季,不同参数化方案会导致模式大气出现不同的系统性偏差。由于模式在陡峭地形处动力过程计算方案存在缺陷,在高原与盆地的交界处,模式误差会产生明显的突变。Cumulus convection is one of the primary physical processes influencing the transportation and distribu tion of energy and mass in the atmosphere, and it is also the most difficult process represented in numerical models. Due to the different strategies employed in different cumulus parameterization schemes （CPS）, the obtained simula tion results are considerably sensitive to the adopted CPS. In this paper, using the regional climate model RegCM3, an annual scale simulation is performed over East Asia for 1998 with the Kuo-Anthes CPS （EKuo） and the Grell CPS based on the Fritsch-Chappell assumption （EGrell）. The impact of the employed CPS on seasonal variation simulations is analyzed. The comparative analysis between the precipitations simulated with EKuo and EGrell and obtained trom CRU shows that the temporal and spatial features of precipitation distribution can be reproduced well using the Kuo-Anthes or Grell schemes. However, the sensitivity of the precipitation simulation to the employed CPS is more distinct in spring and summer than in autumn and winter, and the most significant distinction appears in April and May. In autumn and winter, when cumulus convection is not active, essentially similar precipitation scenarios are obtained; this is also true over Southwest and North China for all seasons. However, the precipitation scenarios are different over the Changjiang River- Huaihe River basin, South Central China, and South China in summer, and the precipitation simulation over South China is most sensitive to the employed CPS. The temporal variation characteristics of the regionally averaged biases of the daily meteorological variables simulated with EKuo and EGrell show that the variables in the upper troposphere and the surface pressure are independent of the employed CPS basically, whereas the variables in the lower troposphere are sensitive to the used CPS. However, there is no essential difference between the simulated regional atmospheric circulations. By applying the db5 wavelet d

关 键 词：区域气候模式 积云对流参数化方案 小波分解 系统性偏差 

分 类 号：P463[天文地球—大气科学及气象学]