【作者】 刘术艳；

【导师】 高炜； 梁信忠；

【作者基本信息】 南京信息工程大学 ， 气象学， 2006， 博士

【摘要】 模拟区域的选择是区域气候模拟研究中的首要问题,计算区域及侧边界处理的最优化(物理和数值上的)对区域气候模式的模拟性能有决定性的作用。物理上合理数值上连续的计算区域为尽可能准确的区域气候模拟奠定了基础,进而为发展合理的物理过程参数化方案提供了前提条件。因此,本文的核心内容为模拟区域的选择问题,分别从影响中国东部季风区降水的天气系统、与大尺度环流场的相关分析及侧边界场资料的代表性三个方面分析区域气候模式模拟区域东西南北四个边界的位置,确定中国东部季风区降水模拟的最佳计算区域,将美国伊利诺伊州立大学水文研究所梁信忠开发的CWRF(Climate extension of WRF—气候版WRF模式)应用于中国东部季风区,研究模拟区域及侧边界条件(驱动场、缓冲区位置、缓冲区处理方案)对中国东部季风区降水模拟的影响。在此基础上,对于选定的最佳模拟区域和侧边界条件,进行嵌套和水平分辨率影响试验,以研究CWRF对中国东部季风区降水模拟宜采用的方案。模式发展的最终目的是要进行相对准确的气候模拟,模拟区域确定以后,模式内部的物理过程至关重要,而对于不同的研究区域和不同的模式,各物理过程的表现并不相同,因此,对CWRF中的物理过程参数化方案进行敏感性试验,为发展适合模拟中国东部季风区降水的物理过程参数化方案提供参考。由于RegCM3为目前国内广为应用的区域气候模式,因此在相同水平和垂直分辨率下,将CWRF的模拟结果与其进行对比研究,结果表明,无论对月平均降水的空间分布型式还是区域平均降水的逐日变化,CWRF对中国东部季风区降水的模拟明显优于RegCM3,同时CWRF较成功地消除了RegCM3模拟时大量出现的数值点风暴(NPS)。更多还原

【Abstract】 The domain of a regional climate model must be carefully selected for its specific application. RCMs are run over limited-area domains and are driven by time-dependent large-scale meteorological fields specified in a buffer area adjacent to the domain’s lateral boundaries. Thus, a successful RCM downscaling from GCM predictions requires an accurate buffer zone treatment that integrates realistic energy and mass fluxes across the RCM lateral boundaries. The most importmant part of the thesis is the choice of model domain. Three factors are considered carefully to decide the best model domain for East China Monsoon Area application. The CWRF—Cliamte extension of WRF—developed by Xin-Zhong Liang is used in the thesis to study the effects of lateral bondary conditions (large scale driver field, buffer zone location, data assimilation technique) as well as model domain on the simulation of East China precipitation. On the basis of the decided model domain and lateral boundary conditions, the experiment of nesting and horizontal grid spacing are conducted to study the scheme of CWRF application in East China. The object of regional climate model is to conduct relative accurte climate simulation, so for the selected model domain, the model internal physical processes are important. While for specific area and regional climate model, the different physical processes have distinct performances. For this consideration, the sensivitiy experiments are conducted to investigate the performances of the physical processes coupled in CWRF. On account of RegCM3 is the most popular regional climate model in China, a comparison between CWRF and RegCM3 simulation results is conducted and the conclusion is that CWRF has apparent superiority than RegCM3.更多还原