“93.5”黑风暴期间中尺度涡旋发生发展的涡源诊断  

Diagnosis of Vorticity Source for the Genesis and Development of Mesoscale Vortex during "93.5" Black Storm

作　　者：张小玲[1] 程麟生[1] 

机构地区：[1]兰州大学大气科学系

出　　处：《兰州大学学报（自然科学版）》1997年第4期123-131,共9页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金

摘　　要：１９９３年５月４日～６日（“９３．５”），在我国西北地区发生了一次极具破坏力的“黑风暴”．为了诊断这次黑风暴中尺度涡旋发生发展的涡源，使用了具有高分辨ＰＢＬ参数化的ＭＭ４对该例控制模拟的输出资料和涡源方程．诊断结果表明：“９３．５”黑风暴的发展与一个中尺度气旋性涡旋的发生和发展直接相关；总涡源的产生、发展及柱状垂直结构的形成和演变与黑风暴中尺度涡旋发展的涡度垂直结构和演变是一致的．该结果揭示，该中尺度涡旋急剧发展的动力机制主要受控于总涡源；对大气总涡源的区分结果指出，与强波扰气流有关的扰动涡源对总涡源的贡献最大；大、中尺度系统间非线性相互作用涡源的贡献次之；与地形强迫有关的时间平均涡源的贡献最小．A 'black storm' with severe destructibility occurred in the Northwest Region of China during 4￣6 May 1993('93.5'). In order to diagnose the vorticity source for the genesis and development of mesoscale vortex during this black storm, the output results of a controlled simulation for this case were used with the help of improved MM4 with high resolution PBL parameterization and vorticity source equation. The diagnosed results indicated that the development of '93.5' black storm was directly related with the formation and development of a mesoscale cyclonic vortex; the formation and development as well as the columnar vertical structure of the total vorticity source were consistent with that of the vorticity of mesoscale vortex during the black storm. These results revealed that the dynamic mechanism of the strong development of this mesoscale vortex was mainly controlled by the total vorticity source. The distinction results of atmospheric total vorticity source in the developing duration showed that the perturbation vorticity source related with strong wave disturbed flow possessed a more important contribution to total vorticity source than the nonlinear interactive vorticity source between largeand mesoscales; and the timeaveraged vorticity source relating to topographic forcing had little contribution to total vorticity source.

关 键 词：黑风暴 中尺度涡旋 涡源诊断 尘暴 

分 类 号：P425.55[天文地球—大气科学及气象学]