山东半岛一次强暴雨的分析和数值模拟  

Analysis and Numerical Simulation of a Severe Heavy Rainfall in Shandong Peninsula

作　　者：周淑玲[1,2] 吴增茂[2] 闫丽凤 

机构地区：[1]山东省威海市气象局,山东威海264200 [2]中国海洋大学海洋环境学院,山东青岛266003 [3]山东省烟台市气象局,山东烟台264003

出　　处：《高原气象》2008年第5期1149-1160,共12页Plateau Meteorology

基　　金：国家自然科学基金项目(40675068)资助

摘　　要：利用T213资料、常规观测资料和多普勒雷达资料,对2004年8月5日发生在山东半岛东部的一次大暴雨过程进行了数值模拟和分析,在模拟结果比较成功的基础上,利用细网格模拟资料重点分析了高、低空急流和850 hPa低压与暴雨的关系,以及山东半岛地形的动力作用。结果表明:暴雨强回波从南向北传播时强度逐渐增强,反映了中尺度对流系统的结构和发展;对流云团首先在低空急流中心左前方生成,与副热带高压边缘的西南暖湿气流有关,中尺度高空急流是伴随对流由强高空出流而形成,高、低空急流的耦合作用有利于强对流天气的维持和发展;在副热带高压西侧边界层激发出一个中β尺度低压,该低压形成后与暴雨区相伴移动,且移动路径与山东半岛东部地形分布有关,山东半岛地形对西南暖湿气流阻挡和绕流的动力作用是导致威海附近强暴雨的原因之一。A diagnosis and simulation study have been conducted to reveal the feature of the heavy rainstorm in the east of Shandong Peninsula on 5 August 2004 by using T213 data and routine observation data. The evolutionary process and development mechanism of the heavy rainstorm process are analyzed with emphasis on the orogrphic effect of Shandong Peninsula on the development of the upper and low-level jets as well as the development of vortex in the boundary layer. The simulated results indicated that the moving echo of radar from south to north along with the rainstorm showed the structure and development of the mesocal systems. The low-level jet（LLJ） and upper-level jet（ULJ） intensified with the development of convective system while they reached the Shandong Peninsula. The center of LLJ which lay to the south of the mesocal systems was caused by the southwest ward warm air current on the western side of the western Pacific ocean subtropical high. The upper-level mesoscal jet formed by the upper level outflow of convection occurred during the evolution of convection. The interaction of LLJ and mesoscale ULJ could maintain and accelerate the development of convective system. It is also shown that the meso-β-scale vortex was produced in the boundary on the western side of the western Pacific ocean subtropical high. After its formation, this meso-β-scale vortex moved northwest ward accompanied with heavy rainstorm and the moving route of this meso-β-scale vortex is related to the distribution of the topography in Shandong Peninsula. The southwest warm air current was blocked by Shandong Peninsula and forced to move around it, which was one of the reasons the heavy rainstorm occurring in Weihai, Shandong Province.

关 键 词：山东半岛 暴雨 数值模拟 地形作用 高 低空急流 

分 类 号：P458.121.1[天文地球—大气科学及气象学]