【作者】 陈玉林；

【导师】 周军；

【作者基本信息】 南京信息工程大学 ， 气象学， 2005， 硕士

【摘要】 本文采用地面高空常规资料,对2004年8月8～14日间0414号台风“云娜”登陆浙江时所产生的一次暴雨过程的影响系统及其可能机制进行了初步的诊断分析,发现我国东北地区浅槽两侧的副热带高压即西边的大陆高压、东边日本海副热带高压是影响本次台风暴雨的主要大尺度环流系统;深厚的对流系统是台风在大陆上产生降水的直接原因;螺旋带的密实结构是台风将产生强降水的重要指标;有利的地形条件对降水起了重要的增幅作用;中、低纬度系统相互作用是暴雨和强对流天气发生发展的重要触发机制。 利用双向嵌套中尺度非静力数值预报模式MM5V36,对2004年8月12日登陆我国浙江温州的0014号(云娜)台风所引发的暴雨过程进行了24小时数值模拟,结果表明:该模式能较好地模拟这次过程,模拟的降水落区和降水强度与实况比较一致,特别是对台风暴雨中心的位置和降水量的预报与实况十分吻合;对850hPa台风流场的模拟预报分析表明,台风的中心位置和移动路径与实况的极为接近。地形敏感性试验证明:(1) 地形可以增加台风中心及其附近的降水量;(2) 地形及地形增高可以使雨量分布更加不均匀;(3) 除了台风外围的西侧,特别是东海海面上的降水增幅与台风中心及附近的降水变化呈反位相变化关系;(4) 台风降水受地形影响呈现出类重力波列式的正负相间的变化分布。更多还原

【Abstract】 By using the conventional observational datasets, the causes of the typhoon rainstorm process occurred on during 8-14 Aug 2004 in Zhejiang Province were studied. The primary diagnostic analyses show that the Continental High/ subtropical high in Japan Sea on the west/east of the shallow slot though in the northeast China is the mainly large-scale circulation systems. It is found that the deep convective system was the direct cause of the rainstorm; the dense structure of helical ribbon was the impact factor whether the typhoon can cause the severe rainstorm; the favorable terrain may enhance precipitation; the interaction between mid and low latitude circulations is the great trigger mechanism of the typhoon rainstorm and sever convective weather.Based on the two-way nested non-hydrostatic mesoscale numerical model (MM5V36), a series of sensitive experiments are carried out to simulate 24-hour precipitation caused by the landfall typhoon "RANANIM" on 12 August 2004. The results show that the simulated rainfall area and the precipitation intensity are excellent agreement with the observations, especially for the position of the typhoon rainfall center and the precipitation rate. The analysis of the simulated 850hPa flow field shows the center position and moving track of typhoon are also very closely with observations. Terrain sensitive experiments proved that: (1) the increase of rainfall near the center of the typhoon has a close relation with the terrain; (2) terrain tendency and height can result in more uniformity of the precipitation distribution; (3) except for the precipitation on the west of periphery of the typhoon, the precipitation enhancement extent appears counter of phase relationship with that of the typhoon center or near the typhoon, especially on the region of the East Sea; (4)The distribution of typhoon precipitation presents the positive ad negative change as the gravity wave column wise under the influence of terrain.更多还原