【作者】 边清河；

【导师】 丁治英；

【作者基本信息】 南京气象学院 ， 气象学， 2003， 硕士

【摘要】 本文对1949～2000年发生在华北地区的台风暴雨进行统计研究，得出：台风暴雨的年代际差异十分突出。六十年代最多，八十年代最少。52年中，由台风引起的暴雨共51次，平均每年1次，且主要出现在夏季(尤以7、8月最多)；台风登陆地点以江苏、浙江、福建为主；台风与西风带系统相互作用型、亚相互作用型、非相互作用型，分别占58.8％、23.5％、17.6％。 为了弄清台风与中纬度系统的相互作用，对1996年9608号台风进行了数值模拟和诊断分析。结果表明：低层副热带高压和台风东部的等高线的结合使低空急流和水汽输送加强。东北部的冷空气向西南运动生成和加强了低层南北向锋区；高层，南亚高压以及其北部的高空槽和潜热释放的反馈使南亚高压维持，从而加强了高层辐散及中尺度高空急流形成。这种系统间的相互作用为台风暴雨提供了低层辐合，高层辐散的动力条件。 利用角动量(M_g)和相当位温(θ_e)对条件性对称不稳定(CSI)进行定性判断，此次降雨过程的确存在对称不稳定和对流不稳定。根据滤波分析，对流不稳定和对称不稳定可产生重力惯性波。高层重力惯性波为频散波，与对称不稳定有关；低层为非频散波，与对流不稳定有关。高层重力惯性波向外强烈频散时，暴雨也相应较大。反映出对称不稳定和对流不稳定对降水有一定增辐作用。 采用Hoskins的位涡动力学框架，对9608号台风产生暴雨时期湿位涡的正压及斜压不稳定进行了诊断分析，看出：暴雨时，低层有正压位涡向斜压位涡的转换；高层有斜压位涡向正压位涡转换；在暴雨后期，低层有斜压位涡向正压位涡的转换。更多还原

【Abstract】 We made large numbers of statistical calculation and study about typhoon rainstorm from 1949 to 2000. The results shows: the decade difference of typhoon rainstorm was very remarkable.and it’s times was most in 1960’,Ieast in 1980’. In the 52 years,there are 51 rainstorms resulting from typhoon .about 1 rainstorm each year, most of them occurred in the summer( July and August).its landing place was mostly in JiangSu,ZheJiang,Fujian. Interaction,sub- interaction,non- Interaction turned and turned about 58.8%,23.5%,17.6%.In order to make clear the interaction between typhoon and mid-latitude system,we made numerical simulation test and physical diagnosis of 9608 typhoon in 1996.lt is found that in low layer,the connection between the subtropic high and typhoon periphery enhanced the low-level jet and transportation of water vapour. The south-north trough was formed and strengthened by the movement of cold air from NE to SW.In high level.upper trough on South Asia High and its north and release of potential heat made it maintained,therefore divergence at upper layer was enhanced ,and high jet was built. The interaction provided impetus condition for typhoon rainstorm through upper level convergence at the low layer and marked divergence at upper layer.some advantageous conditions resulted in the large-area rainstorm.Firstly.in large-scale background,typhoon conbined with westerly trough on mid-latitude and made long- time instability area on HuaBei because cold air infalling continuably from DongBei ;secondly,low level jet provided a large number of persistent vapor;finally, the puissant go-up air flow was carried through strong convergence at the low layer and marked divergence at upper layer.We estimated the conditional symmetry instability by absolute and geostrophic momentem(Mg) and comparative potential temperature. In this rain process, there was the symmetric and convection instability.By filtering calculation, the symmetric and convection instability can result in inertia-gravity wave.In high level ,its scatter connect with the symmetric instability ;in low level,its non- scatter connect with the convection instability. The symmetric and convection instability played the important role in increasing rain.By Hoskins’s dynamics frame of potential vorticity.diagnosis was performedabout vertical and inclined instability of potential vorticity when typhoon 9608 was bringing heavy rains.On the heavy rain time, potential vorticity of vertical press transformed partially into inclined potential-vorticity on low level. On the latter time of heavy rain .potential vorticity of inclined press transformed partially into vertical potential-vorticity on low level.更多还原