台风菲特暴雨诊断分析  

Diagnosis of Heavy Rainfall Associated with Typhoon Fitow

作　　者：刘建勇 周冠博 顾思南 王毅 郭建民 

机构地区：[1]浙江省宁波市气象台,宁波315012 [2]国家气象中心,北京100081

出　　处：《气象科技》2014年第6期1047-1056,共10页Meteorological Science and Technology

基　　金：国家公益性行业专项(GYHY201006004);国家重点基础研究发展计划(973)项目(2009CB421500);国家自然科学基金(41405051);浙江省重大科技专项(2011C13044)共同资助

摘　　要："菲特"台风暴雨具有阶段性特征,包括台风远距离降水、台风倒槽和内螺旋雨带降水、台风外部螺旋雨带降水、台风残留低压环流与冷空气相互作用降水4个阶段。利用地面观测、气象雷达观测、NCEP分析资料,对"菲特"台风暴雨环流形势进行了分析。引导台风东移的高压东西部具有不同热力属性,东部暖性深厚、西部冷性浅薄。浅薄冷高压阻挡登陆台风继续西移,延长台风倒槽和外围螺旋雨带的降水时间。"丹娜丝"台风的靠近,有利于东南风水汽输送的增强。副热带高压的增强,在黄海上空逼近东移高空槽形成稳定的高空急流。文章提出与传统垂直风切变大、高空急流强的冷空气阻挡型不同的侵入型冷空气和台风相互作用形势。侵入型冷空气从低层入侵,影响台风残留低压的外围环流。在低压外围环流的北部形成较强的东北风,并与海上的东风对峙辐合形成海岸锋。冷空气侵入型的空间不对称特征明显:对流有效位能东高西低,垂直风切变西北高东南低。残留低压的中层受冷空气影响较小,沿海地区的东南风持续的时间更长。中层高位涡区与地面海岸锋的互应,为变性的台风残留低压暴雨提供有利条件。The Typhoon Fitow experienced four rainfall stages： typhoon peripheral precipitation, rainfall caused by the typhoon inverted trough and typhoon itself, rear spiral rain-band rainfall, and rainfall originating from the interaction between outside circulation of the residual low pressure and the cold air. Using the data of surface observation, weather radar, and NCEP analysis, the rainstorm circulation forms of Fitow are analyzed. The east and west sides of high pressure, which guided the eastwards movement of typhoon, had different thermal properties. The east side was warm and deep, while the west side was cold and shallow. The shallow cold high pressure prevented the westward movement after landfalling, leading to the persistent rainfall under the typhoon inverted trough and in the rear spiral rain band. The approaching of typhoon Danas was beneficial to the enhancement of water vapor transfer with southeast winds. The interaction between typhoon and the osmotic cold air, which was different from the traditional detaining cold air with large vertical wind shear and a strong upper-level jet stream, was discussed. The osmotic cold air invaded from the lower layer and affected the outside circulation of residual low pressure of typhoon. The strong northeast winds formed in the north of outside circulation of low pressur; and converged with the east winds from the sea, which formed the coastal front. The spatial asymmctry characteristics of the osmotic cold air were obvious： convective available potential energy was high in the east and low in the west, and the vertical wind shear was high in the northwest and low in the northeast. The cold air had only small influence on the middle layer of the residual low pressure, so the southeast winds in the coastal area existed for a longer time. The interaction between high potential vorticity area in the middle layer and the coastal front on the surface provided good conditions for the residual low pressure rainstorm of extra-tropical transition.

关 键 词：台风 暴雨 冷空气 双台风 

分 类 号：P444[天文地球—大气科学及气象学]