台风“摩羯”和“利奇马”经渤海强度变化特征分析  

Characteristic Analysis of Intensity Variation of Typhoon Yagi and Lekima above Bohai Sea

作　　者：朱男男 左涛 苏杭 ZHU Nannan;ZUO Tao;SU Hang(Tianjin Marine Meteorological Centre,Tianjin 300074;Tianjin Key Laboratory for Oceanic Meteorology,Tianjin 300074)

机构地区：[1]天津海洋中心气象台,天津300074 [2]天津市海洋气象重点实验室,天津300074

出　　处：《气象科技》2022年第2期214-223,共10页Meteorological Science and Technology

基　　金：国家自然科学基金(41675046)资助;国家重点研发计划重点专项(2019YFC1510100);中国气象局预报员专项(CMAYBY2020-006)资助。

摘　　要：利用FY-4水汽云图、NCEP/FNL资料、自动站资料和ERA-Interim海温资料,分析入海增强台风“摩羯”(1814)和入海减弱台风“利奇马”(1909)经过渤海强度变化特征。结论如下:台风“摩羯”中心入海增强过程伴随着中高层冷空气侵入,冷空气深入“摩羯”云系中心,台风强度减弱并逐渐消亡。台风“利奇马”入海前冷空气已经侵入台风中心,台风入海后强度减弱,暖心结构变得不对称,低层有清晰的斜压特征。“摩羯”入海前渤海上空为强辐散区,“利奇马”入海前渤海上空为弱辐合场,北上前进方向出现高空辐散有利于台风加强。台风登陆前垂直风切变与台风强度反位相分布,北上后台风垂直风切变与台风强度同位相分布。“摩羯”入海后水汽通道出现断裂,其入海增强更多依赖于热力条件和动力条件。“利奇马”水汽通量和水汽通量散度源于自身环流的贡献。台风“摩羯”入海后潜热加热率激增,“利奇马”低层维持弱潜热加热直至台风消亡。FY-4 satellite cloud images, the hourly surface AWS data, NCEP-FNL reanalysis data and ERA-Interim SST data are used for analyzing intensity characteristics of Typhoon Yagi(1814) and typhoon Lekima(1909) above the Bohai Sea. The results show that Yagi’s intensification was accompanied by the invasion of cold air in the middle and upper layers. When the cold air invaded the centre of the typhoon cloud, the intensity of typhoon Yagi weakened. Before the typhoon Lekima entered the sea, the cold air had intruded into the typhoon’s centre;the typhoon weakened and died after entering the ocean. The warm-core structure of the northward typhoon was destroyed, and the symmetrical structure became asymmetrical. The lower level of the typhoon showed baroclinic characteristics. Typhoon Yagi entered a strong divergence zone through the Bohai Sea. However, the Lekima entered a weak convergence field through the Bohai Sea. The high-altitude divergence in the northward direction was conducive to the strengthening of the typhoon before the typhoon lands. The vertical wind shear and the typhoon intensity were distributed opposite, but the position conversed when the typhoons land. After Yagi entered the sea, the water vapour channel was broken, and its strength above the sea was more dependent on thermal and dynamic conditions. The water vapour flux and water vapour flux divergence of Typhoon Lekima originated from its circulation. After Yagi entered the sea, the latent heat heating rate increased sharply. The lower layer of the Lekima maintained a weak latent heating centre until the typhoon disappears.

关 键 词：北上台风 FY-4水汽图像 暖心结构 潜热加热率 垂直风切变 渤海海温 

分 类 号：P458[天文地球—大气科学及气象学]