湛江港邻近海域台风浪的模拟研究

对第三代近岸海浪数值模式SWAN及包含的物理过程进行了简要介绍，利用该模式对影响南海湛江港海域的二次台风浪过程进行了模拟研究：由藤田台风风场模型同化相应时刻的台风要素、NCAR/NCEP网格点资料、单站观测资料后，提供模式所需风场；利用自嵌套的方式，提供模式波谱边界条件；两次模拟结果与实际海浪观测资料相符较好，可以为该海域台风浪的模拟预报提供较为重要的参考。     

2001年台风暴雨的分析

利用常规资料、HLAFS格点资料和GMS－5静止卫星红外云图，对2001年我国台风暴雨的天气气候特征、热带低压造成的“8.5”上海特大暴雨及0103号台风“榴莲”的强暴雨形成的物理条件进行了诊断分析研究，并探讨了动力学、热力学和大气层结稳定度等物理因子在这两次强暴雨过程中的主要作用。分析结果对实时预报业务和科研工作有一定启示意义。     

一种适于较强台风的切向风廓线方案及其对异常台风路径的数值模拟研究

针对现今台风数值预报中强热带气旋切向风廓线设计上的困难，提出了一种利用台风报告中7级风和10级风的半径来确定台风切向风廓线的方法。它既可反映真实台风外围结构又避免了强风速切变问题。该方案有可能改进台风尤其是异常路径台风的预报效果，具有广阔的业务应用前景。     

9806号台风非对称结构形成及其高纬西折路径分析

对9806号台风在弱环境场中的向北移动，至强环境场中折向西行的物理机制进行了分析，得出在弱环境场中台风可形成不对称结构，其物理量如高度的变化在台风进入强环境场后与环境场叠加，从而改变台风移向，强弱环境场的更替，可能是9806号台风移向突变的重要原因。     

THE STUDY OF STORM RAINFALL CAUSED BY INTERACTION BETWEEN THE NON-ZONAL HIGH LEVEL JET STREAK AND TYPHOON IN THE DISTANCE

In this paper, statistics were analyzed concerning correlation between the storm rainfall far from typhoon and non-zonal upper-level jet stream. The results show that the jet stream at 200 hPa is constantly SW (90.2 %) during the period in which storm rainfall occurs. Rainfall area lies in the right rear regions of the jet axes. While the storm intensifies, the jet tends to be stronger and turn non-zonal. With the MM4 model, numerical simulation and diagnosis were carried out for Typhoon No.9711 (Winnie) on August 19 to 20, 1997. The distant storm rainfall is tightly correlative to the jet and low-level typhoon trough. The divergence field of jet is related to the v component. The upper level can cause the allobaric wind convergence at low level. This is the result of the form of low-level typhoon trough and the strength of the storm. By scale analysis, it is found that there is a branch of middle scale transverse inverse circulation in the right entrance regions behind the jet below the 300-hPa level, which is very important to the maintenance and strengthening of storm rainfall. This branch of inverse circulation is relative to the reinforcement of jet's non-zonal characteristics. From the field of mesoscale divergence field and non-zonal wind field, we know that the stronger symmetry caused by transverse circulation in the two sides of the jet, rainfall’s feedback and reinforcement of jet’s non-zonal characteristics had lead to positive feedback mechanism that was favorable of storm rainfall’s strengthening.     

非常定自适应网格模式在台风路径数值预报中的应用

本文将作者在前文中介绍的非常定自适应网格模式用于台风路径的数值预报。由于自适应网格在台风中心附近安排了较密的网格，有效地提高了网格的分辨率，使得台风环流的结构在预报48小时以后仍能保持，其预报的路径与实况相比令人鼓舞。     

台湾岛地形对台风移动路径的作用

本文用一个β平面准地转正压模式实施了九组试验，研究台湾岛地形对台风移动路径的作用。初始场系根据SPECTRUM和TCM-90期间加强观测资料确定。结果表明:台湾岛地形的引进会使台风路径向右偏移；地形使台风环流的最大风速区向台风中心方向推移，造成台风环流空间尺度减小，这个结构的变化是路径右偏的一个可能原因。     

NUMERICAL SIMULATION OF MESOSCALE STRUCTURES OF TYPHOON AND OROGRAPHIC EFFECTS USING MM5*

The track,landfall,dynamic and thermodynamic and cloud-rain physical mesoscale structures and their evolution of typhoon HERB 1996 in 36 h from 0000 UTC 31 July to 1200 UTC 1 August 1996 were simulated by using the non-hydrostatic mesoscale model MM5.This period covered the process of typhoon HERB landfall at Taiwan and Fujian Provinces.Results show that the model successfully simulated the landfall process of typhoon HERB,revealed the most important characteristics of the mesoscale dynamic and thermodynamic and cloud-rain physical structure during its landfall.The simulated typhoon track was close to the observation.The center of cyclonic circulation simulated at 0000 UTC on 1 August 1996 (24 h integration) was located in shore near Fuqing,Fujian Province at which the typhoon was reported to landfall two hours later.It shows that strong upward motion formed by low level convergence existed in the eye-wall and subsidence at the eye.The wind field shows clear asymmetrical structure near the typhoon center.The cloud and rainband was screw-typed distributed around typhoon center,and consisted of meso-β scale rain cores.During the period of typhoon HERB staying near and passing over Taiwan,the lower cloud was developed in the eye region so that the previous clear typhoon eye on the satellite pictures became fuzzy.Observation shows that the typhoon center was "warm",but the model simulations with higher space resolution show that in the mid-troposphere the region of eye-wall with stronger upward motion and more cloud-and rain-water was warmer than the eye.During the period of typhoon passing over Taiwan and its following landfall at Fujian,the track of model typhoon deviated about 30 km northward (i.e.,rightward) because of the orographic effects of Taiwan Island,but the strength of the typhoon was not affected remarkably.The amount of rainfall on Taiwan in the 36 h simulations was enhanced more than six times by the orographic lifting of Taiwan Mountain.     

TYPHOON ACTIVITY IN NORTHWEST PACIFIC IN RELATION WITH EL NINO AND LA NINA EVENTS

Statistic and typical-year composition methods are used to study the northwest Pacific typhoon activities in relation with the EI Niño and La Niña events. The result indicates that the typhoon tends to be inactive in the EI Niño years and active in the La Niña years and it is also dependent on the onset and ending time and intensity of the events and areas of genesis of typhoons. With statistic features of the frequency of typhoon activity in the EI Niño and La Niña years and the time-lag correlation between the frequency and sea surface temperature(SST), useful information is provided for the prediction of typhoon occurrence. In addition, the singular values disassemble(SVD)method is applied to study the correlation between the geopotential field and SST field. The result shows that the air-sea coupling in the EI Niño years is unfavorable for the typhoon to develop. Which take place with a smaller number. Opposite situations are found with the La Niña years.     

台风“利奇马”不同强降水中心的雨滴谱特征分析

在2019年台风“利奇马”台风暖区、台风与西风槽相互作用区及西风槽影响区分别挑选4个极端强降水中心,利用各站连续观测分钟雨滴谱资料和分钟降水资料,分析了不同站点和不同降水时段的雨滴尺度谱、雨滴速度谱、雨滴尺度—时间谱和雨滴速度—时间谱特征,研究了雨滴谱特征随时间的变化。结果表明:4个降水中心的雨滴尺度—时间谱和雨滴速度—时间谱存在明显差异,而过程的统计谱特征差异不明显;过程中不同区域的站点、同一站点不同的降水时段,雨滴尺度谱和雨滴速度谱主要为双峰型,尺度谱双峰中各站对应1.2 mm直径峰的位置一致,处于较小尺度峰的位置不一致;在较大雨强时,雨滴尺度谱上会出现单峰和三峰的情况,但比例较少;1.2 mm雨滴的高浓度区域与地面降水强度有非常好的对应关系,在1.2 mm雨滴的高浓度区域形成的过程中,地面降水逐渐增强,随着1.2 mm雨滴的高浓度区域逐渐瓦解,地面降水逐渐减弱,直至出现间歇。