2015年西北太平洋和南海台风活动特征及主要预报技术难点

The activity characteristics and forecasting difficulties of tropical cyclones over Western North Pacific and South China Sea in 2015

利用常规气象观测资料、1949—2015年中国气象局台风最佳路径资料、2015年中日美台风实时定位资料、1°×1°的NOAA/OISST月平均海温资料和NCEP/FNL再分析资料以及0.5°×0.5°的NCEP-RTG实时海温等资料,对2015年西北太平洋和南海台风活动的主要特征、厄尔尼诺对该年台风整体活动的影响、1508号台风"鲸鱼"实时定位、1522号台风"彩虹"近海急剧加强预报、1510号台风"莲花"和1521号台风"杜鹃"长时效路径预报以及地面观测系统存在的薄弱环节等主要业务技术难点和问题进行了初步分析。结果表明:1)2015年台风活动活跃期不明显,呈现生成总数与多年平均持平、南海台风偏少、生成源地偏东、强度强、超强台风异常偏多、登陆个数及频次偏少等特征。2)2015年台风主要活动特征与极强厄尔尼诺事件关系密切,但厄尔尼诺对台风的影响不是单一的,其影响物理机制尚待深入研究。3)台风"鲸鱼"实时业务定位的精度直接影响其登陆预报的精度,综合应用多源观测资料、规范台风定位业务流程,有利于台风定位和路径预报精度的提高。4)台风快速增强和路径长时效预报仍是台风业务的主要技术瓶颈,高分辨率台风-海-气-浪耦合模式、集合预报及相关动力统计模式和天气物理概念模型的研发改进将是未来的主要解决技术途径。5)中国地面观测系统尚不具备对极端台风的监测能力,在沿海受台风影响的重点区域(包括海岛)布设先进的重型机械式强风仪,将有助于提高对极端台风事件的监测能力。

By using conventional observational data, CMA Tropical Cyclone Best Track Dataset from 1949 to 2015, real time track by CMA, Japan Meteorological Agency （JMA） and Joint Typhoon Warning Center （JTWC） , monthly NOAA optimum interpolation sea surface temperature data （1°×1°）, NCEP FNL reanalysis data （1°×1°） and NCEP real-time global sea surface temperature data （0.5°×0.5°）, some preliminary analyses are made about the main forecasting technical difficulties and problems for operational TC forecasting and warning in 2015, such as the main activity characteristics of TCs over Western North Pacific and South China Sea, the influence of E1 Nino on TC activity, the real time operational positioning for Typhoon Kujira （ 1508 ）, the rapid intensification forecasting of Typhoon Mujigae （1522） over coastal waters, the long time track forecasting for Typhoon Linfa （1510） and Typhoon Dujuan （1521） and some weaknesses in surface observation system. The results show that： 1 ） There is not an obvious active stage during 2015 TC season, which is characterized by： almost same annual formation frequency as the long-time average, fewer TCs over South China Sea, more easterly TC origins, stronger intensity, abnormally more super typhoons, fewer landing number and lower landing frequency and so on. 2） The main TC activity characteristics in 2015 are closely related to the strong E1 Nino event, and its physical mechanism is still to be further studied. 3 ） The accuracy of real-time operational positioning of Typhoon Kujira （1508） directly affected its landing forecasting.The application of multi-source observation data and the standardized operational TC positioning flow is usefull for improving TC positioning and track forecasting. 4 ） The rapid intensification and long-term track forecasting are still major technical bottlenecks in operational TC forecasting and warning, and the development of TC high-resolution sea-air-wave coupling model, ensemble forecast, dynamic statistical model and synoptic physics concept model will be the main technical approach in future. 5 ） Current surface observation network in China does not have the ability to monitor extreme TCs, and it could be improved by deploying more advanced heavy-duty mechanical strong wind anemograph in key coastal areas （including islands） affected by TCs.