西北太平洋转向路径和西北移路径登陆台风的水汽输送特征对比分析

Comparison of Water Vapor Transport Characteristics for Turning and Northwestward Track Landing Typhoon in the Western North Pacific

本文基于热带气旋最佳路径资料和再分析资料,利用有限混合模型(Finite Mixture Model, FMM)聚类分析方法将西北太平洋台风(Typhoon, TY)路径分为四类,并通过动态合成方法研究了转向路径与西北移路径强台风登陆前后其周围环境气流及水汽输送特征,研究结果表明:将西北太平洋台风分为转向路径台风、西北移路径台风、异常路径台风和曲线路径台风。转向路径的台风与强台风的个数最多,登陆以后维持的时间最长;西北移路径台风登陆的频数最多。异常路径与曲线路径台风偏东偏南,且频数较少,极少登陆。相较于西北移路径强台风,转向路径的强台风在登陆前后的强度更强,暖心结构更明显,得到的水汽输送更充沛,因此在登陆后能够维持更久的时间。

Based on the tropical cyclone best track data and reanalysis data, this paper divides typhoon (TY) into four categories by using the Finite Mixture Model cluster method on the Western North Pacific. The circulation and the vapor transport around intense typhoon (ITY) before and after the landfall are explored by the dynamic synthesis method. The conclusions are as follows: the TY are divided into turning TY, northwestward TY, abnormal path TY and curve path TY. The turning TY, with the most frequency of TY and ITY, has longer duration than others after landfall. And the northwest-ward TY has the greatest number of landfall TY. The last two types are generated farther east and south than those in the first two groups, with much smaller frequency and chance to make landfall. Compared with the ITY of the northwest typhoon, no matter landfall or not, the turning track ITY has longer duration accompanied by more abundant water vapor and warmer core.