影响中国大陆热带气旋路径分类及其特征研究

热带气旋(TC)是影响中国的重要天气系统,对TC路径分类有助于认识热带气旋的活动特征。本文采用中国气象局热带气旋资料中心提供的1949至2016年6—11月最佳TC路径资料,选取TC质心、生命史、转向、强度等特征参数,利用K-means聚类方法将影响中国大陆的热带气旋分为4类。对4类路径进行比对分析后发现各类TC的走向、生命史、活动季节、登陆概率及区域等特征差异显著,TC单体强度和生命史在强厄尔尼诺发展年也有不同程度的增强。在年代际变化上,1998年以来,尽管各类TC频数变化趋势不同,但各类TC单体能量耗散指数均有不同程度的增长趋势,这可能与近年来强厄尔尼诺发展有关。

Study on the classification and characteristics of tropical cyclone tracks in mainland China

Tropical Cyclone (TC) is an important tropical weather system that affects mainland China. Classification for tropical cyclone tracks is conducive to the study of its characteristics. This paper is based on the best track data from 1949 to 2016 (from June to November) provided by the Shanghai Typhoon Institute of, CMA. TCs affecting mainland China are classified into 4 clusters by K-means based on parameters such as centroids, life spans, steering and intensities. There is obvious distinction between clusters in tracks, life spans, seasonal patterns and landing frequency and regions. During the development of strong El Nino, the intensity and life span of each cluster of TC also increase in different degrees. In terms of the climatic trend, although each cluster shows different tendency in frequency, the single PDI are all in an ascending tendency since 1998, which may be attributed to the development of strong El Nino in recent years.