东北太平洋和北大西洋热带云团发展率特征的对比

Comparison of the Characteristics of the Development of Tropical Cloud Clusters between the Northeast Pacific and the North Atlantic

热带云团(Tropical Cloud Cluster,TCC)和热带气旋(Tropical Cyclone,TC)是热带地区的重要天气系统,对热带地区的农业活动可以产生重要的影响。TCC是TC的初始胚胎状态,可以在适宜的环境条件下发展为TC,TCC的发展率可以用来定量地表征能够发展为TC的TCC所占的比例。东北太平洋和北大西洋是西半球TCC和TC活动活跃的海域。利用1982—2018年的TCC和TC数据,对东北太平洋和北大西洋海域TCC发展率的变异特征进行了对比。结果显示:在季节变化方面,东北太平洋的TCC发展率在7月份达到最大值(13.22%),北大西洋的TCC发展率在9月份达到最大值(16.09%);在年际变化方面,东北太平洋和北大西洋海域TCC发展率时间序列的相关性并不显著;在长期变化趋势方面,东北太平洋TCC发展率呈显著的减少趋势,而北大西洋TCC发展率呈不显著的减少趋势。这些研究结果有助于更好地认识东北太平洋和北大西洋海域TCC发展率的变异特征。

Tropical cloud cluster(TCC)and tropical cyclone(TC) are important tropical weather systems, which could have important impacts on agricultural activities in the tropical region. As the initial embryonic state of the TC, a TCC could develop into a TC under suitable environmental conditions.The genesis productivity(GP) of the TCC can be used to quantitatively characterize the proportion of the TCC that can develop into the TC. The northeast Pacific and the North Atlantic are active regions of TCC and TC in the western hemisphere. In this study, TCC and TC data from 1982 to 2018 were used to compare the variation characteristics of the TCC GP between the northeast Pacific and the North Atlantic. In terms of seasonal variation,the TCC GP in the northeast Pacific reached its maximum in July(13.22%), and that in the North Atlantic peaked in September(16.09%). In terms of interannual variation,the correlations between the time series of TCC GP in the northeast Pacific and the North Atlantic were not significant. In terms of long-term changing trend, the TCC GP in the northeast Pacific showed a significant decreasing trend, while that in the North Atlantic showed an insignificant decreasing trend. These results are helpful to better understand the variation characteristics of the TCC GP in the northeast Pacific and North Atlantic.