基于CEEMD-SSWT对太阳南北半球Rieger-type周期的不对称性分析  

Asymmetry Analysis of Solar Northern and Southern Hemisphere Rieger-type Period Based on CEEMD-SSWT

作　　者：卢煊 薛雅娟[1] 邓林华 LU Xuan;XUE Ya-juan;DENG Lin-hua(School of Communication Engineering,Chengdu University of Information Technology,Chengdu 610200;School of Mathematics and Computer Science,Yunnan Minzu University,Kunming 650000)

机构地区：[1]成都信息工程大学通信工程学院,成都610200 [2]云南民族大学数学与计算机科学学院,昆明650000

出　　处：《天文学报》2024年第6期1-14,共14页Acta Astronomica Sinica

基　　金：四川省自然科学基金项目(2023NSFSC0258);云南省基础研究计划项目(202301AV070007)资助。

摘　　要：CEEMD(Complete Ensemble Empirical Mode Decomposition)是近年提出的一种自适应滤波算法,SSWT(Synchrosqueezed Wavelet Transform)是目前的一种高分辨率时频分析算法.采用CEEMD对太阳黑子日面积数据进行预滤波处理,再利用SSWT进行太阳南北半球Rieger-type周期不对称性分析,实现对太阳周期信号更精确的提取.研究结果表明:(1)虽然整个北半球的活动强度要高于南半球,但其整个13个活动周的Rieger-type周期信号的平均周期尺度却是极其相近的;(2)南北半球的太阳活动强度明显不对称,但在大部分活动周中,在太阳活动的极大期也是南北半球太阳活动不对称性最弱的时期;(3)太阳活动的强度与太阳的Rieger-type周期信号平均周期没有明显的相关关系,并不是在每个活动周中太阳活动强度越高的半球,所对应的半球Rieger-type周期信号的平均周期就一定越小,活动强度越低所对应的半球Rieger-type周期信号的平均周期就一定越大;(4)Rieger-type周期通常出现在太阳活动的极大期附近,但在某些活动周中Rieger-type周期会呈现多次波动,也会出现在太阳活动的上升期或下降期.CEEMD(Complete Ensemble Empirical Mode Decomposition)is an adaptivefiltering al-gorithm proposed in recent years,and SSWT(Synchrosqueezed Wavelet Transform)is a current high-resolution time-frequency analysis algorithm.In this paper,CEEMD is used to pre-filter the sunspot daily area data,and then SSWT is used to analyze the Rieger-type period asymmetry of the northern and southern hemispheres to achieve a more accurate extraction of the solar period signal.The results show that:(1)although the intensity of activity is higher in the Northern Hemisphere than in the Southern Hemisphere as a whole,the mean period scales of the Rieger-type period signal for the entire 13 active cycles of the two hemispheres are extremely similar.(2)There is a clear asymmetry in the intensity of solar activity between the northern and southern hemispheres,but during most of the active weeks,the period of maximum solar activity is also the period of weakest asymmetry between the northern and southern hemispheres.(3)There is no clear correlation between the intensity of solar activity and the mean period of the solar Rieger-type period signal,and it does not follow that the higher the intensity of activity,the smaller the mean period of the Rieger-type period signal in the corresponding hemisphere,and the lower the intensity of activity,the larger the mean period of the Rieger-type period signal in the corresponding hemisphere.(4)The Rieger-type period usually occurs near the maximum period of solar activity,but in some cycles the Rieger-type period shows multiplefluctuations and can also occur during periods of rising or falling solar activity.

关 键 词：太阳:活动 太阳:黑子 技术:CEEMD-SSWT 

分 类 号：P182[天文地球—天文学]