SYNCHRONIZATION OF HEMISPHERIC SUNSPOT ACTIVITY REVISITED: WAVELET TRANSFORM ANALYSES

	SYNCHRONIZATION OF HEMISPHERIC SUNSPOT ACTIVITY REVISITED: WAVELET TRANSFORM ANALYSES
	Li KJ(李可军)1; Gao PX(高朋鑫)1,2 ; Zhan, LS(占腊生)1
刊名	ASTROPHYSICAL JOURNAL
	2009-01-20
卷号	691 期号:1 页码:537-546
关键词	Sun: activity Sun: general sunspots
ISSN号	0004-637X
通讯作者	Li, K (reprint author), CAS, Yunnan Observ, Natl Astron Observ, Kunming 650011, Peoples R China.
产权排序	第一完成单位
英文摘要	Three kinds of wavelet transform methods-continuous wavelet transform, cross-wavelet transform, and wavelet coherence-have been proposed to investigate the phase synchrony of the smoothed monthly mean sunspot areas in the time interval of 1874 May to 2008 March in the solar northern and southern hemispheres. For both time series, the Schwabe cycle is the only period of statistical significance, whose mean value is 10.61 yr. The length of the Schwabe cycle for the smoothed monthly mean sunspot areas in the northern hemisphere actually differs from that in the southern hemisphere, which should lead to phase asynchrony between the two series. Both the cross-wavelet transform and wavelet coherence analyses show an asynchronous behavior with phase mixing in the high-frequency components of hemispheric sunspot activity and a strong synchronous behavior with coherent phase angles in the low-frequency components corresponding to period scales around the Schwabe cycle. Although a phase coherence is found at timescales of about 8.5-13.5 yr (which is similar to those of Donner & Thiel, but within a shorter period), phases are not always coherent at the timescales in the considered time interval. The availability of a physical, meaningful phase definition depends crucially on the appropriate choice of reference frequencies. At the coherent period scales, the leading role is found from those conditions where processes of sunspot formation in the northern hemisphere occur earlier than in the southern one (except some exceptions in several years around the year 1900) during the years of about 1874-1926 to those where the opposite is true during the years of about 1926-1966, and returning back again during the years of about 1966-2008. The mean phase synchronization values at the coherent timescales given by wavelet coherence represent the running trend of the line of synchronization given by a cross-recurrence plot.
学科主题	Astronomy & Astrophysics
WOS标题词	Science & Technology ; Physical Sciences
类目[WOS]	Astronomy & Astrophysics
研究领域[WOS]	Astronomy & Astrophysics
关键词[WOS]	RECURRENCE PLOTS ; TIME-SERIES ; COHERENCE ; SYSTEMS
收录类别	SCI
原文出处	http://iopscience.iop.org/0004-637X/691/1/537/
语种	英语
WOS记录号	WOS:000263196600047
公开日期	2016-05-03
内容类型	期刊论文
源URL	[http://ir.ynao.ac.cn/handle/114a53/6152]
专题	云南天文台_太阳物理研究组
作者单位	1.National Astronomical Observatories/Yunnan Observatory, CAS, Kunming 650011, China 2.Graduate School, CAS, Beijing 100863, China 3.Jingdezhen Ceramic College, Jingdezhen 330001, China
推荐引用方式 GB/T 7714	Li KJ,Gao PX,Zhan, LS. SYNCHRONIZATION OF HEMISPHERIC SUNSPOT ACTIVITY REVISITED: WAVELET TRANSFORM ANALYSES[J]. ASTROPHYSICAL JOURNAL,2009,691(1):537-546.
APA	Li KJ,Gao PX,&Zhan, LS.(2009).SYNCHRONIZATION OF HEMISPHERIC SUNSPOT ACTIVITY REVISITED: WAVELET TRANSFORM ANALYSES.ASTROPHYSICAL JOURNAL,691(1),537-546.
MLA	Li KJ,et al."SYNCHRONIZATION OF HEMISPHERIC SUNSPOT ACTIVITY REVISITED: WAVELET TRANSFORM ANALYSES".ASTROPHYSICAL JOURNAL 691.1(2009):537-546.