STATISTICAL STUDY OF STRONG AND EXTREME GEOMAGNETIC DISTURBANCES AND SOLAR CYCLE CHARACTERISTICS

	STATISTICAL STUDY OF STRONG AND EXTREME GEOMAGNETIC DISTURBANCES AND SOLAR CYCLE CHARACTERISTICS
	Kilpua, E. K. J.; Olspert, N.; Grigorievskiy, A.; Kapyla, M. J.; Tanskanen, E. I.; Miyahara, H.; Kataoka, R.; Pelt, J.; Liu, Y. D.
刊名	ASTROPHYSICAL JOURNAL
	2015
卷号	806 期号:2 页码:272
关键词	dynamo solar-terrestrial relations Sun: activity Sun: coronal mass ejections (CMEs) sunspots
ISSN号	0004-637X
通讯作者	Kilpua, EKJ (reprint author), Univ Helsinki, Dept Phys, FIN-00014 Helsinki, Finland.
英文摘要	We study the relation between strong and extreme geomagnetic storms and solar cycle characteristics. The analysis uses an extensive geomagnetic index AA data set spanning over 150 yr. complemented by the Kakioka magnetometer recordings. We apply Pearson correlation statistics and estimate the significance of the correlation with a bootstrapping technique. We show that the correlation between the storm occurrence and the strength of the solar cycle decreases from a clear positive correlation with increasing storm magnitude toward a negligible relationship. Hence, the quieter Sun can also launch superstorms that may lead to significant societal and economic impact. Our results show that while weaker storms occur most frequently in the declining phase, the stronger storms have the tendency to occur near solar maximum. Our analysis suggests that the most extreme solar eruptions do not have a direct connection between the solar large-scale dynamo-generated magnetic field, but are rather associated with smaller-scale dynamo and resulting turbulent magnetic fields. The phase distributions of sunspots and storms becoming increasingly in phase with increasing storm strength, on the other hand, may indicate that the extreme storms are related to the toroidal component of the solar large-scale field.
收录类别	SCI
语种	英语
内容类型	期刊论文
源URL	[http://ir.nssc.ac.cn/handle/122/4583]
专题	国家空间科学中心_空间科学部
推荐引用方式 GB/T 7714	Kilpua, E. K. J.,Olspert, N.,Grigorievskiy, A.,et al. STATISTICAL STUDY OF STRONG AND EXTREME GEOMAGNETIC DISTURBANCES AND SOLAR CYCLE CHARACTERISTICS[J]. ASTROPHYSICAL JOURNAL,2015,806(2):272.
APA	Kilpua, E. K. J..,Olspert, N..,Grigorievskiy, A..,Kapyla, M. J..,Tanskanen, E. I..,...&Liu, Y. D..(2015).STATISTICAL STUDY OF STRONG AND EXTREME GEOMAGNETIC DISTURBANCES AND SOLAR CYCLE CHARACTERISTICS.ASTROPHYSICAL JOURNAL,806(2),272.
MLA	Kilpua, E. K. J.,et al."STATISTICAL STUDY OF STRONG AND EXTREME GEOMAGNETIC DISTURBANCES AND SOLAR CYCLE CHARACTERISTICS".ASTROPHYSICAL JOURNAL 806.2(2015):272.