地磁暴前地面宇宙线强度变化Morlet小波特征分析

	地磁暴前地面宇宙线强度变化Morlet小波特征分析
	苗娟 ; 薛炳森 ; 叶宗海
刊名	空间科学学报
	2003
卷号	23 期号:6 页码:452-458
关键词	小波变换宇宙线强度地磁暴
ISSN号	0254-6124
其他题名	THE WAVELET CHARACTER OF COSMIC RAY INTENSITY BEFORE GEOMAGNETIC STROMS
通讯作者	北京8701信箱
中文摘要	用Morlet小波变换对Oulu台站和Apatity台站(主要是Apatity台站)1998-2002年间宇宙线静日和地磁暴前的地面宇宙线强度变化特征进行分析,得到:在宇宙线静日期间普遍存在准24 h周期变化特征,并且在当地时间0200,1400左右分别出现最小值和最大值;对12个例子的分析可以看到地面宇宙线强度在地磁暴之前1-2天均出现了不同于宇宙线静日期间变化特征,或有小尺度周期出现,或周期变化完全消失,或有异常24h周期变化,这种变化特征在一定程度上可作为地磁预报的先兆特征之一.
英文摘要	In this paper, Morlet wavelet is applied to analyze the character of cosmic ray intensity of Apathy station (latitude: 67.560N, longitude: 33.40E, Russia and Oulu station (latitude: 65.050N, longitude:25.470E, Finland) respectively during quiet period of geomagnetic field and before geomagnetic storms from 1998 to 2002.Four-teen examples are selected including two examples of quiet period and 12 examples before geomagnetic storms. The level of major storms selected in this paper is that index Dst is less than一100 nT. By Morlet wavelet transform,cosmic ray intensity of different condition shows different variety. Results show that 24 h periodicity exists and is distinct during quiet time, and usually minimum value of cosmic ray in- tensity appears around about 0200 local time and maximum value appears around about 1400 local time; Twelve examples before geomagnetic storms period show that variety of 24 h periodicity all change.Some minish, some disappear, and some have anomalous 24 h periodicity, and these varieties differ from that of quiet time.These characters before geomagnetic storms may provide a sign that can be used to forecast the coming of geomagnetic storms of coming of geomagnetic storms.
学科主题	空间环境
资助信息	国家重点基础研究发展规划项目
语种	中文
内容类型	期刊论文
源URL	[http://ir.cssar.ac.cn/handle/122/398]
专题	国家空间科学中心_空间环境部
推荐引用方式 GB/T 7714	苗娟,薛炳森,叶宗海. 地磁暴前地面宇宙线强度变化Morlet小波特征分析[J]. 空间科学学报,2003,23(6):452-458.
APA	苗娟,薛炳森,&叶宗海.(2003).地磁暴前地面宇宙线强度变化Morlet小波特征分析.空间科学学报,23(6),452-458.
MLA	苗娟,et al."地磁暴前地面宇宙线强度变化Morlet小波特征分析".空间科学学报 23.6(2003):452-458.