Long term variability in solar wind velocity and IMF intensity and the relationship between solar wind parameters & geomagnetic activity

被引：0
作者：
G. K. Rangarajan
L. M. Barreto
机构：
[1] Observatorio Nacional São Cristovao,
来源：
Earth, Planets and Space | 2000年 / 52卷
关键词：
Solar Wind; Solar Cycle; Coronal Hole; Geomagnetic Activity; Solar Minimum;
D O I：
暂无
中图分类号：
学科分类号：
摘要：
A study is carried out on the mean monthly values of in situ observations of solar wind velocity (V) and the intensity of interplanetary magnetic field, B to elucidate their long term variations using the technique of singular spectrum analysis. It is shown that B exhibits a clear solar cycle signal with progressively deepening minimum and a well-defined longer period variation but V is marked by a ~9-yr cycle. Time variations in the amplitude of 16-month periodicity, observed sporadically in the velocity earlier by others are clearly brought out, as also the characteristic amplitude changes in a 42-month signal in velocity. It appears that time intervals which show certain significant fluctuations in B are marked by the absence of similar signal in V.
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页码：121 / 132
页数：11
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