The Variation of SolarWind Correlation Lengths Over
Three Solar Cycles
Three Solar Cycles
File(s)
Accepted version
Author(s)
Wicks, RT
Owens, MJ
Horbury, TS
Type
Journal Article
Abstract
We present the results of a study of solar wind velocity and magnetic field correlation lengths over the last 35 years. The correlation length of the magnetic field magnitude λ|B| increases on average by a factor of two at solar maxima compared to solar minima. The correlation lengths of the components of the magnetic field λBXYZ and of the velocity λVYZ do not show this change and have similar values, indicating a continual turbulent correlation length of around 1.4 × 106 km. We conclude that a linear relation between λ|B|, VB2, and Kp suggests that the former is related to the total magnetic energy in the solar wind and an estimate of the average size of geoeffective structures, which is, in turn, proportional
to VB2. By looking at the distribution of daily correlation lengths we show that the solar
minimum values of λ|B| correspond to the turbulent outer scale. A tail of larger λ|B| values is present at solar maximum causing the increase in mean value.
to VB2. By looking at the distribution of daily correlation lengths we show that the solar
minimum values of λ|B| correspond to the turbulent outer scale. A tail of larger λ|B| values is present at solar maximum causing the increase in mean value.
Date Issued
2010-02-13
Citation
Solar Physics, 2010, 262, pp.191-198
ISSN
0038-0938
Publisher
Springer Science+Business Media B.V.
Start Page
191
End Page
198
Journal / Book Title
Solar Physics
Volume
262
Issue
1
Copyright Statement
© Springer Science+Business Media B.V. 2010. The final publication is available at link.springer.com
Description
12.12.13 KB. Ok to add accepted version to spiral, embargo period elapsed.
Identifier
http://www3.imperial.ac.uk/people/r.wicks
Subjects
solar wind
turbulence
solar cycle
Publication Status
Published
Coverage Spatial
UK