Articles | Volume 32, issue 3
https://doi.org/10.5194/npg-32-309-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/npg-32-309-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
10 Sep 2025
Research article |
| 10 Sep 2025
| 10 Sep 2025
Exploring complexity measures for analysis of solar wind structures and streams
Venla Koikkalainen
CORRESPONDING AUTHOR
Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland
Emilia Kilpua
Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland
Simon Good
Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland
Adnane Osmane
Department of Physics, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland
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Short summary
We study time series of solar wind large-scale structures (magnetic clouds, sheaths, slow and fast streams). These have profound importance with regard to causing disturbances in the heliospheric conditions and driving space weather on Earth. The used techniques include methods derived from information theory to determine entropy and complexity. We find that all of these techniques show stochastic fluctuations, but magnetic clouds stand out due to their coherent magnetic field.
We study time series of solar wind large-scale structures (magnetic clouds, sheaths, slow and...
