The Implication of Solar-Geophysical Parameters on Small-Amplitude Forbush Decreases

Authors

Keywords:

Cosmic Rays, Forbush Decreases, Small-Amplitude Events, Manual Method, Automated Method, Cosmic Ray Stations

Abstract

Forbush decreases (FDs) are rapid, short-term reductions in cosmic ray (CR) intensity, frequently used in space weather research. However, identifying and calculating the magnitude and timing of these events remains a significant challenge. The current manual approach is subjective and inefficient, as it cannot process large datasets. Consequently, automated methods for FD selection are necessary to overcome the limitations of manual event lists. Our group has published a fully automated Forbush decrease (FD) event list, comprising high- and low-amplitude events recorded by the Moscow and Oulu neutron monitors. This catalog facilitates statistical investigations into the relationship between FDs and solar-geomagnetic variables. In this study, we analyze the small-amplitude events and demonstrate that Earth’s atmospheric phenomena modulate weak FDs, whereas interplanetary magnetic field conditions appear to have a lesser effect.  

Dimensions

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Published

2026-09-16

How to Cite

Okike, O., Ikoro, M. O., Akande-Rowland, P. I., Chikwendu, A. O., & Okorie, E. M. (2026). The Implication of Solar-Geophysical Parameters on Small-Amplitude Forbush Decreases. Nigerian Journal of Physics, 35(S), 294-302. https://doi.org/10.62292/njp.v35(s).2026.698

Issue

Vol. 35 No. S (2026): Nigerian Journal of Physics - Vol. 35(S)

Section

Articles
Copyright & Licensing

Copyright (c) 2026 Ogbos Okike, Miracle Okoro Ikoro, Patience Ifeyinwa Akande-Rowland, Augustine Ogonna Chikwendu, Esther Mark Okorie

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

How to Cite

Okike, O., Ikoro, M. O., Akande-Rowland, P. I., Chikwendu, A. O., & Okorie, E. M. (2026). The Implication of Solar-Geophysical Parameters on Small-Amplitude Forbush Decreases. Nigerian Journal of Physics, 35(S), 294-302. https://doi.org/10.62292/njp.v35(s).2026.698

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