Predicted amplitude of the next solar cycle 26 using the strength of current solar cycle 25 as precursor

1Pishkalo, MI
1Main Astronomical Observatory of the National Academy of Sciences of Ukraine, Kyiv, Ukraine
Space Sci. & Technol. 2025, 31 ;(5):50-54
https://doi.org/10.15407/knit2025.05.050
Publication Language: English
Abstract: 
Solar activity affects space weather and many space-borne and ground-based high-technological systems. Knowing the solar activity level in advance is important for modern humans’ lives. Among the many methods proposed to date for the prediction of the strength of the next solar cycle, the most in demand are the numerous precursor methods focused on a single chosen parameter at a given time as the dominant indicator of future solar activity. Here, we used the amplitude of the previous cycle as a precursor. A significant positive correlation was found between the amplitudes of the odd-numbered and the next even-numbered cycles. The correlation coefficient was equal to 0.57 when the pair of cycles 7-8 was not taken into account. Using the obtained regression equation for maxima of odd-even cycles and the amplitude of the current Solar Cycle 25 (160.8 in October 2024), we estimated the strength of the next Solar Cycle 26. Solar Cycle 26 is predicted to have an amplitude of 142.2 ± 52.7. This means that it will be higher than Solar Cycle 24 but lower than Solar Cycle 25. Using the predicted amplitude of Solar Cycle 26 and the regression equation for maxima of even-odd cycles, we can also estimate the amplitude of Solar Cycle 27 to be equal to 188.4±67.4. Solar activity is expected to increase in the next decades, and there is no evidence of a grand solar minimum like the Dalton or Maunder minimum.
Keywords: : solar activity, solar cycle prediction, sunspot number
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