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تسجيل مستخدم جديدSolar cycle activity: an early prediction for cycle #25
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Stefano Sello
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Solar activity forecasting is an important topic for numerous scientific and technological areas, such as space mission operations, electric power transmission lines, power transformation stations and earth geophysical and climatic impact. Nevertheless, the well-known difficulty is how to accurately predict, on the basis of various recorded solar activity indices, the complete evolution of future solar cycles, due to highly complex dynamical and stochastic processes involved, mainly related to interaction of different components of internal magnetic fields. There are two main distinct classes of solar cycle prediction methods: the precursor-like ones and the mathematical-numerical ones. The main characteristic of precursor techniques, both purely solar and geomagnetic, is their physical basis. Conversely, the non-precursor methods use different mathematical and/or numerical properties of the known temporal evolution of solar activity indices to extract useful information for predicting future activity. For current solar cycle #24 we obtained fairly good statistical performances from both precursor and purely numerical methods, such as the so-called solar precursor and nonlinear ones. To further check the performances of these prediction techniques, we compared the early predictions for the next solar cycle #25. Preliminary results support some coherence of the prediction methods considered and confirm the current trend of a relatively low solar activity.
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Solar activity cycle varies in amplitude. The last Cycle 24 is the weakest in the past century. Suns activity dominates Earths space environment. The frequency and intensity of the Suns activity are accordant with the solar cycle. Hence there are pra
ctical needs to know the amplitude of the upcoming Cycle 25. The dynamo-based solar cycle predictions not only provide predictions, but also offer an effective way to evaluate our understanding of the solar cycle. In this article we apply the method of the first successful dynamo-based prediction developed for Cycle 24 to the prediction of Cycle 25, so that we can verify whether the previous success is repeatable. The prediction shows that Cycle 25 would be about 10% stronger than Cycle 24 with an amplitude of 126 (international sunspot number version 2.0). The result suggests that Cycle 25 will not enter the Maunder-like grand solar minimum as suggested by some publications. Solar behavior in about four to five years will give a verdict whether the prediction method captures the key mechanism for solar cycle variability, which is assumed as the polar field around the cycle minimum in the model.
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