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arXiv · 2007.14779

Shape of solar cycles and mid-term solar activity oscillations

D. D. Sokoloff·A. S. Shibalova·V. N. Obridko·V. V. Pipin
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Abstract

The evolution of the solar activity comprises, apart from the well-known 11-year cycle, various temporal scales ranging from months up to the secondary cycles known as mid-term oscillations. Its nature deserves a physical explanation. In this work, we consider the 5-to-6 year oscillations as derived both from sunspot and from solar magnetic dipole time series. Using the solar dynamo model, we deduced that these variations may be a manifestation of the dynamo nonlinearities and non-harmonic shape of the solar activity cycles. We conclude that the observed mid-term oscillations are related to the nonlinear saturation of the dynamo processes in the solar interior.

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D. D. Sokoloff, A. S. Shibalova, V. N. Obridko, V. V. Pipin. 2020-08-01. Shape of solar cycles and mid-term solar activity oscillations. https://doi.org/10.1093/mnras%2Fstaa2279

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