Synchronized Helicity Oscillations: A Link Between Planetary Tides and the Solar Cycle?
Recent years have seen an increased interest in the question of whether the gravitational action of planets could have an influence on the solar dynamo. Without discussing the observational validity of the claimed correlations, we examine which possible physical mechanism might link the weak planetary forces with solar dynamo action. We focus on the helicity oscillations that were recently found in simulations of the current-driven, kink-type Tayler instability, which is characterized by an \(m=1\) azimuthal dependence. We show how these helicity oscillations may be resonantly excited by some \(m=2\) perturbations that reflect a tidal oscillation. Specifically, we speculate that the tidal oscillation of 11.07 years induced by the Venus–Earth–Jupiter system may lead to a 1:1 resonant excitation of the oscillation of the \(\alpha\)-effect. Finally, we recover a 22.14-year cycle of the solar dynamo in the framework of a reduced zero-dimensional \(\alpha\)–\(\Omega\) dynamo model.
KeywordsSolar cycle Models helicity Theory
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