Shaken and stirred: When Bond meets Suess-de Vries and Gnevyshev-Ohl

TL;DR

This paper proposes that the solar dynamo's prominent cycles and grand minima can be explained by double synchronization with planetary tidal forces and solar barycenter motion, leading to intermittent chaos and challenging long-term solar activity predictions.

Contribution

It introduces a novel model linking solar cycle features to planetary influences and demonstrates how this can produce observed solar variability and grand minima.

Findings

Grand minima emerge as intermittent events in simulations.

Solar cycles are synchronized with planetary motions.

Long-term prediction of solar activity remains challenging.

Abstract

We argue that the most prominent temporal features of the solar dynamo, in particular the Hale cycle, the Suess-de Vries cycle (associated with variations of the Gnevyshev-Ohl rule), Gleissberg-type cycles, and grand minima can be self-consistently explained by double synchronization with the 11.07-years periodic tidal forcing of the Venus-Earth-Jupiter system and the (mainly) 19.86-years periodic motion of the Sun around the barycenter of the solar system. In our numerical simulation, grand minima, and clusters thereof, emerge as intermittent and non-periodic events on millennial time scales, very similar to the series of Bond events which were observed throughout the Holocene and the last glacial period. If confirmed, such an intermittent transition to chaos would prevent any long-term prediction of solar activity, notwithstanding the fact that the shorter-term Hale and Suess-de Vries cycles are clocked by planetary motion.