From Watts Up With That?

By Andy May

Dr. Frank Stefani and colleagues from Helmholtz-Zentrum Dresden – Rossendorf and the Institute for Numerical Modelling, University of Latvia, have proposed a new physically consistent model of solar variability. It proposes that the known solar cycles, from the eleven-year Schwabe cycle to the 193-year De Vries cycle are related to planetary orbits and the 19.86-year solar oscillation around the solar system barycenter.

The paper, “Rieger, Schwabe, Suess-de Vries: The Sunny Beats of Resonance,” explains the details of the concept. The press release, which is easier to read, explains the implications.

Astronomers and physicists have long been writing about the possible solar tidal effects of the planets, see Scafetta and Bianchini’s review paper here. The planetary orbits must affect the solar plasma in some fashion and the orbital patterns do correlate to proposed solar and climate cycles. While the statistical correlation was good, the underlying physics of why it all worked remained elusive.

Stefani and his colleagues have created a physically consistent model of the 193-year De Vries solar and climate cycle, the longest solar cycle physically modeled to date. There are longer solar cycles, such as the famous ~2450-year Bray cycle and the ~1,000-year Eddy Cycle, that have been observed but not modeled as precisely yet. This is an important start.

Stefani, F., Horstmann, G.M., Klevs, M. et al. Rieger, Schwabe, Suess-de Vries: The Sunny Beats of Resonance. Sol Phys 299, 51 (2024). https://doi.org/10.1007/s11207-024-02295-x (link)