Multi-timescale Solar Cycles and the Possible Implications

TL;DR

This paper analyzes historical sunspot data to confirm multiple solar cycles, extrapolates future cycles, and examines the relationship between solar activity and flare occurrences, providing insights into solar cycle patterns and their implications.

Contribution

It identifies and confirms three types of solar cycles from historical data and predicts the characteristics of upcoming cycles, offering new insights into solar activity patterns.

Findings

Confirmation of 11-year, 103-year, and 51.5-year solar cycles.

Prediction of a long, weak Solar Cycle 24 around 2012-2014.

Flares tend to occur later in the Schwabe cycle, especially in its decay phase.

Abstract

Based on analysis of the annual averaged relative sunspot number (ASN) during 1700 -- 2009, 3 kinds of solar cycles are confirmed: the well-known 11-yr cycle (Schwabe cycle), 103-yr secular cycle (numbered as G1, G2, G3, and G4, respectively since 1700); and 51.5-yr Cycle. From similarities, an extrapolation of forthcoming solar cycles is made, and found that the solar cycle 24 will be a relative long and weak Schwabe cycle, which may reach to its apex around 2012-2014 in the vale between G3 and G4. Additionally, most Schwabe cycles are asymmetric with rapidly rising-phases and slowly decay-phases. The comparisons between ASN and the annual flare numbers with different GOES classes (C-class, M-class, X-class, and super-flare, here super-flare is defined as $\geq$ X10.0) and the annal averaged radio flux at frequency of 2.84 GHz indicate that solar flares have a tendency: the more powerful of the flare, the later it takes place after the onset of the Schwabe cycle, and most powerful flares take place in the decay phase of Schwabe cycle. Some discussions on the origin of solar cycles are presented.