Confirmation of the ‘‘Lost’’ Cycle and the Gnevyshev–Ohl Rule in a Series of Sunspot Areas Spanning 410 Years

Abstract

The Gnevyshev–Ohl rule is considered for a new series of sunspot areas on a four-century time scale (Nagovitsyn and Osipova 2021). The hypothesis of Usoskin et al. (2001) about the existence of an additional small cycle on the descending branch of Zürich cycle 4 is accepted. This leads to a change in the parity of the cycles earlier than 5. Eleven-year cycles in the 17th century have been distinguished. Their average duration, from minimum to minimum, is \(T=8.9\pm 1.4\) years. New data and approaches have led us to conclude that the Gnevyshev–Ohl rule holds for the 410-year interval as a whole without the exclusion of the pair of Zürich cycles 4 and 5 adopted in the rule previously.