North-south differences of solar cycles

TL;DR

This study identifies long-term north-south asymmetries in solar activity cycles, revealing phase differences that alternate over multiple Schwabe cycles and may relate to the Gleissberg cycle, with implications for understanding solar dynamics.

Contribution

It uncovers long-term variability in hemispheric phase differences of solar cycles and suggests potential links to the Gleissberg cycle, using two distinct analytical methods.

Findings

Hemispheric phase differences alternate every four Schwabe cycles.

Sunspot group tilt variations mirror hemispheric phase lags.

Long-term variability may be connected to the Gleissberg cycle.

Abstract

A long-term variation is detected in the north-south differences of the solar activity, the phase difference of hemispheric cycles alternates by four Schwabe cycles. This variability is demonstrated by two different methods. It can be the related to the Gleissberg cycle. The variation of the sunspot group tilts is similar to the hemispheric phase lags on a shorter timescale. Some possible relations are mentioned.