Phase asynchrony of the north-south sunspot activity

Aims.Northern and Southern sunspot activities demonstrate striking synchronous behavior during a solar cycle. But sometimes synchronization fails and the north-south asymmetry occurs. The problem is the origin of the north-south asymmetry and its quasi-regular oscillations.Methods.We employed Cross-Recurrence Plot analysis to extract synchronization between the Northern and Southern sunspot activities.Results.By using Cross-Recurrence Plot technique and extracting line of synchronization we found that the north-south sunspot asymmetry is due to phase asynchrony between Northern and Southern hemispheric activities.