Some peculiarities in longitude distribution of sunspot groups over last four eleven-year solar cycles

This paper considers a longitude distribution of sunspot groups over 1982–2013, using data from the National Geophysical Data Center (Boulder, USA). The space-time distribution of sunspot groups is analyzed in coordinate sectors calculated from heliographic longitudes of the groups. A longitude extent of a coordinate sector is compared to the average size of one active region (30–40°). Then, in each coordinate sector, evolutionary activity of sunspot groups is summarized according to Malde classification indices throughout the observation period. The longitude distribution of large sunspot groups made in such a way does not reveal anticorrelation between Northern and Southern hemispheres in sunspot cycle 23.