Possible variations in sunspot groups before aring activity during solar cycles23 and 24

Abstract

We investigated the possible morphological variations observed in sunspot groups on the day before aringactivity occurred between January 1996 and November 2014. We found that 77% of all aring sunspot groups were largeand complex (D, E, and F modi ed Zurich classes). In addition, the Zurich classi cation of A, B, and C class sunspotgroups changed more than 50%, while the remaining groups (D, E, F, and H) did not change considerably before the areactivity. Results showed that there was a remarkable increase in the sunspot areas of groups D, E, and F; in contrast, thesunspot areas of groups A, B, C, and H showed a decrease before the aring activity during the examined time period.Finally, the sunspot counts of groups A, C, and H showed a decrease, while groups B, D, E, and F showed an increasein the same period.