Possible variations in sunspot groups before flaring activity during solar cycles 23 and 24

Abstract

We investigated the possible morphological variations observed in sunspot groups on the day before flaring activity occurred between January 1996 and November 2014. We found that 77% of all flaring sunspot groups were large and complex (D, E, and F modified Zurich classes). In addition, the Zurich classification of A, B, and C class sunspot groups changed more than 50%, while the remaining groups (D, E, F, and H) did not change considerably before the flare activity. Results showed that there was a remarkable increase in the sunspot areas of groups D, E, and F; in contrast, the sunspot areas of groups A, B, C, and H showed a decrease before the flaring 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 increase in the same period.