Table 4 Probabilities of a sunspot group with area \(\ge\) 6000 MSH for next 30-, 50-, and 100-year periods for 80-, 100-, 120-, and 138-year data sets in the DHO and MA20 catalogues
From: Extremely large flares/multiple large flares expected from sunspot groups with large area
Data length | Occurrence probability of sunspot area \(\ge\) 6000 MSH calculated using the DHO catalog | Occurrence probability of sunspot area \(\ge\) 6000 MSH calculated using the MA30 catalog | ||||
|---|---|---|---|---|---|---|
30 years | 50 years | 100 years | 30 years | 50 years | 100 years | |
80 years (1879–1958) | 0.89 | 0.97 | 1.00 | 0.89 | 0.97 | 1.00 |
100 years (1879–1978) | 0.82 | 0.94 | 1.00 | 0.82 | 0.94 | 1.00 |
120 years (1879–1998) | 0.66 | 0.84 | 0.97 | 0.75 | 0.90 | 0.99 |
138 years (1879–2016) | 0.62 | 0.80 | 0.96 | 0.72 | 0.88 | 0.99 |