The latitude of filament bands at the sunspot minimum and the activity level in the two following 11-year solar cycles

Abstract

The zonal structure of the distribution of filaments is considered. The mean latitudes of two filament bands are calculated in each solar hemisphere at the minima of the sunspot cycle in the period 1924–1986: middle latitude φ _{2, m} and low latitude φ _{1, m} . It is shown that the mean latitude of the filament band φ _{2, m} at the minimum -m of the cycle correlates, with ϱ = 0.94, with the maximum - M sunspot area S(M) and maximum Wolf number W(M) in the succeeding solar cycle M. It is shown that the mean latitude of the low-latitude filament band φ _{1, m} is linearly dependent on the mean latitude filament band φ _{2, m + 1} at the succeeding minimum. We found a correlation of the latitude of the low-latitude filament band φ _{1, m} with the maximum sunspot area in the M + 1 cycle. This enables us to predict the power of two succeeding 11-year solar cycles on the basis of the latitude of filament bands at the minimum of activity, 1985–1986: W(22) ∼- 205 ± 10, W(23) ∼- 210 ± 10. The importance of the relationships found for theory and applied aspects is emphasized. An attempt is made to interpret the relationships physically.