Did predictions of the maximum sunspot number for solar cycle No. 22 come true?
Abstract
Solar cycle No. 22 which started in 1986 seems to have already passed through a maximum. The maximum annual mean sunspot number was 157 for 1989. The maximum twelvemonth running average was 159, centered on July 1989. For cycle 21, the similar value was 165 centered at December 1979. Thus, cycle 22 is slightly weaker than cycle 21. Schatten and Sofia (1987) had predicted a stronger cycle 22 (170 ± 25) as compared to cycle 21 (140 ± 20). Predictions based on single variable analysis, viz., R _{ z }(max) versus aa(min) were ∼ 165 and came true. Predictions based on a bivariate analysis, viz., R _{ z }(max) versus aa(min) and R _{ z }(min) were ∼ 130 and proved to be underestimates. Other techniques gave over or underestimates.
 Publication:

Solar Physics
 Pub Date:
 July 1992
 DOI:
 10.1007/BF00148437
 Bibcode:
 1992SoPh..140..171K
 Keywords:

 Prediction Analysis Techniques;
 Solar Cycles;
 Solar Terrestrial Interactions;
 Sunspots;
 Coronal Holes;
 Mathematical Models;
 Periodic Variations;
 Solar Activity Effects;
 Solar Physics