Prediction of solar activity on the basis of spectral characteristics of sunspot number
- 1Instituto Nacional de Pesquisas Espaciais (INPE), Av. Astronautas, 1758 ZIP 12201-970, São José dos Campos, SP, Brazil
- 2Faculdade de Tecnologia Thereza Porto Marques (FAETEC) ZIP 12308-320, Jacareí, Brazil
Abstract. Prediction of solar activity strength for solar cycles 23 and 24 is performed on the basis of extrapolation of sunspot number spectral components. Sunspot number data during 1933-1996 periods (solar cycles 17-22) are searched for periodicities by iterative regression. The periods significant at the 95% confidence level were used in a sum of sine series to reconstruct sunspot series, to predict the strength of solar cycles 23 and 24. The maximum peak of solar cycles is adequately predicted (cycle 21: 158±13.2 against an observed peak of 155.4; cycle 22: 178<±13.2 against 157.6 observed). Solar cycle 23 was predicted to have a peak in 2000 with maximum amplitude of 125±13.2, in good agreement with the 119.6 observed. The minimum of solar cycle 23 is predicted to occur around 2007-2008. For solar cycle 24, the maximum is predicted to occur in 2012 (115±13.2) or 2013 (117±13.2) and this shall be a very weak solar cycle.