Application of the Cross-Wavelet Transforms to Time Series of Solar Activity

摘要

Cross-wavelet transforms analysis is proposed to investigate the phase relationship between sunspot group numbers and sunspot numbers during the period of1874 May to 2010 December. Their phase relationship is not only time-dependent but also frequency-dependent, which implies that their phase asynchrony is not a simple linear relationship, although they are highly correlated with each other. This study shows that cross-wavelet transforms technique for the phase analysis between different time series of solar activity is fairly useful.