Phase relationship between polar faculae and sunspot numbers revisited: Wavelet transform analyses

Cross-correlation analysis and wavelet transform methods are proposed to investigate the phase relationship between the polar faculae (PF) and the sunspot numbers (SNs). It was found that: (1) the PF begin 52 months earlier than the SNs on the average of the considered time interval, which should lead to phase asynchrony between them; (2) the length of the Schwabe cycle for the PF obviously differ...