Phase relationship between polar faculae and sunspot numbers

Deng Lin-hua, Yunnan Astronomical Observatory, Chinse Academy of Sciences.

Abstract
Linear and nonlinear approaches are used to investigate the phase asynchrony of the monthly numbers of polar faculae and sunspot numbers during the period of 1951 August to 1998 December. It is found that, (1) the monthly numbers of the polar faculae show leads of 52 months relative to that of the sunspot numbers, which should lead to phase asynchrony between them; (2) the Schwabe period length for the polar faculae obviously differs from that for the sunspot numbers, which should also lead to phase asynchrony between them; (3) both the cross-wavelet transform and wavelet coherence analyses show strong phase asynchronous behaviour of the two time series in the low-frequency and high-frequency components.