Structure function as a tool in AE and Dst time series analysis

Abstract

A new method to analyse the structure function (SF) has been constructed and used in the analysis of the AE time series for the years 1978–85 and Dst time series for 1957–84. It is shown that this SF analysis makes a clear distinction between affine and periodicity dominated time series, and it displays the essential periodicities of the series in a range relevant to its characteristic time scale. The AE time series is found to be affine such that the scaling exponent changes at a time scale of 113 (±9) minutes. On the other hand, in the SF function analysis, the Dst data are dominated by the 24‐hour and 27‐day periods. The 27‐day period is modulated by the annual variation.