Using spectral analysis to detect singular events such as jerks in the geomagnetic field time series

Abstract. In this study we have applied two spectral techniques in terms of Fourier and wavelet analysis to geomagnetic field time series and compared the results with those obtained from analogous analyses to synthetic data. Then, an algorithm has been proposed to detect the geomagnetic jerks in time series, mainly being considered by the Eastern component secular variation. Applying such analysis to time series generated from global models has allowed us to depict the most important space-time features of the geomagnetic jerks on global scale, since the beginning of XXth century. Finally, a spherical harmonic analysis of the secular acceleration power spectrum has been computed since 1960 to 2000, bringing new insights in understanding these rapid changes of the geomagnetic field and their origin.