• 责任者：Bai Chunhua (Beijing National Observatory of Space Environment ; Institute of Geology and Geophysics ; Chinese Academy of Sciences ; Beijing 100029 ; China) ; Xu Wenyao
• 刊名：Chinese Journal of Geophysics
• 出版年：2010
• 卷期：53(4)
• 关键词：地磁场长期变化 ; secular variations of geomagnetic field
• 页码：p.904-911
• 图表：6 illus., 43 refs.
• 分类号：0400
• issnNo：ISSN0001-5733
• isbnNo：CN11-2074/P

In this paper, the technique of wavelet transform is applied to analyze the gufm1 models during 1590~1990 A.D., for detecting the periodicities in the secular variations of the main geomagnetic field. The analysis suggests that there are three principal periodic components in the total Pole-strength of B field: a stable 30-year periodic component which is mainly seen in the equatorial component g¹₁ of the dipole field, and it is also generally seen in the non-dipole field; second, a dispersive quasi 50-year periodic component, typically contributed by the axial component of the dipole field g⁰₁, and the quadrupole also has a definite contribution; the last one is an intensity varying 110-year periodic component on centennial time scale, which seems to be from the equatorial component of the dipole field, and the octupole field also has a contribution.