On the characteristics of successive geomagnetic jerks

Minh Le Huy (1, 2) , Mioara Alexandrescu (2) , Gauthier Hulot (2) , Jean-Louis Le Mouël (2)

1 Institute of Geophysics [Hanoi]
2 IPGP - Institut de Physique du Globe de Paris

Spherical harmonic models of the 1969, 1979 and 1992 geomagnetic jerks are computed using data from about 160 worldwide geomagnetic observatories. The dominance of the internal origin part with respect to the external one confirms again the internal origin of these events. A change of sign is observed between two successive jerks (1969–1979, 1979–1992). The acceleration jump of the fluid flow at the core mantle boundary (CMB) generating the three jerks is computed. Striking similarities between the three acceleration maps are observed (within the sign change mentioned above). These results suggest some long time scale memory in the processes that are responsible for the jerks. These processes remain to be elucidated

Domaines: Géophysique [physics.geo-ph]

Minh Le Huy, Mioara Alexandrescu, Gauthier Hulot, Jean-Louis Le Mouël. On the characteristics of successive geomagnetic jerks. Earth Planets and Space, 1998, 50, pp.723-732. ⟨10.1186/BF03352165⟩. ⟨insu-01409768⟩