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The irregular variations of the external geomagnetic field from Intermagnet data
Earth, Planets and Space volume 55, pages 173–181 (2003)
Abstract
The Intermagnet program publishes each year a cd-rom containing homogeneous series from a number of magnetic observatories (76 in 1999). These series are definitive one-minute values of the three components of the geomagnetic field. We transform these series using a simple nonlinear analysis tool able to characterize the activity of a signal, and we obtain a remarkably simple activity field, whose space and time variables separate over a large part of the Earth. The time function is almost identical for all observatories, and might be interpreted as an activity index. The—almost stationary—field geometry exhibits a dipole-like structure everywhere except in high latitudes.
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Bellanger, E., Anad, F., Le Mouël, JL. et al. The irregular variations of the external geomagnetic field from Intermagnet data. Earth Planet Sp 55, 173–181 (2003). https://doi.org/10.1186/BF03351746
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DOI: https://doi.org/10.1186/BF03351746