The irregular variations of the external geomagnetic field from Intermagnet data

Details The irregular variations of the external geomagnetic field from Intermagnet data The irregular variations of the external geomagnetic field from Intermagnet data

Apr 2003

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2003ep%26s...55..173b&link_type=abstract

Earth, Planets and Space, Volume 55, p. 173-181.

Computer Science

Scientific paper

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.