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Main field and recent secular variation.

L.R. Alldredge
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Abstract

As Cain (1979) indicated might happen in the last IUGG quadrennial report, added resources were made available during the past few years and a real impulse was added to the geomagnetic work in the US by the launching of the MAGSAT Satellite. This new effort paid off in terms of new charts, additional long wavelength studies, and external source studies. As before, however, the future funding for new starts in geomagnetism does not look bright at the present time. A single MAGSAT in orbit a little more than seven months did wonders for main field (M.F.) charting, but did little or nothing for secular variation (S.V.) charting. It would take a number of repeated MAGSATS to help the S.V. picture. Meanwhile, the world magnetic observatory net and surface repeat stations remain as the main source of S.V. data. -from Author

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L.R. Alldredge. 2010-06-14. Main field and recent secular variation.. https://doi.org/10.1029/rg021i003p00599

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