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Assessment of models proposed for the 1981 revision of the IGRF

N.W. Peddie·E.B. Fabiano
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Abstract

For the second revision of the International Geomagnetic Reference Field (IGRF), the U. S. National Aeronautics and Space Administration (NASA), the U. K. Institute of Geological Sciences (IGS), and the U. S. Geological Survey (USGS) submitted proposed models of the Earth's main magnetic field at 1965.0, 1970.0, 1975.0, and 1980.0, and its secular variation during 1980-1985. We assessed the proposed models by comparing them with annual mean values from worldwide magnetic observatories, data for 1978-1980 from 63 U. S. magnetic repeat stations, and rates-of-change values for worldwide magnetic observatories for 1965-1985 that were derived from straight lines fitted to annual means for five-year intervals. We also mutually compared the 1980 models.

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N.W. Peddie, E.B. Fabiano. 1982. Assessment of models proposed for the 1981 revision of the IGRF. https://doi.org/10.5636/jgg.34.387

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