Geomagnetic Potential in Offset-Dipole Coordinates

摘要

The geomagnetic potential (IGRF 1965.0) is converted into the spherical coordinates of an optimally offset and inclined dipole by means of a least-squares fit to the 'transformed' Schmidt coefficients. Time derivatives of the resulting spherical-harmonic expansion coefficients are obtained by taking symmetric first differences (1966.0 vs 1964.0). (Author)