Optimum use of satellite intensity and vector data in modelling the main geomagnetic field

Abstract

Monte Carlo simulation has been used to investigate the optimum use of Magsat-type intensity and vector data in producing spherical harmonic models of the main geomagnetic field. As is well known, using only intensity data gives large vector errors in the model field, particularly in the equatorial region. Adding (or substituting) quite small amounts of vector data in the equatorial region very much improves the model. Adding more vector data gives a bit more improvement, but polewards of about 30° latitude it is better to use good (small variance) intensity data rather than poor (large variance) vector data. By making better use of the existing data it should be possible to reduce the errors of the GSFC (12/83) model by a factor of about three. © 1987.