Abstract
A numerical integration method for analyzing the geomagnetic field is developed from Poisson's integral. A new surface grid, suitable for use with integral analysis, is described. This grid is based on subdivisions of a spherical icosahedron, and its points are almost uniformly spaced over a sphere. This integration method is applied to calculations of field values, field lines, and conjugate points. The results are compared with those of earlier spherical-harmonic analyses by Vestine and Sibley. A comparison is also made between those conjugate points calculated by spherical harmonics from different sets of coefficients derived from various sets of isomagnetic charts.
