Abstract
A method for the solution of Poisson's equation on the surface of a sphere is given. The method makes use of truncated double Fourier series expansions on the sphere and invokes the Galerkin approximation. It has an operation count of approximately I2J2(1 + log2J) for a latitude-longitude grid containing 2J(J − 1) + 2 data points. Numerical results are presented to demonstrate the method's accuracy and efficiency.