Comparison between compactly-supported spherical radial basis functions and interpolating moving least squares meshless interpolants for gravity data interpolation in geodesy and geophysics

Abstract: The present paper is focused on the comparison of the efficiency of two important meshless interpolants for gravity acceleration interpolation. Compactly-supported spherical radial basis functions and interpolating moving least squares are used to interpolate actual gravity accelerations in southern Africa. Interpolated values are compared with actual values, gathered by observation. A thorough analysis is presented for the standard deviation of the differences between interpolated and actual values. Three different class of spherical radial basis functions-Poisson, singularity, and logarithmic-and four different type of basis functions for interpolating moving least squares approach-planar, quadratic, cubic, and spherical harmonics-are used. It is shown that in this particular problem compactly-supported spherical radial basis functions are faster and capable of achieving higher accuracies, compared to interpolating moving least squares scheme.