The direct topographical correction in gravimetric geoid determination by the Stokes–Helmert method

Abstract.

 The direct topographical correction is composed of both local effects and long-wavelength contributions. This implies that the classical integral formula for determining the direct effect may have some numerical problems in representing these different signals. On the other hand, a representation by a set of harmonic coefficients of the topography to, say, degree and order 360 will omit significant short-wavelength signals. A new formula is derived by combining the classical formula and a set of spherical harmonics. Finally, the results of this solution are compared with the Moritz topographical correction in a test area.