The Uncertainties of the Topographical Density Variations in View of a Sub-Centimetre Geoid

Abstract

We estimate the uncertainty of the modelled geoid heights based on the standard deviations of the topographic mass density variation. We model the geoid using the one-step integration method considering mass density variations along with their associated error estimates to calculate the direct and indirect topographic density effects on the geoid heights in the Helmert space. We employ the UNB_TopoDensT_2v01 global lateral density model and its standard deviations and test our algorithms in the Auvergne test area, in central France. Our results show that the topographic mass density variations are currently known well enough to model the geoid with sub-centimetre internal error in topographically mild regions such as Auvergne.