On the Principles and Prospects of Gravity Field Determination by Satellite Methods

Abstract

In preparation of the altimetric satellite missions Topex-Poseidon and ERS-1 a whole new generation of geopotential models was computed. The TEG-2 model of the University of Texas, GEM-Tl to GEM-T3 of NASA Goddard Space Flight Center and GRIM4-S1 and GRIM4-C1 of DGFI/GRGS. Characteristic to these fields is that all program parts were carefully evaluated and improved, more data to more satellites were included and a thorough error assessment took place. These models serve as current standard of satellite based gravity field modelling. On the other hand there exist concepts to further improve our current fields in terms of resolution and accuracy with a single dedicated gravity field satellite mission. Thus the question arises whether such an expectation is well-founded or, more general, where does geopotential modelling by satellites go to?