Expected improvements to regional gravity field determination from the GRACE, CHAMP and GOCE satellite missions

Abstract

The current and planned dedicated satellite gravity field missions (i.e., GRACE, CHAMP and GOCE) will make significant improvements to long-wavelength global models of the Earth?s gravitational field. Used together, they will provide a more homogeneous, accurate and near-complete spatial coverage than was ever-achievable using `classical' techniques. GRACE and CHAMP will also measure temporal variations in the gravitational field. These data will offer considerably improved constraints on global and regional geophysical models, and the time varying components will offer a totally new dataset on contemporary geodynamic processes. This paper describes the concepts of dedicated satellite gravimetry and summarises the GRACE, CHAMP and GOCE mission parameters. Using published syntheses of the error degree variances of these new data, attempts will be made to quantify the level of improvement offered. This will then give an indication of how much more weight can be placed on these new data in geo-physical studies. Finally, a strategy will be proposed to integrate these new data with terrestrial gravimetry using spherical harmonic filters.