Gravity Gradients and Spherical Harmonics - a Need for Different Goce Products?

GOCE will deliver Level 2 products such as grids of geoid heights and gravity anomalies, along with a spherical harmonic model of the Earth’s gravity field. Furthermore, Level 1B calibrated gravity gradients will be available. The majority of these products may seem superfluous, as they are all linear functionals of one and the same quantity, the Earth’s gravitational potential. We will show why both observed gravity gradients and derived spherical harmonics might be useful. Their different information content will be discussed as well as the difficulties that occur when one product is to be transformed into another product.