Using the EIGEN-GRACE02S gravity field to investigate defectiveness of marine gravity data

Abstract

The latest GRACE-only gravity field model, EIGEN-GRACE02S, is used to investigate if high resolution marine gravity data exhibit medium or long wavelength errors. The "trackiness" of the GRACE gravity field requires a rigorous smoothing down to about 4° block mean values or a harmonic degree at or below 40. The anomaly differences between GRACE and the marine gravity is found to be inconspicuous, transforms however to large scale pattern of geoid height differences with ± 0.4m amplitude, located differently for the marine data sets investigated.