Fig. 5
From: Reducing filter effects in GRACE-derived polar motion excitations
Differences of the polar motion excitation functions derived from simulated noisy GRACE gravity field solutions by applying (1) only the DDK filter (green), (2) the DDK filter and the gain factors \(k^\text{org}\) (blue), (3) the DDK filter and the gain factors k (black), (4) the DDK filter, the gain factors k and the scaling factors \(f^i\) (red) with respect to the effective angular momentum functions derived from the true GRACE gravity field solutions for the continental hydrosphere \(\chi ^\text{H}\), oceans \(\chi ^\text{O}\), Antarctica \(\chi ^\text{A}\) and Greenland \(\chi ^\text{G}\)