Table 1: Amplitude and phase of seasonal variations estimated from geodetic residuals (G-A-O), GRACE, CPC, and GLDAS-based excitations. For the annual variations, we note that GRACE-based excitation reach a better agreement in amplitude with geodetic residuals than the models.a

AnnualSemiannual
Amplitude Phase Amplitude Phase
mas degree mas degree

G-A-O
CPC
GLDAS
GRACE

G-A-O
CPC
GLDAS
GRACE

aThe reference date for the phase is 2004 January 1, 0h UTC.