Residual phasor plot of the GPS-observed vertical displacement minus predicted OTL, for harmonic M₂, using the ocean tide model FES2014b replaced with the regional model CIAM2. The Green's functions are based on earth model STW105, including anelastic dispersion ‘ad’ effects, with the shear modulus values adjusted by −16 per cent (red arrow), −24 per cent (green arrow) and −35 per cent (blue arrow) for the layer at 24.4–220 km depth. Phases (positive) are given with respect to Greenwich.