Green’s function for the magnetic inclination with respect to the Gauss coefficients (top-left panel) compared to their theoretical expectation. On the horizontal axis, the Gauss coefficients are grouped according to their degree l and ordered as: $g_l^0,g_l^1,h_l^1\dots g_l^l,h_l^l$. In the top-right panel, we show the same values reported in (a) in matrix form. Green’s function for the magnetic inclination with respect to the radial magnetic field at the CMB is shown in the bottom-left, showing our numerical result, and in the bottom-right panel, showing the result obtained using the analytical formulae reported in Johnson & Constable (1997). The illustrated solutions are calculated for Leeds, with latitude λ = 53.81° North and longitude ϕ = 1.549° West.