Fig. 10
From: Geomagnetic secular variation violating the frozen-flux condition at the core surface
The eastward component of the input SV (black solid curve) and (a) the non-advective SVs and (b) the non-geostrophic SVs from CM4 (1960.0–2002.0) at NGK. The non-advective and non-geostrophic SVs are computed with the truncation degrees LMF = 8 (light gray curve), 13 (dark gray curve), and 18 (dashed, dotted and dot-dashed curves). For LMF = 18, three results are plotted in accordance with different sets of the synthetic coefficients 
and 
(14 = l = 18) generated using Eqs. (13) and (14), with phase parameters 
selected three times randomly.