Free Access

Fig. 3

thumbnail

Radial component of the surface magnetic field for the reference case. The upper panel shows a time-latitude diagram. The lower panel gives the polar fields, defined as the average radial field strength beyond ± 70° latitude (black curve) and the sunspot numbers (red curve). The vertical line indicates the time until which RGO sunspot group area data are available. The correlation coefficient of the maxima of the polar fields and the subsequent maxima of sunspot number for cycles 15 to 21 is 0.85.

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.