Open Access

Fig. 5.


Density of granules per Mm2 corrected for the pixel area. Dots correspond to individual measurements, and crosses show daily averages with estimated error bars. We recall that we selected one single day for each month of the observation period. Dates where spots (pores) are present in the field of view are indicated with red (blue) symbols. Variations of the 13-month smoothed monthly mean total sunspot number (SILSO World Data Center 2008-2019: International Sunspot Number Monthly Bulletin and online catalogue, are overplotted (solid line).

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.