. Pfeifroth, abbreviated as CRS. These two latter data sets begin in 2004 and offer 15 min SSRD with the same resolution than the SEVIRI pixels, i.e. 3 km at nadir and degrading as the satellite viewing angle is increasing. Several works have compared the quality of HC3v5 and CRS and have reported a slightly better quality for HC3v5, see Trolliet et al. (2018) and its references. Trolliet et al. (2018) also performed a comparison between SARAH-2, CRS and HC3v5 for daily means of irradiance in the tropical Atlantic Ocean for the period 2012-2013 and reported fairly similar performances between the three data sets. It can thus be speculated that at the spatial resolution of 0.25°, the SSRD-H3E data set offers the same quality than the SARAH-2 data set for the period starting in 2004, and surpasses the CRS data set. One may not conclude for the previous periods but one may note that Pfeifroth, 2017.

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