Validation of Satellite-derived Daily Sunshine Duration Estimates Against Campbell-Stokes Sensor Measurements in Côte d’Ivoire

Accurate measurement of sunshine duration (SDU) is crucial for various meteorological and solar energy applications. This study evaluates the accuracy of satellite-derived sunshine duration (SDU) data (Surface Radiation Data Set-Heliosat - Edition 3) against ground-based measurements from eight stations across Côte d’Ivoire. Key metrics include the correlation coefficient (R), root mean square deviation (RMSD), mean bias deviation (MBD), and scatter index (SI). The strongest correlations were found at San Pédro (R = 0.952) and Korhogo (R = 0.950), while the weakest was at Odienné (R = 0.839). RMSD ranged from 0.9 hours/day at Korhogo to 2.4 hours/day at Odienné, with general satellite overestimation. These results highlight variability in the satellite data’s accuracy, suggesting its reliability in some regions but calling for localized validation in others.