Relationship between Ultraviolet-B Radiation and Broadband Solar Radiation under All Sky Conditions in Kuwait Hot Climate

In the present study, continuous measurements of solar global (G) and ultraviolet-B (UVB) radiation are taken in Kuwait for 2014–2019 all weather conditions. Hourly curves show a sinusoidal behavior both G UVB radiation. Statistical analysis indicates that there is good agreement between hourly as coefficients determination (R2) years larger than 0.91 root-mean-square error (RMSE) mean bias (MBE) very small. The percentage ratio (UVB/G) found to decrease with due cloudy sky addition, tends clearness index (KT), indicating higher can be obtained cloudier atmosphere. Another interesting finding KT (KTUVB) directly proportional, third-order polynomial fit gives an acceptable formula (R2 = 0.859). Daily values well correlated R2 close unity years. RMSE MBE from daily greatly enhanced almost zero. maximum 27.94 MJ/m2 0.0044 MJ/m2, respectively, occurring June 2015. Finally, excellent linear monthly equal negligible. Thus, predicted or empirical utilized high accuracy predict at locations where measured.