Solar radiation over Turkey and its analysis

Ground-based solar-radiation observations have rather high random errors, which were sourced from maintenance, calibration and/or inaccurate instruments in Turkey. Satellite-based radiation data obtained from the National Aeronautics and Space Administration (NASA) were compared with reliable ground observations, and it was found that the global solar incident insolation data of the NASA Surface Meteorology and Solar Energy (SSE) dataset is usable, with a rather low mean relative error of about 4%. Therefore, monthly and annual spatial distribution over Turkey and solar-radiation time series were analysed in order to detect the potential of solar radiation and to find out variations and trends, respectively.