Determination of the Effective Accuracy of Satellite-derived Global, Direct and Diffuse Irradiance in the Central United States

Using high precision irradiance data from the Southern Great Plains ARM extended facility network [1], we confirm results of initial efforts by the authors to quantify the effective -intrinsic -accuracy of hourly global irradiances derived from geostationary satellite observations. We extend this initial analysis to other components –direct and diffuse – as well as other time steps – 1-minute and daily. For pixel sizes of the order of 10 km, we show that accuracy achievable with current satellite-based models is remarkably close to the pixel-wide achievable by a ground station located within the considered pixel.