Spectral Resolution Effects on Solar Irradiance Calculations

For this study, we compared the spectral and integrated irradiance computed by high-resolution and moderate-resolution radiative transfer models (FASE and MODTRAN). It was found that the spectral resolution of a top of the atmosphere solar irradiance, coupled with the spectral resolution of the model used to compute the atmospheric transmittance, can influence the calculation of integrated solar irradiance. Further, differences between FASE and MODTRAN3.5 transmission calculations were identified, and the MODTRAN band model was upgraded, resulting in MODTRAN3.7.