[IEEE IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Valencia, Spain (2018.7.22-2018.7.27)] IGARSS 2018 - 2018 IEEE International Geoscience and Remote Sensing Symposium - Comparative Validation of Clear Sky Irradiance Models over Finland

摘要： Accurate knowledge of the solar irradiance is required for various climate and energy applications. For these applications as well as irradiance forecasts, estimates of clear sky irradiance are often essential as basis for further calculations. In this paper we comparatively validate clear sky irradiance estimates from four fast clear sky models with varying atmospheric inputs. The comparison is made against in situ irradiance observations from five stations in southern Finland, for four summer months in 2016. The main atmospheric inputs, Aerosol Optical Depth and water vapour, are taken from MACC and ERA-Interim reanalysis datasets. Nearly all models underestimate irradiance in the used sites, with McClear, Pvlib Ineichen and Pvlib Solis with default input performing the best. The use of reanalysis inputs increase the Solis errors, which is considered to be because of the AOD and water vapour climatologies not representing the specific sites and times adequately.