GRIDDED AEROSOL OPTICAL DEPTH CLIMATOLOGICAL DATASETS OVER CONTINENTS FOR SOLAR RADIATION MODELING

A methodology for the development of gridded datasets of aerosol optical depth (AOD) over continents is presented. This study focuses on the AOD at 550 nm and the Angstrom turbidity coefficients α and s determined from spectral data, e.g., by sunphotometers. A method to derive the broadband AOD from the air mass, α and s, is proposed. Different satellite-based datasets (AVHRR, MISR and MODISGOCART) are used to develop monthly-average AOD relative to their respective grid resolution. Corrections are made in regions were incorrect or missing AOD values are found. Moreover, a special interpolation/resampling technique is used to generate broadband AOD maps at a final resolution of 0.1x0.1° (about 10 km x 10 km), taking into account the altitude effect on AOD. The resulting maps are being used to predict irradiance over Africa, America and Asia, with the appropriate solar radiation models.