Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 8 6 2008 10.5194/acpd-8-19989-2008 http://www.atmos-chem-phys-discuss.net/8/19989/2008/ http://www.atmos-chem-phys-discuss.net/8/19989/2008/acpd-8-19989-2008.html http://www.atmos-chem-phys-discuss.net/8/19989/2008/acpd-8-19989-2008.pdf 19989 20018 2008-11-28 Calibrated sky imager for aerosol optical properties determination A. Cazorla J. E. Shields M. E. Karr A. Burden F. J. Olmo L. Alados-Arboledas alados@ugr.es Departamento de Física Aplicada, Facultad de Ciencias, Universidad de Granada, Fuentenueva s/n, 18071, Granada, Spain Centro Andaluz de Medio Ambiente (CEAMA), Junta de Andalucía-Universidad de Granada, Avda. del Mediterraneo s/n. 18071, Granada, Spain Marine Physical Lab, Scripps Institution of Oceanography, University of California San Diego, 9500 Gilman Dr., La Jolla CA 92093-0701, USA The calibrated ground-based sky imager developed in the Marine Physical Laboratory, the Whole Sky Imager (WSI), has been tested to determine optical properties of the atmospheric aerosol. Different neural network-based models calculate the aerosol optical depth (AOD) for three wavelengths using the radiance extracted from the principal plane of sky images from the WSI as input parameters. The models use data from a CIMEL CE318 photometer for training and validation and the wavelengths used correspond to the closest wavelengths in both instruments. 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