ACPD Atmospheric Chemistry and Physics Discussions ACPD 1680-7375 Copernicus GmbH Göttingen, Germany 10.5194/acpd-7-17873-2007 Improving the solar zenith angle dependence of broadband UV radiometers calibration Cancillo M. L. 1 Serrano A. 1 Antón M. 1 García J. A. 1 Vilaplana J. M. 2 Departamento de Física, Universidad de Extremadura, 06071 Badajoz, Spain INTA Departamento de Observación de la Tierra, Teledetección y Atmósfera, ESAt, "El Arenosillo", Huelva, Spain 13 12 2007 7 6 17873 17892 This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. This article is available from http://www.atmos-chem-phys-discuss.net/7/17873/2007/acpd-7-17873-2007.html The full text article is available as a PDF file from http://www.atmos-chem-phys-discuss.net/7/17873/2007/acpd-7-17873-2007.pdf

This paper focusses on the proposal of a new method for the calibration of broadband ultraviolet radiometers. The advantage of the method proposed is the accurate modelling of the dependence on the solar zenith angle. The new model is compared with other one-step calibration methods and with the two-step method, which requires the knowledge of the actual response of the broadband radiometer. For this purpose, three broadband radiometers are calibrated against a spectrophotometer of reference. The new method is validated comparing its predictions with the spectrophotometer measurements using an independent data set.

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