Atmospheric Chemistry and Physics www.atmos-chem-phys.net 1680-7316 1680-7324 10 5 2010 10.5194/acp-10-2507-2010 http://www.atmos-chem-phys.net/10/2507/2010/ http://www.atmos-chem-phys.net/10/2507/2010/acp-10-2507-2010.html http://www.atmos-chem-phys.net/10/2507/2010/acp-10-2507-2010.pdf 2507 2520 2010-03-11 High-accuracy measurements of snow Bidirectional Reflectance Distribution Function at visible and NIR wavelengths – comparison with modelling results M. Dumont mdumont@lgge.obs.ujf-grenoble.fr O. Brissaud G. Picard B. Schmitt J.-C. Gallet Y. Arnaud Laboratoire de Glaciologie et de Géophysique de l'Environnement, UMR 5183, 54 rue Molière, 38402 Saint Martin d'Hères cedex, France Laboratoire de Planétologie de Grenoble BP 53, 38401 Grenoble Cedex 9, France IRD-LTHE, Laboratoire de Glaciologie et de Géophysique de l'Environnement, 54 rue Molière, 38402 Saint Martin d'Hères cedex, France High-accuracy measurements of snow Bidirectional Reflectance Distribution Function (BRDF) were performed for four natural snow samples with a spectrogonio-radiometer in the 500–2600 nm wavelength range. These measurements are one of the first sets of direct snow BRDF values over a wide range of lighting and viewing geometry. They were compared to BRDF calculated with two optical models. Variations of the snow anisotropy factor with lighting geometry, wavelength and snow physical properties were investigated. 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