Title High-accuracy measurements of snow bidirectional reflectance distribution function at visible and NIR wavelengths; comparison with modelling results
Author Dumont, M.; Brissaud, O.; Picard, G.; Schmitt, B.; Gallet, J.C.; Arnaud, Y.
Author Affil Dumont, M., Laboratoire de Glaciologie et de Géophysique de l'Environnement, Saint Martin d'Heres, France. Other: Laboratoire de Planétologie de Grenoble, France; IRD, Laboratoire de Glaciologie et de Geophysique de l'Environnement, France
Source Atmospheric Chemistry and Physics, 10(5), p.2507-2520, . Publisher: Copernicus, Katlenburg-Lindau, International. ISSN: 1680- 7316
Publication Date 2010
Notes In English. Includes supplement, http://www.atmos-chem- phys.net/10/2507/2010/acp-10-2507-2010- supplement. pdf; published in Atmospheric Chemistry and Physics Discussions: 16 September 2009, http://www.atmos-chem-phys- discuss.net/9/19279/2009/acpd-9-19279- 2009.html ; accessed in May, 2011. 31 refs. GeoRef Acc. No: 310087
Index Terms absorption; accuracy; albedo; anisotropy; crystals; freezing; grain size; ice; ice crystals; models; physical properties; reflectivity; remote sensing; snow; solar radiation; France--Isere; Alps-- Mont Blanc; Alps; bidirectional reflectance distribution function; Chartreuse Mountains; Europe; France; geometry; intensity; Isere France; Mont Blanc; reflectance; shape analysis; spatial variations; wavelength; Western Alps; Western Europe
Abstract 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. Results show that at wavelengths with small penetration depth, scattering mainly occurs in the very top layers and the anisotropy factor is controlled by the phase function. In this condition, forward scattering peak or double scattering peak is observed. In contrast at shorter wavelengths, the penetration of the radiation is much deeper and the number of scattering events increases. The anisotropy factor is thus nearly constant and decreases at grazing observation angles. The whole dataset is available on demand from the corresponding author.
URL http://www.atmos-chem-phys.net/10/2507/2010/acp-10-2507-2010.pdf
Publication Type journal article
Record ID 65006766