Publication
Names
  • M. Dumont
  • O. Brissaud
  • G. Picard
  • B. Schmitt
  • J.-C. Gallet
  • Y. Arnaud
Title
High-accuracy measurements of snow Bidirectional Reflectance Distribution Function at visible and NIR wavelengths - comparison with modelling results
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.
Keywords
spectroscopy, bidirectional reflection, radiative transfer simulation, directional-hemispheric albedo spectra, anisotropy factor spectra, BRDF, visible, near-IR, snow, H2O, Earth
Content
sample, material-matter, spectral data, BRDF data, earth sciences
Year
2010
Journal
Atmospheric Chemistry and Physics
Volume
10
Number
5
Pages
2507 - 2520
Pages number
14
Document type
article
Publication state
published