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The broadband albedo of surface snow is determined both by the near-surface  profile of the physical and chemical properties of the snowpack and by  the spectral and angular characteristics of the incident solar  radiation. Simultaneous measurements of the physical and chemical  properties of snow were carried out at Summit Camp, Greenland  (72°36´ N, 38°25´ W, 3210 m a.s.l.) in May  and June 2011, along with spectral albedo measurements. One of the  main objectives of the field campaign was to test our ability to  predict snow spectral albedo by comparing the measured albedo to the  albedo calculated with a radiative transfer model, using measured snow physical and chemical  properties. To achieve this goal, we made daily measurements of the snow spectral albedo in the  range 350–2200 nm and recorded snow stratigraphic information  down to roughly 80 cm. The snow specific surface area (SSA)  was measured using the DUFISSS instrument (DUal Frequency Integrating  Sphere for Snow SSA measurement, Gallet et al., 2009). Samples were  also collected for chemical analyses including black carbon (BC) and  dust, to evaluate the impact of light absorbing particulate  matter in snow. This is one of the most comprehensive albedo-related  data sets combining chemical analysis, snow physical properties and  spectral albedo measurements obtained in a polar environment. The  surface albedo was calculated from density, SSA, BC and dust profiles  using the DISORT model (DIScrete Ordinate Radiative Transfer, Stamnes et al., 1988) and  compared to the measured values. Results indicate that the energy absorbed by the  snowpack through the whole  spectrum considered can be inferred within 1.10%. This  accuracy is only slightly better than that which can be obtained  considering pure snow, meaning that the impact of impurities on the  snow albedo is small at Summit. In the near infrared, minor deviations in albedo up to 0.014  can be due to the accuracy of radiation and SSA measurements and to the surface  roughness, whereas deviations up to 0.05 can be explained by the spatial heterogeneity of  the snowpack at small scales, the assumption of spherical snow grains made for DISORT  simulations and the vertical resolution of measurements of surface layer physical properties.  At 1430 and around 1800 nm the discrepancies are larger and independent of the snow  properties; we propose that they are due to errors in the ice refractive index at these  wavelengths. This work contributes to the development of physically based albedo schemes  in detailed snowpack models, and to the improvement of retrieval  algorithms for estimating snow properties from remote sensing data

Snow spectral albedo at Summit, Greenland: measurements and numerical simulations based on physical and chemical properties of the snowpack