Journal of Glaciology
Snow grain-size characterization, its vertical and temporal evolution is a key parameter for the improvement and validation of snow and radiative transfer models (optical and microwave) as well as for remote-sensing retrieval methods. We describe two optical methods, one active and one passive shortwave infrared, for field determination of the specific surface area (SSA) of snow grains. We present a new shortwave infrared (SWIR) camera approach. This new method is compared with a SWIR laser- based system measuring snow albedo with an integrating sphere (InfraRed Integrating Sphere (IRIS)). Good accuracy (10%) and reproducibility in SSA measurements are obtained using the IRIS system on snow samples having densities greater than 200 kg m-3, validated against X-ray microtomography measurements. The SWIRcam approach shows improved sensitivity to snow SSA when compared to a near-infrared camera, giving a better contrast of the snow stratigraphy in a snow pit.
Montpetit, B.; Royer, A.; Langlois, A.; Cliche, P.; Roy, A.; Champollion, N.; Picard, G.; Domine, F.; and Obbard, R., "New Shortwave Infrared Albedo Measurements for Snow Specific Surface Area Retrieval" (2012). Open Dartmouth: Faculty Open Access Articles. 1757.