SNOW DEPTH REQUIRED FOR NEAR STEADY-STATE SOIL TEMPERATURES

The insulating value of snow was determined from 16 winters of measurements of snow depths, air temperatures and 1 cm soil temperatures in a soil frozen at least 5 cm deep. Data were aggregated into 2.5 cm snow depth categories and linear regression equations were calculated for the air temperature versus the 1 cm soil temperature for each 2.5 cm snow depth category. Five methods of analyzing the data were used to estimate the snow depth required for near steady-state soil temperatures. Depths ranging between 15 and 42.5 cm were indicated by the five methods as being necessary. The depth of snow found in this study for an essentially steady-state soil temperature is deeper than that found by the majority of investigators. This is believed to be the result of: (a) the shallower depth of the soil temperature sensor; (b) the larger number of samples that represented a more varied sampling in terms of snow densities; (c) a greater duration of the measurement periods.