Thermal Regime of a Prairie Snowcover
1977
Granger, R. J. | Chanasyk, D. S. | Male, D. H. | Norum, D. I.
An energy budget approach was used to study the melting of a shallow prairie snowpack. In the analysis, all the terms of the energy budget were determined independently. The major source of energy for the melt was the net radiation flux. Over a continuous snowcover the contribution of sensible heat to the melt could not be represented by a simple low-level temperature index, but was dependent on the energy content of the air mass. The latent heat flux responded to the radiation flux, with daytime evaporation and nighttime condensation, however the net daily flux was evaporative. Nighttime refreezing of the snowpack limited the runoff, with approximately 40% of the daily meltwater being retained or refrozen in the snowpack. Beneath the melting snowcover the diurnal cycle of soil heat flux was almost completely eliminated. Monitoring of soil moisture changes during the melt period showed that very little infiltration occurred until the soil had thawed.
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