A COMPARISON OF EVAPORATION FROM SNOW AND SOIL SURFACES

ABSTRACT

During the spring of 1961, evaporation from snow and soil surfaces was measured in the central Rocky Mountains near Fraser, Colorado. Measurements were made in natural forest openings at 9,000 feet elevation. Evaporation from wet soil surfaces greatly exceeded evaporation from nearby snow. There was little evidence of transfer of vapor from soil to nearby patches of snow, but as areas of bare, wet soil increased and evaporation amounts from such surfaces increased, evaporation from snow decreased. It was concluded that, as greater amounts of water evaporated from soils, the vapor pressure of the air was raised sufficiently to reduce evaporation from snow. Since transfer of vapor from soil to snow appeared small at best, evaporation losses from snow and soil surfaces essentially constituted a total moisture loss from the area.