Calculated Snowpack Evaporation during Chinooks along the Eastern Slopes of the Rocky Mountains in Alberta

Abstract

Evaporation from the snowpack during chinooks results in significant moisture loss along the eastern slopes of the Rocky Mountains in Alberta. From January through March 1976, calculated potential evaporation was as high as 88 mm depth of water above tree line and 53 mm below tree line. Potential evaporation averaged 1.2 mm day?1 in 1975 and 2.0 mm day?1 in 1976. Snowpack evaporation was no greater at the two major gaps in the study area than where no gaps existed. Evaporation was greater above tree line than below tree line but was not a function of elevation. For the same 3-month period there were 24 chinook days in 1975 and 22 in 1976.