Evaporation at a High Arctic Site

Recent studies have demonstrated empirical relationships between surface soil moisture and the α′ parameter in Priestley and Taylor's version of the combination model. An evaporation study conducted at a high arctic site shows that for gravel and loamy surfaces underlain by permafrost, α′ can be expressed as the following function of soil moisture (Sm): α′ = 1.26/[exp (5.24 − 21.56 Sm) + 1] Comparison with α′ and soil moisture relationships obtained in more temperate latitudes suggests that under drying conditions the evaporation rate will be a response to the particular site characteristics, so that there is no unique relationship between surface soil moisture and evaporation rates.