Value

Meaning

Air Temperature

Assumed to equal air temperature except when snow occurs on the soil.

f(PM-equation)

Estimated from the surface sensible heat flux, which is calculated as the residual of the surface energy balance using the soil evaporation rate as calculated by the P-M equation. The switch “Evaporation Method” must be set to either “PM-Eq, (1Par)”, “PM-Eq., (3Par)” or “K-function” to be able to use this option.

f(E-balance Solution)

Iterative numerical solution also used for estimating the soil evaporation and vapour pressure at the soil surface. The switch “Evaporation Method” must be set to “Iterative Energy Balance” to be able to use this option.