The amount of evapotranspiration from a woodland largely depends on the site and stand productivity. The factor largely responsible for the stand productivity (productivity class) of an individual forest type under the climatic conditions of northwest Russia is temperature. If mean annual air temperature rises by 1°C and 2°C the average productivity of a coniferous stand in Karelia will increase by 0.3-0.4 and 0.6-0.8 of the productivity class, respectively. The average estimated increment of annual evapotranspiration from a forest in a sufficiently large catchment area will not exceed 15-20 mm even if the warming up is 2°C.