EVAPOTRANSPIRATION FROM ALFALFA AS RELATED TO EVAPORATION AND OTHER METEOROLOGICAL VARIABLES

Abstract

Evapotranspiration from irrigated alfalfa was related to evaporation from a Class A evaporation pan, an Experimental Farms buried tank, and a Bellani plate atmometer in addition to the meteorological variables temperature, sunshine, wind, and vapor pressure. Except for the evapotranspiration–wind relationship all simple correlation coefficients were significant when the crop was growing vigorously and completely shaded the ground.Although wind alone did not correlate significantly with either evaporation or evapotranspiration, it contributed appreciably when considered in combination with other meteorological variables. The limitations of simple correlation must be recognized in developing formulas intended for estimating evapotranspiration from meteorological data.