Comparison of hourly and daily Penman-Monteith grass- and alfalfa-reference evapotranspiration equations and crop coefficients for maize under arid climatic conditions

The practical estimation of actual crop evapotranspiration (ETa) frequently involves calculating a reference crop evapotranspiration (ETref), and then applying suitable crop coefficients (Kc). Two standardized calculation procedures based on the Penman-Monteith equation are commonly used as ETref estimations (ETo for grass and ETr for alfalfa) across diverse environments. However, not much is known about the difference between ETo and ETr and …