A Global Product of Weekly Forecast Reference Evapotranspiration for Water Stress Evaluation

A precise and spatialized estimation of environmental demand is necessary for agriculture's best use of water resources since, in conjunction with crop coefficient maps (Kc), it enables crop irrigation requirements to be determined. In this way, the National Center for Environmental Prediction (NCEP) global weather prediction system (GFS) enables estimation of the environmental demand or reference evapotranspiration (ET
o
) based on forecasts of the meteorological variables used in its calculation. Though its comparison with measurements reveals an overestimation mostly because of the spatial resolution of the model, the global model examined in this work exhibits a strong fit with the model supplied by the Spanish State Meteorological Agency (AEMET).