The Food and Agricultural Organization (FAO) method for potential evapotranspiration assessment is based on the crop coefficient, which allows one to relate the reference evapotranspiration of well irrigated grass to the potential evapotranspiration of specific crops. The method was originally developed for cultivated species based on lysimeter measurements of potential evapotranspiration. Not ...

This study compares four different potential evapotranspiration equations according to Priestley Taylor, Kimberly Penman, Penman Monteith (FAO-56) and Hargreaves on a global basis to demonstrate their difference, and assess their impact on the calculation of stream flows. The various equations of potential evapotranspiration show great differences in magnitude. But due to the limited availabili...

for the purposed water resources management, irrigation scheduling, water usage optimization and gaining maximum yield two step fao method was applied to determine the water requirement (evapotranspiration) of sugar beet.  in this paper reference evapotranspiration were computed from recorded meteorological data at 38 weather stations using the hargreaves-samani method; and then through applyin...

In this study, yield-water and profit function was used to obtain water demand function in agriculture sector. The results showed that the ratio of actual to potential Evapotranspiration had positive, significant effecton the ratio of actual to potential yield for wheat and barley. Also, square ratio of actual to potential Evapotranspiration had negative, significant relationship. After estimat...

in this study, yield-water and profit function was used to obtain water demand function in agriculture sector. the results showed that the ratio of actual to potential evapotranspiration had positive, significant effecton the ratio of actual to potential yield for wheat and barley. also, square ratio of actual to potential evapotranspiration had negative, significant relationship. after estimat...

The evapotranspiration rate has a vital role in agricultural water management. In this paper, ability of Box-Jenkins models in forecasting the reference potential evapotranspiration is estimated. For this purpose meteorological data of Mehrabad synoptic station in Tehran was selected. Using this data and according to eight famous evapotranspiration equations amounts of evapotranspiration were f...

The actual evapotranspiration and runoff trends of five major basins in China from 1956 to 2000 are investigated by combining the Budyko hypothesis and a stochastic soil moisture model. Based on the equations of Choudhury and Porporato, the actual evapotranspiration trends and the runoff trends are attributed to changes in precipitation, potential evapotranspiration, rainfall depth and water st...