A New Simpler Method to Calculate Evapotranspiration

The purpose of this study was to evaluate the Hangreaves – Samani method for estimating evapotranspiration (ET) which utilizes readily available weather data and compare the results of this method to the Priestly – Taylor method and the Penman- Monteith method.  The two latter methods are considered standard methods for estimating ET but require a larger number of meteorological parameters some of which are not readily available at many weather stations.  The rationale for doing this work was to make estimated ET more readily available for ET-based irrigation scheduling tools.  The paper will present modifications we made to Hangreaves – Samani method to make it more accurate for the Southeast and present results comparing the three methods.