The Performance of Thirty-Eight Evapotraspiation Methods against the Penman Montieth Method

Evapotranspiration is an important parameter to know in the management of agricultural water resources. There are several methods for estimating evapotranspiration (ETo). The FAO Penman-Monteith method considered universal standard ETo, however, climate data needed calculate ETo not always available, so it necessary evaluate performance using equations as a comparison evapotranspiration. This study aims find 38 empirical against Penman Monteith and climatological parameters that most influence accuracy calculations. used form Bora Station which represents land settlement areas, Boladangko representing mountainous areas Singkoyo coastal with observation period 32 years (1986-2017). was evaluated PE, RMSE, MAE, MR slope methods. results this indicate that: Makkink method, Abtew1, Irmak et al., Tabari & Talaee1, Valiantzas1 Abtew3 showed excellent performance, while WMO Mahringer performed poorly three research locations; number had no significant effect on obtained. use temperature solar radiation calculation has greatest value.