Comparison of methods for estimating reference evapotranspiration (ETo) for Rahuri region

Abstract

Penman Monteith (FAO56-PMM), Modified Penman FAO-24 (MPM), Hargreaves-Samani (HSM), FAO-24 Pan Evaporation (FPEM), Blaney-Criddle (BCM) and FAO Radiation (FRM) methods were used for estimation of ETo for Rahuri region. The Penman Monteith method was considered as the standard of comparison for evaluating the other five methods. The ETo values estimated by PMM were correlated with ETo values estimated by other five methods. The good correlation was found between the ET o values estimated by MPM, HSM and FRM. The coefficient of determination was high for MPM (R 2=0.99), HSM (R2=0.97) and FRM (R2=0.93) and therefore found to be more suitable in the absence of adequate climate data for the use of PMM for this climatic region.

Keywords

• Reference evapotranspiration
• PMM
• MPM
• HSM
• FPEM
• BCM