Spatial‐temporal evaluation of different reference evapotranspiration methods based on the climate forecast system reanalysis data

A new study reveals that the Hargreaves–Samani method, a simple temperature-based approach, outperforms other evapotranspiration estimation techniques when applied to the Omo-Gibe basin in Ethiopia. This finding is significant for regions with limited climatological data, as it suggests that this method can reliably estimate grass reference evapotranspiration (ETo) despite regional climate and elevation variations. The research, conducted using Climate Forecast System Reanalysis (CFSR) data from 1979 to 2013, also proposes calibrated coefficients for the Hargreaves–Samani equation to enhance its performance. Additionally, the study highlights that annual ETo trends do not always align with true evapotranspiration patterns, emphasizing the need for careful interpretation of such trends in data-scarce regions.

Woldesenbet, T. A., & Elagib, N. A. (2021). Spatial‐temporal evaluation of different reference evapotranspiration methods based on the climate forecast system reanalysis data. Hydrological Processes, 35(6). Portico. https://doi.org/10.1002/hyp.14239