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Review of Relevant Evapotranspiration Models for Estimating Reference Evapotranspiration

Tom Cyprian, Edet, J. A, Sam, E. O, Ahaneku, I. E, Igbozulike, A. O.


The word evapotranspiration (ET) is a very pivotal component of the hydrological cycle, and it has a very crucial but accurate design and operation in terms of management of irrigation systems. Its evaluation by direct measurement using lysimeters, atmometers, energy balance or pan evaporimeter is not usually feasible because it is complex, expensive and time consuming. Therefore, relevant indirect methods such as FAO–56 Penman–Monteith (PM), Priestly Taylor (PT), Blaney–Morin Nigeria (BMN) and Hargreaves–Samani (HS), etc. were studied and recommended for planning purposes by agriculturist, engineers, hydrologists, and environmentalists. These models are adjudged to be site or location specific by researchers.


Evapotranspiration, models, hydrological cycle, lysimeters, atmometers

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