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Table 1

Equations used for estimating reference plant evapotranspiration

ModelEquationReference
FAO B-C 

 
Doorenbos & Pruitt (1977)  
FAO P-M  Allen et al. (1998)  
H-S  Hargreaves & Samani (1985)  
Irmak  Irmak et al. (2003)  
Priestley  Priestley & Taylor (1972)  
 
Turc  RH > 50%, Turc (1961)  
RH < 50%, 
Thornthwaite 
 
Thornthwaite (1948)  
Jensen-Hayes CT = 0.25, Tx = −3 Jensen & Haise (1963)  
ModelEquationReference
FAO B-C 

 
Doorenbos & Pruitt (1977)  
FAO P-M  Allen et al. (1998)  
H-S  Hargreaves & Samani (1985)  
Irmak  Irmak et al. (2003)  
Priestley  Priestley & Taylor (1972)  
 
Turc  RH > 50%, Turc (1961)  
RH < 50%, 
Thornthwaite 
 
Thornthwaite (1948)  
Jensen-Hayes CT = 0.25, Tx = −3 Jensen & Haise (1963)  
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