online_hargreaves:   Potential evapotranspiration by the Hargreaves formula
Formulas

Tr = Tmax - Tmin

Ra = 10 [Qn/(ρH]

ETo = 0.0023 Ra (Tmean + 17.8) Tr0.5

Reference

• Hargreaves, G.H. and R.G. Allen. 2003:  History and Evaluation
of Hargreaves Evapotranspiration Equation.
INPUT DATA:

[Description]       [Sample input]

Net radiation Qn (cal cm-2 d-1):    

Minimum air temperature Tmin (oC):    

Mean air temperature Tmean (oC):    

Maximum air temperature Tmax (oC):    

Please enter input data and press 'Calculate'.

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