online_penman_monteith:   Potential evapotranspiration by Penman-Monteith


(es-ea) ≅ (eo-ea) = eo[1 + (φ/100)]

En = Qn/(ρλ)

Ea = 86400[(ρacp)/(ρλγ)](es-ea)(rs+ra)-1

Δ = (0.00815 Ta + 0.8912)7

γ∗ = γ [1 + (rs/ra)]

E = (ΔEn + γ∗Ea)/(Δ + γ∗)



Air temperature Ta (oC):    

Net radiation Qn (cal cm-2 d-1):    

Relative humidity RH (%):    

Wind velocity v2 (km d-1):    

Atmospheric pressure p (mb):    


Please enter input data and press 'Calculate'.

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