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the mothod to calculate the monthly evapotranspiration in the Seasonal Water yield model?

     Does anyone who know the method to calculate the the monthly actual evapotranspiration in the Seasonal Water yield model? After searching the model guide book, I get nothing from it ,Can anyone who could show me the method or the theory to calculate the monthly actual evapotranspiration or the literature I can search, thank you!


  • swolnyswolny Member, NatCap Staff
    Hi @Liwei_hello -

    The model calculates actual evapotranspiration using equation 4 in the User Guide. Do you have a particular question about these equations?

    ~ Stacie

  • Hi@swolny ,thanks a lot for your answer,where does the equation derive from?do you have some literatures to illustrate its theory? thank you
  • swolnyswolny Member, NatCap Staff
    I just asked our hydrologist, and she said that the AET equation is from the FAO Irrigation and Drainage Paper 56:

    Allen, R. G., Pereira, L. S., Raes, D., & Smith, M. (1998). Crop evapotranspiration - Guidelines for computing crop water requirements (FAO Irrigation and drainage paper 56). Rome, Italy.

    It's the empirical equation translating ref. ET into actual ET. Apologies that this reference is missing from the User Guide.

    ~ Stacie
  • @swonly,thank you very much!
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