Can we use PET to replace ETo in Water-yield model?
I am a bit confusing about which data of evatranspiration that I can use in water-yield model. As shown in the User Guide of InVEST 3.2.2, it seems to me that I could use PET to replace ETo (page 126).
I got PET raster from http://www.cgiar-csi.org/, can I use this raster directly? Or is there a way to calculate ETo raster from this PET raster?
Thank you very much,
I quoted the method of calculating ETo as shown in page 126:
"The reference evapotranspiration could be also calculated monthly and annually using the Hamon equation
(Hamon 1961, Wolock and McCabe 1999):