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kunstler / ClimateNFI

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Compare PET #1

Open kunstler opened 2 years ago

kunstler commented 2 years ago

TerraClimate provide PET at 4 x 4 km based on Penman Montieth We can compute PET with Thornwaite based only on T and Lat or with hargraeaves with tmin tmax and radiation (from WC mean over the period at 1x1km (kJ m-2 day-1) or time varying srad at 2 x 2 km from TerraClimate srad Downward surface shortwave radiation), units = W/m2).

We can compte these PET with this package https://rdrr.io/cran/SPEI/man/PET.html

kunstler commented 2 years ago

in the package radiation are in MJ m-2 d-1. Need to do the conversion wc /1000

Terraclimate W per month ? scale factor 0.1 *3600*24/(1000*1000)

kunstler commented 2 years ago

see https://www.fao.org/3/x0490e/x0490e0i.htm