PET_hg: Estimate ET0 by Hargreaves equation.
In rpkgs/hydroTools: Tools for hydrological model

PET_hg

R Documentation

Estimate ET0 by Hargreaves equation.

Estimate reference evapotranspiration (ET0) from a hypothetical short grass reference surface using the the Hargreaves equation.

PET_hg(Tmax, Tmin, Tavg = NULL, Rsi_toa = NULL, lat = NULL, dates = NULL)

`Tmax`	Daily maximum air temperature at 2m height `⁠[deg Celsius]⁠`.
`Tmin`	Daily minimum air temperature at 2m height `⁠[deg Celsius]⁠`.
`Tavg`	Daily mean air temperature at 2m height `⁠[deg Celsius]⁠`. If not provided it would estimated by averaging the Tmax and tmin.
`Rsi_toa`	Clear sky incoming shortwave radiation, i. e. extraterrestrial radiation multiply by clear sky transmissivity (i. e. a + b, a and b are coefficients of Angstrom formula. Normally 0.75) `⁠[MJ m-2 day-1]⁠`. If not provided, must provide lat and dates.
`lat`	Latitude `⁠[degree]⁠`.
`dates`	A R Date type of a vector of Date type. If not provided, it will Regard the ssd series is begin on the first day of a year.