etp_hs: Potential evapo-transpiration sensu Hargreaves-Samani

In achtmalklug/Retp:

Description

Calculates potential evapo-transpiration from air temperature extremes using the approach by Hargreaves&Samani (1985) and popular corrections.

Usage

etp_hs(lat, day, tmin, tmax, tmean = (tmax + tmin)/2, alt, ke = 0.0135,
  kt = 0.16, kmethod, ...)

Arguments

tmin	minimum air temperature (°C)
tmax	maximum air temperature (°C)
tmean	mean air temperature (°C). Deafults to (tmin+tmax)/2
alt	elevation above sea level (m)
ke	calibration coefficient for Hargreaves' ETP function
kt	calibration coefficient for Hargreaves' irradiance estimation.
kmethod	Method to use for estimating the kt parameter in the Hargreaves equation. One of "anadale", "allen", "samani".

Value

Potential evapo-transpiration in mm per period.

Examples

etp_hs(lat=20,day=45,tmin=1,tmax=7)

achtmalklug/Retp documentation built on June 7, 2019, 12:47 a.m.