i.evapo.mh.1grass - Man Page

Computes evapotranspiration calculation modified or original Hargreaves formulation, 2001.

i.evapo.mh i.evapo.mh --help i.evapo.mh [-zhs] netradiation_diurnal=name average_temperature=name minimum_temperature=name maximum_temperature=name [precipitation=name] output=name [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags

-z: Set negative ETa to zero
-h: Use original Hargreaves (1985)
-s: Use Hargreaves-Samani (1985)
--overwrite: Allow output files to overwrite existing files
--help: Print usage summary
--verbose: Verbose module output
--quiet: Quiet module output
--ui: Force launching GUI dialog

Parameters

netradiation_diurnal=nameÂ [required]: Name of input diurnal net radiation raster map [W/m2/d]
average_temperature=nameÂ [required]: Name of input average air temperature raster map [C]
minimum_temperature=nameÂ [required]: Name of input minimum air temperature raster map [C]
maximum_temperature=nameÂ [required]: Name of input maximum air temperature raster map [C]
precipitation=name: Name of precipitation raster map [mm/month]
Disabled for original Hargreaves (1985)
output=nameÂ [required]: Name for output raster map [mm/d]

Description

i.evapo.mh calculates the reference evapotranspiration (ET) after Hargreaves et al. (1985), Hargreaves and Samani (1985) and the Modified Hargreaves version found in Droogers and Allen (2002).

References

Hargreaves GL, Hargreaves GH, Riley JP, 1985. Agricultural benefits for Senegal River Basin. Journal of Irrigation and Drainange Engineering, ASCE, 111(2):113-124.
Droogers P, Allen RG, 2002. Towards a simplified global reference evapotranspiration equation. Irrigation Science.
Droogers, P., Allen RG. 2002. Estimating reference evapotranspiration under inaccurate data conditions. Irrigation and Drainage Systems 16: 33-45.
Hargreaves GH, Samani ZA, 1985. Reference crop evapotranspiration from ambient air temperature. American Society of Agricultural Engineers (Microfiche collection)(USA). no. fiche no. 85-2517.