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NAME

i.evapo.mh - Computes evapotranspiration calculation modified or original Hargreaves formulation, 2001.

KEYWORDS

imagery, evapotranspiration

SYNOPSIS

i.evapo.mh
i.evapo.mh help
i.evapo.mh [-zhs] netradiationdiurnal=name averagetemperature=name minimumtemperature=name maximumtemperature=name precipitation=name output=name [--overwrite] [--verbose] [--quiet]

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
--verbose
Verbose module output
--quiet
Quiet module output

Parameters:

netradiationdiurnal=name
Name of input diurnal net radiation raster map [W/m2/d]
averagetemperature=name
Name of input average air temperature raster map [C]
minimumtemperature=name
Name of input minimum air temperature raster map [C]
maximumtemperature=name
Name of input maximum air temperature raster map [C]
precipitation=name
Name of precipitation raster map [mm/month]
Disabled for original Hargreaves (1985)
output=name
Name for output raster map [mm/d]

DESCRIPTION

i.evapo.MH Calculates the reference ET after Hargreaves (1985) and Modified Hargreaves (2001).

NOTES

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., and R.G. Allen. 2002. Estimating reference evapotranspiration under inaccurate data conditions. Irrigation and Drainage Systems 16: 33-45. Hargreaves and Samani, 1985.

TODO

SEE ALSO

i.evapo.PT
i.evapo.PM
i.evapo.potrad
r.sun

AUTHORS

Yann Chemin, GRASS Development team, 2007-2011

Last changed: $Date: 2011-01-12 08:16:10 -0800 (Wed, 12 Jan 2011) $


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