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i.eb.eta

Actual evapotranspiration for diurnal period (Bastiaanssen, 1995).

i.eb.eta netradiationdiurnal=name evaporativefraction=name temperature=name output=name [--overwrite] [--verbose] [--quiet] [--qq] [--ui]

Example:

i.eb.eta netradiationdiurnal=rnetday evaporativefraction=evapfr temperature=tempk output=name

grass.script.run_command("i.eb.eta", netradiationdiurnal="rnetday", evaporativefraction="evapfr", temperature="tempk", output, overwrite=False, verbose=False, quiet=False, superquiet=False)

Example:

gs.run_command("i.eb.eta", netradiationdiurnal="rnetday", evaporativefraction="evapfr", temperature="tempk", output="name")

Parameters

netradiationdiurnal=name [required]
    Name of the diurnal net radiation map [W/m2]
    Default: rnetday
evaporativefraction=name [required]
    Name of the evaporative fraction map [-]
    Default: evapfr
temperature=name [required]
    Name of the surface skin temperature [K]
    Default: tempk
output=name [required]
    Name of the output actual evapotranspiration layer [mm/d]
--overwrite
    Allow output files to overwrite existing files
--help
    Print usage summary
--verbose
    Verbose module output
--quiet
    Quiet module output
--qq
    Very quiet module output
--ui
    Force launching GUI dialog

netradiationdiurnal : str, required
    Name of the diurnal net radiation map [W/m2]
    Used as: input, raster, name
    Default: rnetday
evaporativefraction : str, required
    Name of the evaporative fraction map [-]
    Used as: input, raster, name
    Default: evapfr
temperature : str, required
    Name of the surface skin temperature [K]
    Used as: input, raster, name
    Default: tempk
output : str, required
    Name of the output actual evapotranspiration layer [mm/d]
    Used as: output, raster, name
overwrite: bool, optional
    Allow output files to overwrite existing files
    Default: False
verbose: bool, optional
    Verbose module output
    Default: False
quiet: bool, optional
    Quiet module output
    Default: False
superquiet: bool, optional
    Very quiet module output
    Default: False

DESCRIPTION

i.eb.eta calculates the actual evapotranspiration (ETa ; mm/d) for diurnal period after [1], implemented in [3]. It takes input of Diurnal Net Radiation (see r.sun), evaporative fraction (see i.eb.evapfr) and surface skin temperature.

NOTES

Full ETa processing will need those:

  • i.vi, i.albedo, r.latlong, i.emissivity
  • i.evapo.potrad (GRASS Addon)
  • i.eb.netrad, i.eb.soilheatflux, i.eb.hsebal01
  • i.eb.evapfr, i.eb.eta

(for time integration: i.evapo.time_integration)

For more details on the algorithms see [1][2][3][4].

REFERENCES

[1] Bastiaanssen, W.G.M., 1995. Estimation of Land surface parameters by remote sensing under clear-sky conditions. PhD thesis, Wageningen University, Wageningen, The Netherlands. (PDF)

[2] Chemin Y., Alexandridis T.A., 2001. Improving spatial resolution of ET seasonal for irrigated rice in Zhanghe, China. Asian Journal of Geoinformatics. 5(1):3-11,2004.

[3] Alexandridis T.K., Cherif I., Chemin Y., Silleos N.G., Stavrinos E., Zalidis G.C. Integrated methodology for estimating water use in Mediterranean agricultural areas. Remote Sensing. 2009, 1, 445-465. (PDF)

[4] Chemin, Y., 2012. A Distributed Benchmarking Framework for Actual ET Models, in: Irmak, A. (Ed.), Evapotranspiration - Remote Sensing and Modeling. InTech. (PDF)

SEE ALSO

r.sun, i.eb.evapfr, i.eb.netrad

AUTHOR

Yann Chemin, Asian Institute of Technology, Thailand

SOURCE CODE

Available at: i.eb.eta source code (history)
Latest change: Friday Feb 07 19:16:09 2025 in commit a82a39f