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i.eb.evapfr

Computes evaporative fraction and root zone soil moisture.

i.eb.evapfr [-m] netradiation=name soilheatflux=name sensibleheatflux=name evaporativefraction=name [soilmoisture=name] [--overwrite] [--verbose] [--quiet] [--qq] [--ui]

Example:

i.eb.evapfr netradiation=name soilheatflux=name sensibleheatflux=name evaporativefraction=name

grass.script.run_command("i.eb.evapfr", netradiation, soilheatflux, sensibleheatflux, evaporativefraction, soilmoisture=None, flags=None, overwrite=None, verbose=None, quiet=None, superquiet=None)

Example:

gs.run_command("i.eb.evapfr", netradiation="name", soilheatflux="name", sensibleheatflux="name", evaporativefraction="name")

grass.tools.Tools.i_eb_evapfr(netradiation, soilheatflux, sensibleheatflux, evaporativefraction, soilmoisture=None, flags=None, overwrite=None, verbose=None, quiet=None, superquiet=None)

Example:

tools = Tools()
tools.i_eb_evapfr(netradiation="name", soilheatflux="name", sensibleheatflux="name", evaporativefraction="name")

This grass.tools API is experimental in version 8.5 and expected to be stable in version 8.6.

Parameters

netradiation=name [required]
    Name of Net Radiation raster map [W/m2]
soilheatflux=name [required]
    Name of soil heat flux raster map [W/m2]
sensibleheatflux=name [required]
    Name of sensible heat flux raster map [W/m2]
evaporativefraction=name [required]
    Name for output evaporative fraction raster map
soilmoisture=name
    Name for output root zone soil moisture raster map
-m
    Root zone soil moisture output (Makin, Molden and Bastiaanssen, 2001)
--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

netradiation : str, required
    Name of Net Radiation raster map [W/m2]
    Used as: input, raster, name
soilheatflux : str, required
    Name of soil heat flux raster map [W/m2]
    Used as: input, raster, name
sensibleheatflux : str, required
    Name of sensible heat flux raster map [W/m2]
    Used as: input, raster, name
evaporativefraction : str, required
    Name for output evaporative fraction raster map
    Used as: output, raster, name
soilmoisture : str, optional
    Name for output root zone soil moisture raster map
    Used as: output, raster, name
flags : str, optional
    Allowed values: m
    m
        Root zone soil moisture output (Makin, Molden and Bastiaanssen, 2001)
overwrite : bool, optional
    Allow output files to overwrite existing files
    Default: None
verbose : bool, optional
    Verbose module output
    Default: None
quiet : bool, optional
    Quiet module output
    Default: None
superquiet : bool, optional
    Very quiet module output
    Default: None

netradiation : str | np.ndarray, required
    Name of Net Radiation raster map [W/m2]
    Used as: input, raster, name
soilheatflux : str | np.ndarray, required
    Name of soil heat flux raster map [W/m2]
    Used as: input, raster, name
sensibleheatflux : str | np.ndarray, required
    Name of sensible heat flux raster map [W/m2]
    Used as: input, raster, name
evaporativefraction : str | type(np.ndarray) | type(np.array) | type(gs.array.array), required
    Name for output evaporative fraction raster map
    Used as: output, raster, name
soilmoisture : str | type(np.ndarray) | type(np.array) | type(gs.array.array), optional
    Name for output root zone soil moisture raster map
    Used as: output, raster, name
flags : str, optional
    Allowed values: m
    m
        Root zone soil moisture output (Makin, Molden and Bastiaanssen, 2001)
overwrite : bool, optional
    Allow output files to overwrite existing files
    Default: None
verbose : bool, optional
    Verbose module output
    Default: None
quiet : bool, optional
    Quiet module output
    Default: None
superquiet : bool, optional
    Very quiet module output
    Default: None

Returns:

result : grass.tools.support.ToolResult | np.ndarray | tuple[np.ndarray] | None
If the tool produces text as standard output, a ToolResult object will be returned. Otherwise, None will be returned. If an array type (e.g., np.ndarray) is used for one of the raster outputs, the result will be an array and will have the shape corresponding to the computational region. If an array type is used for more than one raster output, the result will be a tuple of arrays.

Raises:

grass.tools.ToolError: When the tool ended with an error.

DESCRIPTION

i.eb.evapfr calculates the evaporative fraction after Bastiaanssen 1995. The main implementation follows Alexandridis et al. (2009). The module takes as input the net radiation (see r.sun, i.eb.netrad), soil heat flux (see i.eb.soilheatflux) and sensible heat flux (see i.eb.hsebal01). A flag adds a root zone empirical soil moisture output from the article of Bastiaanssen, et al. (2000).

REFERENCES

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)

Bastiaanssen, W.G.M., Molden, D.J., Makin, I.W., 2000. Remote sensing for irrigated agriculture: examples from research and possible applications. Agricultural water management 46.2: 137-155.

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.

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

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

SEE ALSO

i.eb.hsebal01, i.eb.netrad, i.eb.soilheatflux, r.sun

AUTHOR

Yann Chemin, Asian Institute of Technology, Thailand

SOURCE CODE

Available at: i.eb.evapfr source code (history)
Latest change: Wednesday May 07 12:54:49 2025 in commit 6b2b255