i.eb.evapfr(1grass)

i.eb.evapfr 💧✨ <small>(1grass)</small>

okay bestie so this is the GRASS User's Manual page for i.eb.evapfr, and it is literally the girlboss of soil moisture. she computes evaporative fraction and root zone soil moisture and she does NOT miss. 💅

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🌸 NAME 🌸

i.eb.evapfr — she computes evaporative fraction and root zone soil moisture. that's it, that's the job description, no cap.

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🎀 KEYWORDS 🎀

imagery, energy balance, soil moisture, evaporative fraction, SEBAL

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✨ SYNOPSIS ✨

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

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🦋 Flags 🦋

• -m — this one gives you the root zone soil moisture output, per Makin, Molden and Bastiaanssen, 2001. slay.
• --overwrite — lets your output files just go ahead and overwrite existing files. chaotic but permitted.
• --help — prints the usage summary, i.e. the "hey bestie here's how you use me" moment.
• --verbose — verbose module output, so she tells you everything she's doing. main character energy fr.
• --quiet — shhh. quiet module output. she's not gonna chat.
• --ui — force launches the GUI dialog. for the visual learners 🫶

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🌈 Parameters 🌈

• netradiation=name [required] — the name of your Net Radiation raster map, in [W/m2].
• soilheatflux=name [required] — the name of your soil heat flux raster map, in [W/m2].
• sensibleheatflux=name [required] — the name of your sensible heat flux raster map, in [W/m2].
• evaporativefraction=name [required] — the name for your output evaporative fraction raster map. you pick it, she writes it 💖
• soilmoisture=name — the name for your output root zone soil moisture raster map. optional, but like. iconic if you use it.

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💜 DESCRIPTION 💜

i.eb.evapfr calculates the evaporative fraction after Bastiaanssen 1995. the main implementation follows Alexandridis et al. (2009). ngl that's a whole pedigree.

she takes as input:

• the net radiation (see r.sun, i.eb.netrad)
• the soil heat flux (see i.eb.soilheatflux)
• the sensible heat flux (see i.eb.hsebal01)

and a flag adds a root zone empirical soil moisture output, straight from the article of Bastiaanssen, et al. (2000). periodt.

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📚 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)

like hello, the reading list is giving academia 💀📖

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👀 SEE ALSO 👀

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

(the whole friend group, all linked up 🫶)

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👑 AUTHOR 👑

Yann Chemin, Asian Institute of Technology, Thailand

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🔥 SOURCE CODE 🔥

Available at: i.eb.evapfr source code (history)

Latest change: Wednesday May 07 12:54:49 2025 in commit: 6b2b2553b3c72a32fb9c4ee6ba3110239c361f10

Main index | Imagery index | Topics index | Keywords index | Graphical index | Full index

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and that's the whole page bestie, we ate and left zero crumbs ✨💖

© 2003-2026 GRASS Development Team, GRASS 8.5.0 Reference Manual — she's i.eb.evapfr(1grass) and she's been That Girl since 2003. 🎀🌸🦋