i.eb.hsebal011grass
Computes sensible heat flux iteration sebal 01.
Usage
i.eb.hsebal01
i.eb.hsebal01 --help
i.eb.hsebal01 [-ac]
netradiation=name
soilheatflux=name
aerodynresistance=name
temperaturemeansealevel=name
vapourpressureactual=name
frictionvelocitystar=float
[row_wet_pixel=float]
[column_wet_pixel=float]
[row_dry_pixel=float]
[column_dry_pixel=float]
output=name
[--overwrite]
[--help]
[--verbose]
[--quiet]
[--ui]
Keywords
imagery, energy balance, soil moisture, evaporative fraction, SEBAL
Overview
i.eb.hsebal01 will calculate the sensible heat flux map (h0), given both maps of Net Radiation and soil Heat flux (Rn, g0) at instantaneous time, the surface roughness (z0m), a map of the altitude corrected temperature (t0dem), a point data of the frictional velocity (u*), a value of actual vapour pressure (ea[KPa]) and the (x,y) pairs for wet and dry pixels. Full process 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)
i.eb.hsebal01 performs the computation of sensible heat flux [W/m2] after Bastiaanssen, 1995 in [1], used in this form in 2001 by [2]. Implemented in this code in [3].
Notes
- •
-
z0m can be alculated by i.eb.z0m or i.eb.z0m0 (GRASS Addons).
- •
-
ea can be calculated with standard meteorological data.
eoTmin=0.6108*EXP(17.27*Tmin/(Tmin+237.3))
eoTmax=0.6108*EXP(17.27*Tmax/(Tmax+237.3))
ea=(RH/100)/((eoTmin+eoTmax)/2)
- •
-
t0dem = surface temperature + (altitude * 0.627 / 100)
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)
Source code
Available at: i.eb.hsebal01 source code (history)
Accessed: Monday Feb 24 17:51:32 2025
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Releases
5 releases since Debian 9 (Stretch); the text changed 4 times.