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NAME

i.eb.hsebal01 - Computes sensible heat flux iteration SEBAL 01.

KEYWORDS

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

SYNOPSIS

i.eb.hsebal01
i.eb.hsebal01 --help
i.eb.hsebal01 [-ac] netradiation=name soilheatflux=name aerodynresistance=name temperaturemeansealevel=name frictionvelocitystar=float vapourpressureactual=float [row_wet_pixel=float] [column_wet_pixel=float] [row_dry_pixel=float] [column_dry_pixel=float] output=name [--overwrite] [--help] [--verbose] [--quiet] [--ui]

Flags:

-a
Automatic wet/dry pixel (careful!)
-c
Dry/Wet pixels coordinates are in image projection, not row/col
--overwrite
Allow output files to overwrite existing files
--help
Print usage summary
--verbose
Verbose module output
--quiet
Quiet module output
--ui
Force launching GUI dialog

Parameters:

netradiation=name [required]
Name of instantaneous net radiation raster map [W/m2]
soilheatflux=name [required]
Name of instantaneous soil heat flux raster map [W/m2]
aerodynresistance=name [required]
Name of aerodynamic resistance to heat momentum raster map [s/m]
temperaturemeansealevel=name [required]
Name of altitude corrected surface temperature raster map [K]
frictionvelocitystar=float [required]
Value of the height independent friction velocity (u*) [m/s]
Default: 0.32407
vapourpressureactual=float [required]
Value of the actual vapour pressure (e_act) [KPa]
Default: 1.511
row_wet_pixel=float
Row value of the wet pixel
column_wet_pixel=float
Column value of the wet pixel
row_dry_pixel=float
Row value of the dry pixel
column_dry_pixel=float
Column value of the dry pixel
output=name [required]
Name for output sensible heat flux raster map [W/m2]

Table of contents

DESCRIPTION

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: (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

SEE ALSO

i.eb.soilheatflux, i.eb.hsebal01, i.eb.evapfr

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)

AUTHORS

Yann Chemin, International Rice Research Institute, Los Banos, The Philippines.

Contact: Yann Chemin

Last changed: $Date: 2015-01-25 09:55:23 -0800 (Sun, 25 Jan 2015) $

SOURCE CODE

Available at: i.eb.hsebal01 source code (history)


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