.TH i.albedo 1grass "" "GRASS 8.3.1" "GRASS GIS User's Manual"
.SH NAME
\fI\fBi.albedo\fR\fR  \- Computes broad band albedo from surface reflectance.
.SH KEYWORDS
imagery, albedo, reflectance, satellite, Landsat, ASTER, AVHRR, MODIS
.SH SYNOPSIS
\fBi.albedo\fR
.br
\fBi.albedo \-\-help\fR
.br
\fBi.albedo\fR [\-\fBmnl8acd\fR] \fBinput\fR=\fIname\fR[,\fIname\fR,...] \fBoutput\fR=\fIname\fR  [\-\-\fBoverwrite\fR]  [\-\-\fBhelp\fR]  [\-\-\fBverbose\fR]  [\-\-\fBquiet\fR]  [\-\-\fBui\fR]
.SS Flags:
.IP "\fB\-m\fR" 4m
.br
MODIS (7 input bands:1,2,3,4,5,6,7)
.IP "\fB\-n\fR" 4m
.br
NOAA AVHRR (2 input bands:1,2)
.IP "\fB\-l\fR" 4m
.br
Landsat 5+7 (6 input bands:1,2,3,4,5,7)
.IP "\fB\-8\fR" 4m
.br
Landsat 8 (7 input bands:1,2,3,4,5,6,7)
.IP "\fB\-a\fR" 4m
.br
ASTER (6 input bands:1,3,5,6,8,9)
.IP "\fB\-c\fR" 4m
.br
Aggressive mode (Landsat)
.br
Albedo dry run to calculate some water to beach/sand/desert stretching, a kind of simple atmospheric correction
.IP "\fB\-d\fR" 4m
.br
Soft mode (MODIS)
.br
Albedo dry run to calculate some water to beach/sand/desert stretching, a kind of simple atmospheric correction
.IP "\fB\-\-overwrite\fR" 4m
.br
Allow output files to overwrite existing files
.IP "\fB\-\-help\fR" 4m
.br
Print usage summary
.IP "\fB\-\-verbose\fR" 4m
.br
Verbose module output
.IP "\fB\-\-quiet\fR" 4m
.br
Quiet module output
.IP "\fB\-\-ui\fR" 4m
.br
Force launching GUI dialog
.SS Parameters:
.IP "\fBinput\fR=\fIname[,\fIname\fR,...]\fR \fB[required]\fR" 4m
.br
Name of input raster map
.IP "\fBoutput\fR=\fIname\fR \fB[required]\fR" 4m
.br
Name for output raster map
.SH DESCRIPTION
\fIi.albedo\fR calculates the albedo, that is the Shortwave surface
reflectance in the range of 0.3\-3 micro\-meters.  It takes as input
individual bands of surface reflectance originating from MODIS, AVHRR, Landsat
or Aster satellite sensors and calculates the albedo for those.  This is
a precursor to \fIr.sun\fR and any energy\-balance processing.
.SH NOTES
It uses for Landsat 8 the weighted average reflectance (temporary solution
until an algorithm is found).
.PP
It assumes MODIS product surface reflectance in [0;10000].
.SH EXAMPLE
The following example creates the raster map \(dqalbedo_lsat7_1987\(dq from the
LANDSAT\-TM5 bands in the North Carolina dataset:
.br
.nf
\fC
g.region raster=lsat5_1987_10 \-p
i.albedo \-l input=lsat5_1987_10,lsat5_1987_20,lsat5_1987_30,lsat5_1987_40,lsat5_1987_50,lsat5_1987_70 output=albedo_lsat7_1987
\fR
.fi
.PP
.br
\fIFigure: Resulting albedo map from LANDSAT 5\fR
.PP
The following example creates the raster map \(dqalbedo_lsat7_2000\(dq from the
LANDSAT\-TM7 bands in the North Carolina dataset:
.br
.nf
\fC
g.region raster=lsat7_2000_10 \-p
i.albedo \-l input=lsat7_2000_10,lsat7_2000_20,lsat7_2000_30,lsat7_2000_40,lsat7_2000_50,lsat7_2000_70 output=albedo_lsat7_2000
\fR
.fi
.PP
.br
\fIFigure: Resulting albedo map from LANDSAT 7\fR
.SH TODO
Maybe change input requirement of MODIS to [0.0\-1.0]?
.SH References
For a 2 band determination of the Aster BB Albedo see the following:
.PP
Salleh and Chan, 2014. Land Surface Albedo Determination: Remote Sensing
and Statistical Validation. in proceedings of FIG 2014
(PDF)
.SH SEE ALSO
\fI
r.sun,
i.vi
\fR
.SH AUTHOR
Yann Chemin
.SH SOURCE CODE
.PP
Available at:
i.albedo source code
(history)
.PP
Accessed: Sunday Dec 17 17:22:37 2023
.PP
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.PP
© 2003\-2023
GRASS Development Team,
GRASS GIS 8.3.1 Reference Manual