1i.albedo(1)                   Grass User's Manual                  i.albedo(1)
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NAME

6       i.albedo  - Computes broad band albedo from surface reflectance.
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KEYWORDS

9       imagery, albedo, reflectance, satellite, Landsat, ASTER, AVHRR, MODIS
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SYNOPSIS

12       i.albedo
13       i.albedo --help
14       i.albedo  [-mnl8acd]  input=name[,name,...]  output=name  [--overwrite]
15       [--help]  [--verbose]  [--quiet]  [--ui]
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17   Flags:
18       -m
19           MODIS (7 input bands:1,2,3,4,5,6,7)
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21       -n
22           NOAA AVHRR (2 input bands:1,2)
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24       -l
25           Landsat 5+7 (6 input bands:1,2,3,4,5,7)
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27       -8
28           Landsat 8 (7 input bands:1,2,3,4,5,6,7)
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30       -a
31           ASTER (6 input bands:1,3,5,6,8,9)
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33       -c
34           Aggressive mode (Landsat)
35           Albedo  dry  run  to  calculate  some  water  to  beach/sand/desert
36           stretching, a kind of simple atmospheric correction
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38       -d
39           Soft mode (MODIS)
40           Albedo  dry  run  to  calculate  some  water  to  beach/sand/desert
41           stretching, a kind of simple atmospheric correction
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43       --overwrite
44           Allow output files to overwrite existing files
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46       --help
47           Print usage summary
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49       --verbose
50           Verbose module output
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52       --quiet
53           Quiet module output
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55       --ui
56           Force launching GUI dialog
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58   Parameters:
59       input=name[,name,...] [required]
60           Name of input raster map
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62       output=name [required]
63           Name for output raster map
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DESCRIPTION

66       i.albedo  calculates  the  albedo,  that  is  the   Shortwave   surface
67       reflectance  in  the  range  of  0.3-3 micro-meters.  It takes as input
68       individual bands of surface reflectance originating from MODIS,  AVHRR,
69       Landsat or Aster satellite sensors and calculates the albedo for those.
70       This is a precursor to r.sun and any energy-balance processing.
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NOTES

73       It uses for Landsat 8 the weighted average reflectance (temporary solu‐
74       tion until an algorithm is found).
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76       It assumes MODIS product surface reflectance in [0;10000].
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EXAMPLE

79       The  following  example creates the raster map "albedo_lsat7_1987" from
80       the LANDSAT-TM5 bands in the North Carolina dataset:
81       g.region raster=lsat5_1987_10 -p
82       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
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84       Figure: Resulting albedo map from LANDSAT 5
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86       The following example creates the raster map  "albedo_lsat7_2000"  from
87       the LANDSAT-TM7 bands in the North Carolina dataset:
88       g.region raster=lsat7_2000_10 -p
89       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
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91       Figure: Resulting albedo map from LANDSAT 7
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TODO

94       Maybe change input requirement of MODIS to [0.0-1.0]?
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SEE ALSO

97        r.sun, i.vi
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References

100       For a 2 band determination of the Aster BB Albedo see the following:
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102       Salleh  and Chan, 2014. Land Surface Albedo Determination: Remote Sens‐
103       ing and Statistical Validation. in proceedings of FIG 2014 (PDF)
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AUTHOR

106       Yann Chemin
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SOURCE CODE

109       Available at: i.albedo source code (history)
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111       Main index | Imagery index | Topics index | Keywords index |  Graphical
112       index | Full index
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114       © 2003-2019 GRASS Development Team, GRASS GIS 7.8.2 Reference Manual
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118GRASS 7.8.2                                                        i.albedo(1)