## DESCRIPTION

i.albedo 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 r.sun and any energy-balance processing.

## NOTES

It uses for Landsat 8 the weighted average reflectance (temporary solution until an algorithm is found).

It assumes MODIS product surface reflectance in [0;10000].

## EXAMPLE

The following example creates the raster map "albedo_lsat7_1987" from the LANDSAT-TM5 bands in the North Carolina dataset:

    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

Figure: Resulting albedo map from LANDSAT 5

The following example creates the raster map "albedo_lsat7_2000" from the LANDSAT-TM7 bands in the North Carolina dataset:

    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

Figure: Resulting albedo map from LANDSAT 7

## TODO

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

## SEE ALSO

r.sun, i.vi

## References

For a 2 band determination of the Aster BB Albedo see the following:

Salleh and Chan, 2014. Land Surface Albedo Determination: Remote Sensing and Statistical Validation. in proceedings of FIG 2014 (PDF)

## AUTHOR

Yann Chemin