[GRASS-user] Estimating Albedo from Landsat

Nikos Alexandris nikos.alexandris at felis.uni-freiburg.de
Sun Sep 12 20:35:29 EDT 2010


Daniel Victoria:

> I haven't tryed i.landsat.toar addon but from what I read in the wiki
> (http://grass.osgeo.org/wiki/Atmospheric_correction) I could either
> use i.landsat.toar or a DN - Radiance conversion formula that is
> given...
 
> Will try to recalculate the images, I might have done something wrong

Hi Daniel!

Did you finally used i.landsat.toar for the Landsat5 - TM bands?

I am trying to use the module on the LT51830332007248MOR00 image(s) and have 
several (expected) problems, like:

(note that the metadata file I downloaded via GLOVis has a ".meta" extension)

1. the "LT51830332007248MOR00.meta" isn't read correctly or the module is 
looking for a string other than the "date_acquired = 20070905" string which is 
the only "date-string" included in the ".meta" file

2. does not recognize the solar elevation value

(the above "cases" are mentioned in the manual, so manual feed is required 
here)

3. after manually providing the "solar_elevation" and the "product_date" and 
using the "-v" flag, some random (?) segfaults occur.

4. without the "-v" flag it runs but seems to take too much time? OK, the 
image set is large ( 7654 cols x 7127 rows x 7 bands). --- Is it really taking 
so long or is there something wrong?

Nikos


More information about the grass-user mailing list