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When downloading Landsat 8 OLI/TIRS Land Surface Reflectance from the USGS earthexplorer service, the usual archive has the following files in it :

LC82330672013150LGN00_B10.TIF
LC82330672013150LGN00_B11.TIF
LC82330672013150LGN00_B1.TIF
...
LC82330672013150LGN00_B9.TIF
LC82330672013150LGN00_BQA.TIF
LC82330672013150LGN00_MTL.txt

For some scenes (e.g. LC82270652013236LGN00) though, we get the following

LC82270652013236LGN00_cfmask_conf.tif
LC82270652013236LGN00_cfmask.tif
LC82270652013236LGN00_sr_band1.tif
...
LC82270652013236LGN00_sr_band6.tif
LC82270652013236LGN00_sr_band7.tif
LC82270652013236LGN00_sr_cloud.tif
LC82270652013236LGN00.xml

The data stored in the .tif files is very different. When the _MTL.txt file is present, we have band 3 values from 6000 to 10000 for a scene in the amazonian forest. But when the .xml file is present, the values range from 0 to about 1500 (also for an amazonian forest scene which should have similar histogram).

All of the Landsat 8 information I could find assumes we get the _MTL.txt file and I was unable to find any information about the other one. There doesn't seem to be any option in earthexplorer to control which type of data you want to download.

Does someone know how to convert between the two ?

3

The difference that you see arise from having a mix of 'surface reflectance' data, and 'uncorrected' / 'raw' data.
The scenes with a MTL.txt are 'uncorrected' while the ones with the xml files are 'surface reflectance'.
I am uncertain as to why you have a mix of the two data types, but something must have gone wrong in the ordering or the processing of data.

It should be noted that when downloading the 'surface reflectance' product, you are supposed to get the xml files. The scenes where you have a MTL file are not atmospherically corrected, and will at times be difficult to compare over time or between different path / rows.

  • 1
    Ok actually I figured it out, it depends on the dataset you select in earthexplorer : If you select Landsat Surface Reflectance - L8 OLI/TIRS, you get the corrected ones (with xml) and if you select L8 OLI/TIRS, you get the uncorrected ones (with the MTL.txt). Kind of obvious in retrospect, but I didn't check carefully enough when selecting the dataset. Thanks for the explanation ! – Julien May 27 '16 at 15:15

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