ADV_Ver2.60

      - bug in surface relectance calculations is corrected
      - GBTData is now input to cloud tests 1,3,4 for glint check 
      - cloud test forward only for ocean retrieval in ADVcoarse
      - option to run locations with Autoretrieve_loc.sh; AATSRparas.dat  has been modified
      - bug in k-ratio iteration has been corrected; possibility to iterrate k-ratio is hard coded (need to change wl=40 to wl=4)

ADV_Ver2.30

      - grift correction is taken away for new AATSR data release;
      - bugs in cloud screening corrected
      

ADV_Ver2.21

      - fine(1x1 km2 resolution) and coarse(10x10km2 resolution) versions are combined
      - cloud retrieval for fine resolution version is implemented
      - bug in surface relectance calculations is corrected
      - Added snow flag calculations to ADVfine

AATSR_ADV.v1.43

      - algorithm corrected to be used for ATSR2

AATSR_ADV.v1.42
       - Forward pixel (i+2, j+1) collocated to nadir (i,j)
       - "bug" in surface reflectance module is corrected


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More detailed explanation of sub-directories L2 and L3.

Level 2, directory L2:
Resolution - 10x10 km2 sinusoidal
Format NetCDF version 4.1.1

Latitude, Longitude (Vectors)
AOD - at 550, 670, 870 (over ocean only) and 1600 nm (Vectors)
Confidence measure - determined using variance of reflectance at 550 nm. Values over 1 are considered to
                  indicate unreliable results (Vectors)

Level 3, directory L3:
daily files
Resolution - 1 degree x 1 degree
Format NetCDF version 4.1.1

Latitude, Longitude (Vectors)
AOD - at 550, 670 and 1600 nm (Matrix)
Confidence measure - determined using variance of reflectance at 550 nm. Values over 1 are considered to
                  indicate unreliable results (Matrix). NOTE: when averaging from level 2 to level 3
                  results having confidence over 1 are discarded.


L3_orbits direcory:
same as L3, but individual orbits