The Fourth Reprocessing ATSR-1 and ATSR-2 datasets were generated using a new chain, using some components of the Archive Product Processor (APP) developed with funding from DECC/BEIS: (1) Ungridded Brightness Temperature (UBT) scenes to orbit-length Level 1A, (2) Level 1A to Level 1B.
The processors used were:

• UBT scenes to orbit-length Level 1A: CfE v2.20

• Level 1A to Level 1B: FAST v2.0.5

These versions were used for both datasets

The processor configuration used for the Third Reprocessing of ATSR data was     :

• Level 1 (TOA) processor: STEP/1.4

Information on Auxiliary datafiles is given at https://earth.esa.int/eogateway/instruments/atsr/auxiliary-data.