The ATOVS and AVHRR Processing Package (AAPP)

AAPP processes data from instruments on board the NOAA polar orbiting satellites - namely HIRS, AVHRR, AMSU and MHS on the current generation of satellites. It also processes data from HIRS, AVHRR, AMSU, MHS and IASI on the European MetOp satellites.
 
As its main output, AAPP produces files of quality-controlled brightness temperature or radiance data for each instrument - either separately or mapped to a common field of view.  
 
AAPP is maintained by the EUMETSAT NWP SAF. The software is freely available by licence, and distributed by the UK Met Office. For further details, please see the AAPP web page.