Significant advances in the AIRS Science Team Version-6 retrieval algorithm

The Goddard DISC generated products derived from AIRS/AMSU-A observations, starting from September 2002 when the AIRS instrument became stable, using the AIRS Science Team Version-5 retrieval algorithm. The AIRS Science Team Version-6 retrieval algorithm became operational at the Goddard DISC in late 2012. This paper describes some of the significant improvements in retrieval methodology contained in the Version-6 retrieval algorithm, compared to that used in Version-5. In particular, the Science Team made major changes with regard to the algorithms used to 1) derive surface skin temperature and surface spectral emissivity; 2) generate the initial state used to start the cloud clearing and retrieval procedures; and 3) determine Quality Control. This paper describes these advances found in the AIRS Version- 6 retrieval algorithm and demonstrates the improvements of some AIRS Version-6 products compared to those obtained using Version-5.