The Atmospheric Infrared Sounder (AIRS) Project at the NASA Jet Propulsion Laboratory (JPL) and the NASA Goddard Earth Sciences Data and Information Services Center (GES DISC) are pleased to announce the availability of Aqua AIRS Version 6 Level 3 (L3) data. The AIRS Version 6 processing code has a number of improvements in addition to the Level 2 (L2) improvements from which it is built.
Three of the significant changes for the Version 6 L3 data include:
- L3 support products which contain profile data at 100 vertical levels are now available.
- A TqJoint grid is available, which contains gridded data for a common set of temperature and water vapor observations.
- Water vapor and trace gas products are now reported both as layer and level quantities.
These and other noteworthy improvements are described in The AIRS/AMSU/HSB Version 6 Level 3 User Guide. To make best use of the L3 products, please refer to this user guide.
One of the most striking improvements in the Version 6 data is the increased yield in the L3, as shown in a comparison to the 500 hectoPascal (hPa) temperature from Version 5 (see the headline figure). This more complete coverage is brought about by improvements both in the L2 retrieval and in the gridding, with L2 measurements now distributed over the nine AIRS 13 kilometer (km) footprints, rather than the single Advanced Microwave Sounding Unit (AMSU) 45 km footprint.
Because of the significant improvements in the Version 6 products over Version 5 (and the failure of AMSU channel 5), Version 5 L3 processing ceased at the end of February 2013. The Version 5 data will continue to be available as a static data set in the GES DISC archive. Version 6 L3 processing is underway in the forward stream for both the AIRS and Microwave (AIRS+AMSU) and AIRS-only (Infrared-only) retrievals. Version 6 L3 processing of previous years of AIRS observations will follow the L2 processing, which is currently underway for the AIRS+AMSU data, and will be available in the GES DISC archive soon after the processing of the L2 files from which they are built.
The AIRS+AMSU+HSB (HSB stands for Humidity Sounder for Brazil) and AIRS-only processing of previous data will begin after the AIRS+AMSU processing is complete.
AIRS Version 6 L3 data will be available for analysis using the interactive data analysis tool Giovanni later in 2013.