AIRS NRT Processing at NESDIS

The Atmospheric Infrared Sounder (AIRS) is the first high spectral resolution infrared sounder data to be routinely distributed to Numerical Weather Prediction (NWP) Centers in near real-time; generally within 3 hours from observation time. AIRS is a cooled grating array spectrometer. Spectral coverage 3.7 to 15.4 microns in 17 arrays with 2378 spectral channels. Spectral resolution n/Dn=1200, 15 km FOV from 725km orbit. AQUA was launched May 4, 2002.

The primary AIRS level 2 products include: temperature profile ( 1 K accuracy), moisture profile ( 15%), ozone ( 15 % (layers) and 3 % total). Accuracy is achieved in clear, cloud cleared, or above clouds. Algorithms developed by AIRS science team. Details can be obtained from the AIRS science team website

NESDIS AIRS NRT Processing system has been running soon after the launch of the instrument. Here is a brief description of the changes of the system since then. Daily products from NESDIS AIRS NRT system including Thinned Radiance files (HDF and BUFR):

a) center AIRS fov within every other AMSU-A fov, 324 AIRS channels + AMSU and HSB (11 MB per orbit)
b) 281 AIRS channels + AMSU and HSB (8 MB per orbit) using same thinning as a)
c) Same as a) but with all 3 x 3 AIRS fovs.
d) Full resolution AMSU and HSB
e) 200 principal component scores using same thinning as a)
* all include cloud indicator

Near Real Time SO2/Volcano Monitoring