Digital Earth Emissivity Information System (DEEIS) - Instruments

AIRS Overview

The Atmospheric Infrared Sounder (AIRS) is a cross-track rotary scanning sensor with a ± 49.5 degrees (from nadir) ground coverage as well as views to cold space and onboard spectral and radiometric calibration sources per scan cycle. Its coverage is pole-to-pole and covers the globe two times per day (daytime and nighttime). The scan cycle has a period of 8/3 seconds during which ninety ground footprints are observed. Each 22.4 ms footprint contains a spectrum with all 2378 spectral samples. The IR spectral regions covered are 649 - 1136, 1216 - 1613, and 2164 - 2674 cm^-1. The IR spatial resolution of AIRS is 13.5 km at nadir from the 705.3 km orbit. The swath width is 1650 km. AIRS flies on NASA's Aqua satellite with a daytime equator crossing of roughly 13:30 local time on the ascending orbit pass.

Due to the high number of channels on AIRS, only the collection of 45 channels which make up the Surface Emissivity (Regression) channel set was chosen. These channels are displayed in the following table:

For this information and more regarding AIRS, please visit the AIRS website.