IASI (Infrared Atmospheric Sounding Interferometer) has been designed for operational meteorological soundings with a very high level of accuracy (specifications on Temperature accuracy: 1K for 1 km and 10 % for humidity) being devoted to improved medium range weather forecast. It is also designed for atmospheric chemistry aiming at estimating and monitoring trace gases like ozone, methane or carbon monoxide on a global scale. The IASI system includes the 3 instruments, a data processing software integrated in the EPS ground segment and a technical expertise centre implemented in CNES Toulouse.
The measurement technique is based on passive IR remote sensing using an accurately calibrated Fourier Transform Spectrometer operating in the 3.7 - 15.5 µm spectral range and an associated infrared imager operating in the 10.3 - 12.5 µm spectral range. The optical configuration of the sounder is based on a Michelson interferometer. The integrated infrared imager allows the co registration of the IASI sounder with AVHRR imager on-board METOP.


Status: Operational
Satellite METOP
Launch Date: OCtober 2006
Type: Medium-resolution IR spectrometer
Measurements and Applications: Measures tropospheric moisture and temperature, column integrated contents of ozone, carbon monoxide, methane, dinitrogen oxide and other minor gases which affect tropospheric chemistry. Also measures sea surface and land temperature

Technical Characteristics

Resolution: 25 km
N. of Bands: 3

MWIR - TIR: 3.4 - 15.5 µm 

Swath: 2052 km




IASI CNES Web Page http://smsc.cnes.fr/IASI/