| The Infrared Atmospheric Sounding Interferometer (IASI) consists of a Fourier Transform Spectrometer with an imaging system. It is based on a Michelson Interferometer and is designed to measure the infrared spectrum emitted by the earth.
IASI will provide improved infrared soundings of the temperature profiles in the troposphere and lower stratosphere, moisture profiles in the troposphere, as well as some of the chemical components playing a key role in the climate monitoring, global change and atmospheric chemistry.
The Centre National d'Études Spatiales (CNES) is leading the IASI programme in association with EUMETSAT. ALCATEL is the instrument Prime Contractor. The IASI will fly on MetOp 1, 2 and 3. | 
