SCIAMACHY (SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY) is a passive remote sensing spectrometer observing backscattered, reflected, transmitted or emitted radiation from the atmosphere and Earth's surface, in the wavelength range between 240 and 2380 nm. The instrument flies on board ENVISAT which was launched on 1 March 2002.

The primary scientific objective of SCIAMACHY is the global measurement of various trace gases in the troposphere and stratosphere, which are retrieved from the solar irradiance and Earth radiance spectra. The large wavelength is also ideally suited for the determination of aerosols and clouds. Validation of SCIAMACHY is essential to ensure the quality of these derived products.

One of the tasks of the SCIAMACHY Science Advisory Group (SSAG) is to give advice and assistance concerning the validation of SCIAMACHY. These activities are co-ordinated by the SCIAMACHY Validation and Interpretation Group (SCIAVALIG).