SCIAMACHY (Scanning Imaging Absorption Spectrometer for Atmospheric Cartography)is an atmospheric sensor aboard the European satellite ENVISAT. It was launched in March 2002 as a joint project of Germany, the Netherlands and Belgium. It measures atmospheric absorption in spectral bands from the ultraviolet to the near infrared (240 nm - 2380 nm), providing knowledge about the composition, dynamics and radiation balance of the atmosphere. Moreover, aerosols, cloud properties and surface reflection can be retrieved.
Objectives
SCIAMACHY was conceived to improve our global knowledge and understanding of a variety of issues of importance for the chemistry and physics of the atmosphere (troposphere, stratosphere and mesosphere) and potential changes resulting from either anthropogenic behavior or natural phenomena such as:
Stratospheric Ozone with focus on the Antarctic ozone hole and the mid-latitudes
Tropospheric pollution arising from industrial activity and biomass burning
Troposphere - stratosphere exchange
Special events such as volcanic eruptions, solar proton events, and related regional and global phenomena
Instrument
SCIAMACHY is an imaging spectrometer comprising a mirror system, a sun diffusor, a telescope, a spectrometer, a calibration unit and thermal and electronic subsystems. SCIAMACHY performs measurements in nadir, limb, and solar/lunar occultation geometry. From these measurements total column amounts and stratospheric profiles of a multitude of atmospheric constituents are retrieved on a global scale. The observations of trace gases are performed simultaneously and globally. Limitations occur on the night side of the orbit (eclipse mode), where the sun does not illuminate the atmosphere and, consequently, no reflected and backscattered solar radiation can be measured. In this mode, a sequence of eclipse observations (e.g. air glow, biomass burning) are achieved. Global coverage is obtained in three days.
A version with reduced capabilities, the Global Ozone Monitoring Experiment (GOME), has already been flying on ERS-2. As one of the atmospheric instruments on ENVISAT, SCIAMACHY data is complementing the information obtained with MIPAS, GOMOS and MERIS.