The ENVISAT Medium Resolution Imaging Spectrometer (MERIS)

The Medium Resolution Imaging Spectrometer (MERIS), developed by the European Space Agency (ESA) for the Envisat polar orbit mission, belongs to a new generation of ocean colour sensors which will yield a major improvement in the knowledge of such crucial processes as the ocean contribution to the carbon cycle. MERIS is an imaging spectrometer operated in a pushbroom mode which measures the radiance backscattered by the Earth in fifteen spectral bands located in the 390 nm-1040 nm part of the spectrum. The instrument covers a swath of 1150 km and offers a dual spatial resolution. The instrument is equipped with a high stability on-board calibration unit based on diffuser plates which are Sun illuminated.