| Instrument |
Main purpose |
MERIS |
The MEdium Resolution Imaging Specrometer instrument measures radiation in 15 frequency bands that give information about ocean biology, marine water quality, vegetation on land, cloud and water
vapour. |
ASAR |
The Advanced Synthetic Aperture Radar provides all weather, day and night radar imaging. |
AATSR |
The Advanced Along Track Scanning Radiometer measures sea-surface temperature, a key parameter in determining the existence and/or extent of global warming. |
GOMOS |
The Global Ozone Monitoring by Occultation of Stars observes the concentration of ozone in the stratosphere. |
SCIAMACHY |
The SCanning Imaging Absorption SpectroMeter for Atmospheric CHartographY measures trace gases and aerosol concentrations in the atmosphere. |
MIPAS |
The Michelson Interferometer for Passive Atmospheric Sounding collects information about chemical and physical processes in the stratosphere, such as those that will affect ozone concentration in future. |
RA-2 |
The Radar Altimeter measures distance from satellite to Earth. So it can measure sea-surface height, an important measurement for monitoring El Niño, for example. |
MWR |
The Microwave radiometer allows corrections to be made to radar altimeter data. |
DORIS |
The Doppler Orbitography and Radiopositioning Integrated by Satellite gives the position of Envisat in its orbit to within a few centimetres.
This is crucial to understanding the measurements all the instruments make. |
LRR |
The Laser retro-reflector reflects pulsed laser to ground stations to help determine the satellite’s exact position in its orbit. |