THE ERS-2 SPACECRAFT AND ITS PAYLOAD

The ERS-2 satellite is essentially the same as ERS-1 except that it in cludes a number of enhancements and it is carrying a new payload instr ument to measure the chemical composition of the atmosphere, named the Global Ozone Monitoring Experiment (GOME). Other major instruments co mmon to ERS-1 and ERS-2 are the Active Microwave Instrument (AMI), the Radar Altimeter (RA), the Along-Track Scanning Radiometer (ATSR), the Microwave Radiometer (MWR) and the Precise Range and Range Rate Exper iment (PRARE). The AMI operates in three different modes devoted to ra dar imagery, and oceanic wind and wave measurements. The RA measures p recisely the altitude over ocean ice and land surfaces and also measur es oceanic wind and waves. The ATSR measures sea-surface temperatures and has been enhanced for ERS-2 by including visible channels for vege tation monitoring. The MWR and PRARE both support the RA mission by pr oviding information respectively on propagation delays of the radar si gnal and satellite positioning.