GOME-2 - Metop's second-generation sensor for operational ozone monitoring

The Global Ozone Monitoring Experiment (GOME) was first launched on ESA's E RS-2 spacecraft on 20 April 1995. It is still operating extremely successfu lly, providing ozone and other valuable data even two years beyond its orig inal design lifetime. As the only European ozone-monitoring instrument with an actual flight heritage, GOME was therefore selected for the Metop serie s of satellites being jointly developed by ESA and Eumetsat for operational meteorology and climate monitoring. The phasing between the ERS-2 and Meto p development schedules has been such that many 'lessons learnt' could be i mplemented to improve the sensor's design, calibration and data processing. In addition, various spacecraft- and launcher-imposed modifications have m eant that eventually almost no subsystem has remained totally unchanged. Th e changes made to the sensor itself have also resulted in changes to the ca libration philosophy and to the processing of the scientific data. The new features of this second-generation sensor, known as GOME-2, are presented h ere.