The ENVISAT Atmospheric Chemistry Instrument Validation Programme

Three atmospheric-chemistry sensors form part of the ENVISAT payload that has been placed into orbit in March 2002. This paper will discuss the validation aspects of these instruments. Although the main validation phase for the atmospheric instruments of ENVISAT will be completed soon, ongoing validation products will continue throughout the lifetime of the ENVISAT mission. The long-term validation phase will: Provide assurance of data quality and accuracy for applications such as climate change research Investigate the fully representative range of geophysical conditions Investigate the fully representative range of seasonal cycles Perform long term monitoring for instrumental drifts and other artefacts Validate new products.