SCIAMACHY advanced data retrieval algorithm development.

The atmospheric chemistry instrument SCIAMACHY is a joint German-Dutch-Belgian contribution to the European Space Agency environmental satellite ENVISAT scheduled for launch in mid 2001. Instrument performance and calibration measurements recently carried out under thermal vacuum conditions have confirmed predicted performance. Algorithm development at SRON using the UV and visible part of the solar spectrum for ozone profile retrieval and the near infrared for carbon monoxide and methane retrieval has shown good progress. In particular, new avenues have been explored for the development of a fast operational algorithm for the retrieval of ozone profiles, including a new forward model based on perturbation theory that is faster than the current operational algorithm, coupled to a new inversion scheme with no use of a-priori ozone profile information. The near-infrared retrieval of CO and CH4 is expected to yield higher accuracy data products based on the optimization of retrieval using micro-windows. New and advanced SCIAMACHY data products will be piloted in the Netherlands SCIAMACHY Data Centre that complements the operational ENVISAT payload data segment.