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In sommer of 2010 version 6 of the SCIAMACHY operational processor is planned to be delivered to ESA. The SCIAMACHY Quality Working Group recommended an implementation of the formaldehyde (HCHO) and glyoxal (CHOCHO) vertical columns into version 6 of the off-line processor. They are formed during the oxidation of volatile organic compounds (VOCs) emitted by plants, anthropogenic activities, and biomass burning. Due to a rather short lifetime of formaldehyde and glyoxal, their distribution maps, obtained by the SCIAMACHY, represent the emission fields of their precursors, VOCs. The descriptions of reference algorithm as well as all the cross-sections for formaldehyde and glyoxal retrievals were delivered to DLR by the Belgian Institute for Space Aeronomy (BIRA) (I. De Smedt, 2008) and by the IUP (F. Wittrock, 2006), respectively. Both retrievals are based on the DOAS technique. For the formaldehyde retrieval the spectral region of 328.5-346 nm was recommended. The absorption cross-sections of HCHO, O3, NO2, BrO, OClO, a Ring spectrum and a polynomial of the fifth order are included into the fitting procedure. Before conversion to the vertical columns, the slant columns have to be normalized by subtracting the slant columns measured over Pacific ocean, where the only source of formaldehyde is methane oxidation. After the conversion to the vertical columns, part of HCHO removed during the previous procedure has to be re-added to the final vertical column by adding of the mean vertical column calculated by the tropospheric chemistry model IMAGES (J.-F. Müller, 1995). This normalization is necessary to compensate for the offset introduced by the solar reference measurements and interferences by other absorbers. For the determination of glyoxal columns, the spectral region 435-457 nm was selected. In this case, the absorption cross-sections of CHOCHO, O3, NO2, H2O, O4, a Ring spectrum and a cubic polynomial are included in the fitting procedure. The normalization of the CHOCHO slant columns is performed in the same way as for formaldehyde.

Since the foundation of the SCIAMACHY Quality Working Group (SQWG) in a joint ESA-DLR-NIVR inter-agency effort in late 2006, the ESA operational Level 2 processor was significantly improved w.r.t. data quality and product range. During the last two years the product list was substantially enhanced by new (total columns of SO2, BrO, OClO, H2O, CO, Limb BrO profiles, Limb cloud flags) and improved products (total columns of O3, NO2, Absorbing Aerosol Index, Limb O3 profiles, Limb NO2 profiles). For example, important improvements were achieved in the O3 and NO2 profile calculation by implementing an upgraded retrieval scheme and using now Level 1b version 7.0 data with an improved pointing correction. Nadir products of total column O3 and Absorbing Aerosol Index were improved by applying a radiometric degradation correction (m-factors) in the Level 1 to 2 processing step.