The Status of the SCIAMACHY Line-of-Sight Knowledge

Kurzfassung

The line-of-sight pointing knowledge is one of the key parameters defining the quality of SCIAMACHY’s measurement data. Particularly for observation geometries with long light paths, i.e. limb and sun or moon occultations, a high LoS pointing knowledge accuracy ensures assigning correct tangent altitudes to retrieved atmospheric parameters. Over the entire SCIAMACHY mission a steady improvement of the pointing knowledge is achieved. Currently an overall high accuracy in the order of 2-3 mdeg is maintained. However the acquired data still show small effects which indicate systematic pointing uncertainties in the order of at most a few mdeg. We present these residual effects and discuss how they might be corrected for.