AATSR Visible Channel Update Information

Studies of the long term stability of the AATSR visible channel calibration have shown that the drift does not follow a linear trend. A further correction is therefore needed to compensate for the deviation from the expected trend. Inspection of the data suggests that the calibration drift may be due to the gradual build up of a thin contaminant film on the optical surfaces of the visible calibration system, rather than by the gradual degradation of the exposed optics. A simple thin film model has been applied to the data that appears to confirm this hypothesis. A new drift correction based on this model is proposed, along with a guide to applying the new correction, in the AATSR Technical Note: Visible Channel Update, D. Smith, January 2006.

Keywords: ESA European Space Agency - Agence spatiale europeenne, observation de la terre, earth observation, satellite remote sensing, teledetection, geophysique, altimetrie, radar, chimique atmospherique, geophysics, altimetry, radar, atmospheric chemistry