GOME: scan-mirror degradation correction
J.M. Krijger(1), I Aben(1) and J. Landgraf(1)
(1) SRON, Sorbonnelaan 2, 3584 CC Utrecht, Netherlands
Degradation of optical components in space is a problem affecting many remote sensing instruments, due to the prolonged exposure to the conditions in orbit.
Degradation has been confirmed for GOME and will likely in the future similarly affect SCIAMACHY onboard ENVISAT, which makes understanding the degradation of GOME important. Over the 8 year life time of GOME, the measurements of the Earth radiances and the Sun irradiances were subject to different instrument degradation in the UV (e.g., scan mirror and PMDs). To quantify this degrading effect a comparison was made between the GOME reflectance spectra with forward simulations of GOME spectra based on adequate description of the atmosphere (ozone, temperature, and pressure profiles) obtained from co-located cloud-free independent ozone sonde measurements. For this purpose we used the polarization-sensitive measurement of the main channels of GOME, without correction for the polarization sensitivity of the instrument. The use of the polarization sensitive measurement excludes the degradation effect of the PMDs, and will isolate the scan mirror degradation.
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,