GOME WAVELENGTH CALIBRATION USING SOLAR AND ATMOSPHERIC SPECTRA

C. Caspar and K. Chance

Spectral information in both GOME solar spectra and GOME radiance spectra
is used in conjunction with solar and atmospheric absorption reference
spectra to provide internal wavelength calibration for GOME. The algorithm
for determining wavelength calibration uses chi-square minimisation of a
merit function involving wavelength and the GOME slit function.  It is
quite robust, requires little GOME data in the processing (calibration
window regions with from 15 to 50 pixels), and provides absolute
wavelength calibration to a small fraction of a GOME pixel across the
entire GOME spectrum.  Preliminary work involving cross-correlation
between GOME radiance measurements and reference spectra, which may lead
to further improvements in absolute wavelength calibration, will also be
described.

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