Improving the polarization correction algorithm of GOME (Global Ozone Monitoring Experiment)

An interpretation is made of various algorithms that may be used to perform the polarization correction part of the calibration of the GOME-spectrometer on-board ERS-2. A description of the currently implemented algorithm, as deduced from the GOME extractor software is given. Errors are estimated by applying different correction algorithms to a sample of simulated observations. The currently implemented algorithm is shown to permit larger inaccuracies than necessary and small modifications are suggested that lead to substantial reduction in the errors, especially in the UV. Also, a new algorithm that deals more consistently with the variation of polarization with wavelength is presented. Our results are also relevant to SCIAMACHY, an instrument similar to but more versatile than GOME, to be launched on ENVISAT in 2000.