Both the operational GOME lv2-products provided by DLR and scientific products derived from GOME spectra need to be validated by independent measurements over the lifetime of the GOME instrument. Ground-based zenith-sky UV-vis measurements from the NDSC and associated stations are one of the most important sources of validation measurements for GOME and later SCIAMACHY. The reason is, that the similarity in measurement principle ensures that most quantities are measured by both instruments, and that the measurement results can easily be compared. At the same solar zenith angle, the light path and the measuring volume for a nadir viewing space borne instrument is very similar to that of a ground-based zenith-sky viewing experiment. Good spatial and temporal coincidence assured, zenith-sky measurements can be used to quantify the errors of GOME measurements.
As an example, the plot shows vertical columns of NO2 derived from GOME measurements with the IUP Bremen DOAS algorithm as compared to the measurements from the zenith-sky instrument in Ny-Ålesund, 80°N.
you are interested in more information on GOME validation, please contact Annette
If you are interested in more information on GOME validation, please contact Annette Ladstätter-Weißenmayer.