Inter-comparison of MERIS and GOME atmospheric products: preliminary results.
Stefano Casadio(1) and Claus Zehner(2)
via Galileo Galilei, Frascati (RM),
(2) ESA/ESRIN, via Galileo Galilei, 00044, Austria
'MEdium Resolution Imaging Spectrometer' and 'Global Ozone Monitoring Experiment' instruments are flying onboard different platforms (ENVISAT and ERS-2 respectively). They are characterized by different space resolution, and are based upon different measurement principles. Nevertheless, it is demonstrated here that atmospheric parameters estimated from GOME spectral measurements can be used to inter-compare with MERS cloud and water vapour products with excellent precision. The advantage of using GOME cloud and water vapour data resides in the consolidated quality of these products, which have been validated extensively during the last decade. Moreover, both GOME and MERIS products provide global coverage.
This work focuses on MERIS ability to detect and characterize cloud coverage, and on the estimate of the columnar concentration of atmospheric water vapour, which are provided for very different observation scenarios. Preliminary results of MERIS-GOME comparison indicate an excellent agreement for water vapour estimates and cloud detection capacity, while the values of cloud and surface pressure provided by MERIS show offsets, although they are well correlated to those derived from GOME data.