ESA’s Operational Atmospheric Validation Strategy and Results
Thorsten Fehr(1), Ewa Kwiatkowska(2), Anne van Gijsel(3), Gottfried Kirchengast(4), Jean-Christopher Lambert(5), Pascal Lecomte(1), Hermann Oelhaf(6) and Giuseppe Ottavianelli(1)
(1) ESA, Via Galileo Galilei, 00044 Frascati, Italy
(2) ESA/ESTEC, Keplerlaan 1, 2201 AZ Noordwijk, Netherlands
(3) RIVM, Postbus 1, 3720 Bilthoven, Netherlands
(4) WegCenter/University of Graz, Leechgasse 25, 8010 Graz, Austria
(5) IASB-BIRA, Avenue Circulaire 3, 1180 Bruxelles, Belgium
(6) IMK-FZK/Universität Karlsruhe, , 76021 Karlsruhe, Germany
The geophysical validation by independent means provides a fundamental step in end-to-end on the overall data quality assessment. A comprehensive validation program is an inherent component of Operational Earth Observation (EO) missions. It needs to include both, validation using ground-based measurements as well as inter-comparisons with other space borne missions. They give information on instrument characterization and calibration as well as on the performance of its processing algorithms and most important the final geophysical products.
While ground observations enable estimation of product accuracies, the mission inter-comparisons are important to derive instrument in-orbit characterization not available from ground point collocations. The consistency of long and sustained validation time series and projects spanning independent and possibly not overlapping missions are needed to support climate research.
ESA is committed to perform the validation of its products, including atmospheric chemistry and physics data. Detailed results for ENVISAT’s GOMOS, MIPAS, SCIAMACHY and MERIS instruments will be presented. Several targeted activities are supported that cover the validation by ground based instruments, lidars, balloons, Radio Occultation and other satellite instrumentation, as well as the inter-calibration of lidar systems in the CEOS context. Long term strategies are being developed that shall allow the validation of independent missions and are covering types of geophysical measurements rather than individual instruments or missions.
In this context, CEOS/WGCV (Working Group on Calibration and Validation) is proposing a community derived process that establishes an international Quality Assurance Framework to facilitate harmonisation and interoperability of EO data, QA4EO.