CCN08 - SERCO-IDEAS-QA4EO-RM/SUB28 - WP 2260 - IDEAS- QA4EO - Quality Assurance For Earth Observation - WP 2260 (Resp. F. BARNABA)

The project aims at advancing the work done in the framework of the QA4EO CCN5,  improving aerosol optical depth (AOD) and Ångström exponent (AE) retrievals based on a correction using synchronous NO2 data.  Development of this method is based on the fact that currently satellite climatological NO2 values are used for correcting the AOD retrievals for NO2 related optical depth. However, NO2 has high spatiotemporal variability and, hence, these values are rarely representative of the actual atmospheric conditions. Recently developed Pandonia Ground Network offers reliable, high measurement frequency ground-based data for NO2 column, alongside with current generation of satellites (S5P/TROPOMI) which provide a high NO2 spatial detail. These data will be used to evaluate the current uncertainty of AOD and AE retrievals and integrated procedures will be developed. Spatiotemporal AOD/NO2 characteristics using two (urban and suburban) neighbouring ground based stations (including AERONET, PGN and EUROSKYRAD related instrumentation) and satellite sensors will be analysed towards demonstrating the NO2 impact on AOD for such validation activities and ways to correct for it.