|Title||Top-down NOx emissions of european cities based on the downwind plume of modelled and space-borne tropospheric NO2 columns|
|Author(s)||Verstraeten, Willem W.; Boersma, Klaas Folkert; Douros, John; Williams, Jason E.; Eskes, Henk; Liu, Fei; Beirle, Steffen; Delcloo, Andy|
|Source||Sensors 18 (2018)9. - ISSN 1424-8220|
Meteorology and Air Quality
|Publication type||Refereed Article in a scientific journal|
|Keyword(s)||LOTOS-EUROS CTM - OMI data - Surface NO emissions - Tropospheric NO column|
Top-down estimates of surface NOX emissions were derived for 23 European cities based on the downwind plume decay of tropospheric nitrogen dioxide (NO2) columns from the LOTOS-EUROS (Long Term Ozone Simulation-European Ozone Simulation) chemistry transport model (CTM) and from Ozone Monitoring Instrument (OMI) satellite retrievals, averaged for the summertime period (April–September) during 2013. Here we show that the top-down NOX emissions derived from LOTOS-EUROS for European urban areas agree well with the bottom-up NOX emissions from the MACC-III inventory data (R2 = 0.88) driving the CTM demonstrating the potential of this method. OMI top-down NOX emissions over the 23 European cities are generally lower compared with the MACC-III emissions and their correlation is slightly lower (R2 = 0.79). The uncertainty on the derived NO2 lifetimes and NOX emissions are on average ~55% for OMI and ~63% for LOTOS-EUROS data. The downwind NO2 plume method applied on both LOTOS-EUROS and OMI tropospheric NO2 columns allows to estimate NOX emissions from urban areas, demonstrating that this is a useful method for real-time updates of urban NOX emissions with reasonable accuracy.