Title: "High resolution modelling of atmospheric composition over Antwerp, Belgium".
by Catalina Poraicu
Abstract: Nitrogen dioxide (NO2) is an important pollutant gas that affects air quality and climate through its impacts on the formation of tropospheric ozone and secondary organic aerosols. Its primary source in the atmosphere is fossil fuel combustion, and therefore NO2 levels peak in regions with important anthropogenic activities. Satellite maps revealed the city of Antwerp in Flanders, Belgium, as one of the strongest NO2 hotspots worldwide. In this work, we investigate the NO2 distribution in Flanders, as recorded by ground-based concentration measurements, airborne data and remotely sensed columns, with the help of the high-resolution chemical-transport model Weather Research and Forecasting coupled with Chemistry (WRF-Chem) as a cross-comparison tool.
The simulated NO2 distributions are compared against (1) hourly measured concentration values from monitoring stations in Flanders, (2) vertical columns measured by an airborne hyperspectral imager Airborne Prism EXperiment (APEX), providing a 2-dimensional spatial mapping, on 27 and 29 June 2019, and (3) spaceborne NO2 columns obtained from the high-resolution Tropospheric Monitoring Instrument (TROPOMI) sensor aboard S5p. The consistency of the model biases across the three datasets will be discussed. The TROPOMI NO2 biases against APEX data were evaluated with the help of the model for TROPOMI v1.3.1 and the reprocessed product v2.3.1. The WRF-Chem model performance against TROPOMI and ground-based data will be discussed and characterized for a period of 15 days in June 2019. Finally, a mass balance approach was used to perform a crude inversion of NOx emissions, based on 15-day averaged TROPOMI columns. The emission correction is conducted only in regions with high columns and high sensitivity to emission changes, in order to minimize the errors due to wind transport. The improvements to emissions will be discussed for four key locations over the simulation area.
Where: Nicolet room at BIRA-IASB and Teams
When: Friday 21 April, 2PM
