Abstract
In this paper, we propose improved nitrogen dioxide (NO2) to nitrogen oxide (NOx) scaling factors for several data-driven methods that are used for the estimation of NOx power plant emissions from satellite observations of NO2. The scaling factors are deduced from high-resolution simulations of power plant plumes with the MicroHH large-eddy simulation model with a simplified chemistry and then applied to Sentinel-5 Precursor (S5P) TROPOspheric Monitoring Instrument (TROPOMI) NO2 satellite observations over the Matimba/Medupi power stations in South Africa. We show that due to the non-linear chemistry the optimal NO2 to NOx scaling factors depend on both the method employed and the specific segments of the plume from which emission estimate is derived. The scaling factors derived from the MicroHH simulations in this study are substantially (more than 50%) higher than the typical values used in the literature with actual NO2 observations. The results highlight the challenge in appropriately accounting for the conversion from NO2 to NOx when estimating point source emissions from satellite NO2 observations.
| Original language | English |
|---|---|
| Article number | 102171 |
| Number of pages | 11 |
| Journal | Atmospheric Pollution Research |
| Volume | 15 |
| Issue number | 7 |
| DOIs | |
| Publication status | Published - Jul 2024 |
Bibliographical note
Publisher Copyright:© 2024 Turkish National Committee for Air Pollution Research and Control
Funding
Most of the work performed in this paper was done in the framework of EU H2020 project CoCO2 (Grant No. 958927). The FMI team also acknowledge additional funding from the Research Council of Finland (Grant Numbers 353082, 357904, 359196, 359455 and 331829). The Copernicus Sentinel-5P/TROPOMI data used in this work are provided as part of the Sentinel-5P Product Algorithm Laboratory (S5P-PAL).
| Funders | Funder number |
|---|---|
| Research Council of Finland | 353082, 359455, 331829, 357904, 359196 |
| Horizon 2020 Framework Programme | 958927 |
Keywords
- Emission estimation
- MicroHH
- Nitrogen dioxide
- Nitrogen oxides
- Plume inversion
- Power station
- Satellite data
- Sentinel-5P
- TROPOMI