Exploiting satellite measurements to explore uncertainties in UK bottom-up NO<sub><i>x</i></sub> emission estimates
<p>Nitrogen oxides (NO<span class="inline-formula"><sub><i>x</i></sub></span>, NO <span class="inline-formula">+</span> NO<span class="inline-formula"><sub>2</sub></span>) are potent air pollu...
| Main Authors: | , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2022-04-01
|
| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://acp.copernicus.org/articles/22/4323/2022/acp-22-4323-2022.pdf |
| Summary: | <p>Nitrogen oxides (NO<span class="inline-formula"><sub><i>x</i></sub></span>, NO <span class="inline-formula">+</span> NO<span class="inline-formula"><sub>2</sub></span>) are potent air pollutants which
directly impact on human health and which aid the formation of other
hazardous pollutants such as ozone (O<span class="inline-formula"><sub>3</sub></span>) and particulate matter. In this
study, we use satellite tropospheric column nitrogen dioxide (TCNO<span class="inline-formula"><sub>2</sub></span>)
data to evaluate the spatiotemporal variability and magnitude of the United
Kingdom (UK) bottom-up National Atmospheric Emissions Inventory (NAEI)
NO<span class="inline-formula"><sub><i>x</i></sub></span> emissions. Although emissions and TCNO<span class="inline-formula"><sub>2</sub></span> represent different
quantities, for UK city sources we find a spatial correlation of
<span class="inline-formula">∼0.5</span> between the NAEI NO<span class="inline-formula"><sub><i>x</i></sub></span> emissions and TCNO<span class="inline-formula"><sub>2</sub></span> from
the high-spatial-resolution TROPOspheric Monitoring Instrument (TROPOMI),
suggesting a good spatial distribution of emission sources in the inventory.
Between 2005 and 2015, the NAEI total UK NO<span class="inline-formula"><sub><i>x</i></sub></span> emissions and long-term
TCNO<span class="inline-formula"><sub>2</sub></span> record from the Ozone Monitoring Instrument (OMI), averaged over
England, show annually decreasing trends of 4.4 % and 2.2 %,
respectively. Top-down NO<span class="inline-formula"><sub><i>x</i></sub></span> emissions were derived in this study by
applying a simple mass balance approach to TROPOMI-observed downwind NO<span class="inline-formula"><sub>2</sub></span> plumes from city sources. Overall, these top-down estimates were
consistent with the NAEI, but for larger cities such as London and
Birmingham the inventory is significantly (<span class="inline-formula">>25</span> %) less than
the top-down emissions.</p> |
|---|---|
| ISSN: | 1680-7316 1680-7324 |